Pilates based core stability training in ambulant individuals with multiple sclerosis: protocol for a multi-centre randomised controlled trial.

Science.gov (United States)

Freeman, Jennifer; Fox, Esther; Gear, Margaret; Hough, Alan

2012-04-05

People with Multiple Sclerosis (MS) frequently experience balance and mobility impairments, including reduced trunk stability. Pilates-based core stability training, which is aimed at improving control of the body's stabilising muscles, is popular as a form of exercise with people with MS and therapists. A replicated single case series study facilitated by the Therapists in MS Group in the United Kingdom (UK) provides preliminary evidence that this approach can improve balance and mobility in ambulant people with MS; further evidence is needed to substantiate these findings to ensure that limited time, energy, finances and resources are used to best effect.This study builds upon the pilot work undertaken in the case series study by implementing a powered randomised controlled study, with the aims of: 1 Establishing the effectiveness of core stability training; 2 Comparing core stability training with standardised physiotherapy exercise; 3 Exploring underlying mechanisms of change associated with this intervention This is a multi-centre, double blind, block randomised, controlled trial. Eligible participants will be recruited from 4 UK centres. Participants will be randomly allocated to one of three groups: Pilates based core stability training, standardised physiotherapy exercise or contract-relax relaxation sessions (placebo control). All will receive face to face training sessions over a 12 week period; together with a 15 minute daily home programme. All will be assessed by a blinded assessor before training, at the end of the 12 week programme and at 4 week follow-up. The primary outcome measure is the 10 metre timed walk. Secondary outcome measures are the MS walking Scale (MSWS-12), the Functional Reach (forwards and lateral), a 10 point Numerical Rating Scale to determine "Difficulty in carrying a drink when walking", and the Activities-specific Balance Confidence (ABC) Scale. In addition, ultrasound imaging of the abdominal muscles will be performed before

Pilates based core stability training in ambulant individuals with multiple sclerosis: protocol for a multi-centre randomised controlled trial

Directory of Open Access Journals (Sweden)

Freeman Jennifer

2012-04-01

Full Text Available Abstract Background People with Multiple Sclerosis (MS frequently experience balance and mobility impairments, including reduced trunk stability. Pilates-based core stability training, which is aimed at improving control of the body's stabilising muscles, is popular as a form of exercise with people with MS and therapists. A replicated single case series study facilitated by the Therapists in MS Group in the United Kingdom (UK provides preliminary evidence that this approach can improve balance and mobility in ambulant people with MS; further evidence is needed to substantiate these findings to ensure that limited time, energy, finances and resources are used to best effect. This study builds upon the pilot work undertaken in the case series study by implementing a powered randomised controlled study, with the aims of: 1 Establishing the effectiveness of core stability training 2 Comparing core stability training with standardised physiotherapy exercise 3 Exploring underlying mechanisms of change associated with this intervention Methods This is a multi-centre, double blind, block randomised, controlled trial. Eligible participants will be recruited from 4 UK centres. Participants will be randomly allocated to one of three groups: Pilates based core stability training, standardised physiotherapy exercise or contract-relax relaxation sessions (placebo control. All will receive face to face training sessions over a 12 week period; together with a 15 minute daily home programme. All will be assessed by a blinded assessor before training, at the end of the 12 week programme and at 4 week follow-up. The primary outcome measure is the 10 metre timed walk. Secondary outcome measures are the MS walking Scale (MSWS-12, the Functional Reach (forwards and lateral, a 10 point Numerical Rating Scale to determine "Difficulty in carrying a drink when walking", and the Activities-specific Balance Confidence (ABC Scale. In addition, ultrasound imaging of the

Dosimetry audit for a multi-centre IMRT head and neck trial

International Nuclear Information System (INIS)

Clark, Catharine H.; Hansen, Vibeke Nordmark; Chantler, Hannah; Edwards, Craig; James, Hayley V.; Webster, Gareth; Miles, Elizabeth A.; Guerrero Urbano, M. Teresa; Bhide, Shree A.; Bidmead, A. Margaret; Nutting, Christoper M.

2009-01-01

Background and purpose: PARSPORT was a multi-centre randomised trial in the UK which compared Intensity-Modulated Radiotherapy (IMRT) and conventional radiotherapy (CRT) for patients with head and neck cancer. The dosimetry audit goals were to verify the plan delivery in participating centres, ascertain what tolerances were suitable for head and neck IMRT trials and develop an IMRT credentialing program. Materials and methods: Centres enrolling patients underwent rigorous quality assurance before joining the trial. Following this each centre was visited for a dosimetry audit, which consisted of treatment planning system tests, fluence verification films, combined field films and dose point measurements. Results: Mean dose point measurements were made at six centres. For the primary planning target volume (PTV) the differences with the planned values for the IMRT and CRT arms were -0.6% (1.8% to -2.4%) and 0.7% (2.0% to -0.9%), respectively. Ninety-four percent of the IMRT fluence films for individual fields passed gamma criterion of 3%/3 mm and 75% of the films for combined fields passed gamma criterion 4%/3 mm (no significant difference between dynamic delivery and step and shoot delivery). Conclusions: This audit suggests that a 3% tolerance could be applied for PTV point doses. For dose distributions tolerances of 3%/3 mm on individual fields and 4%/3 mm for combined fields are proposed for multi-centre head and neck IMRT trials.

A multi-centre randomised controlled trial of rehabilitation aimed at improving outdoor mobility for people after stroke: Study protocol for a randomised controlled trial

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Logan Pip A

2012-06-01

Full Text Available Abstract Background Up to 42% of all stroke patients do not get out of the house as much as they would like. This can impede a person’s quality of life. This study is testing the clinical effectiveness and cost effectiveness of a new outdoor mobility rehabilitation intervention by comparing it to usual care. Methods/design This is a multi-centre parallel group individually randomised, controlled trial. At least 506 participants will be recruited through 15 primary and secondary care settings and will be eligible if they are over 18 years of age, have had a stroke and wish to get out of the house more often. Participants are being randomly allocated to either the intervention group or the control group. Intervention group participants receive up to 12 rehabilitation outdoor mobility sessions over up to four months. The main component of the intervention is repeated practice of outdoor mobility with a therapist. Control group participants are receiving the usual intervention for outdoor mobility limitations: verbal advice and provision of leaflets provided over one session. Outcome measures are being collected using postal questionnaires, travel calendars and by independent assessors. The primary outcome measure is the Social Function domain of the SF36v2 quality of life assessment six months after recruitment. The secondary outcome measures include: functional ability, mobility, the number of journeys (monthly travel diaries, satisfaction with outdoor mobility, mood, health-related quality of life, resource use of health and social care. Carer mood information is also being collected. The mean Social Function score of the SF-36v2 will be compared between treatment arms using a multiple membership form of mixed effects multiple regression analysis adjusting for centre (as a fixed effect, age and baseline Social Function score as covariates and therapist as a multiple membership random effect. Regression coefficients and 95% confidence

Reporting non-adherence in cluster randomised trials: A systematic review.

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Agbla, Schadrac C; DiazOrdaz, Karla

2018-06-01

Treatment non-adherence in randomised trials refers to situations where some participants do not receive their allocated treatment as intended. For cluster randomised trials, where the unit of randomisation is a group of participants, non-adherence may occur at the cluster or individual level. When non-adherence occurs, randomisation no longer guarantees that the relationship between treatment receipt and outcome is unconfounded, and the power to detect the treatment effects in intention-to-treat analysis may be reduced. Thus, recording adherence and estimating the causal treatment effect adequately are of interest for clinical trials. To assess the extent of reporting of non-adherence issues in published cluster trials and to establish which methods are currently being used for addressing non-adherence, if any, and whether clustering is accounted for in these. We systematically reviewed 132 cluster trials published in English in 2011 previously identified through a search in PubMed. One-hundred and twenty three cluster trials were included in this systematic review. Non-adherence was reported in 56 cluster trials. Among these, 19 reported a treatment efficacy estimate: per protocol in 15 and as treated in 4. No study discussed the assumptions made by these methods, their plausibility or the sensitivity of the results to deviations from these assumptions. The year of publication of the cluster trials included in this review (2011) could be considered a limitation of this study; however, no new guidelines regarding the reporting and the handling of non-adherence for cluster trials have been published since. In addition, a single reviewer undertook the data extraction. To mitigate this, a second reviewer conducted a validation of the extraction process on 15 randomly selected reports. Agreement was satisfactory (93%). Despite the recommendations of the Consolidated Standards of Reporting Trials statement extension to cluster randomised trials, treatment adherence is

Design-corrected variation by centre in mortality reduction in the ERSPC randomised prostate cancer screening trial.

Science.gov (United States)

Hakama, Matti; Moss, Sue M; Stenman, Ulf-Hakan; Roobol, Monique J; Zappa, Marco; Carlsson, Sigrid; Randazzo, Marco; Nelen, Vera; Hugosson, Jonas

2017-06-01

Objectives To calculate design-corrected estimates of the effect of screening on prostate cancer mortality by centre in the European Randomised Study of Screening for Prostate Cancer (ERSPC). Setting The ERSPC has shown a 21% reduction in prostate cancer mortality in men invited to screening with follow-up truncated at 13 years. Centres either used pre-consent randomisation (effectiveness design) or post-consent randomisation (efficacy design). Methods In six centres (three effectiveness design, three efficacy design) with follow-up until the end of 2010, or maximum 13 years, the effect of screening was estimated as both effectiveness (mortality reduction in the target population) and efficacy (reduction in those actually screened). Results The overall crude prostate cancer mortality risk ratio in the intervention arm vs control arm for the six centres was 0.79 ranging from a 14% increase to a 38% reduction. The risk ratio was 0.85 in centres with effectiveness design and 0.73 in those with efficacy design. After correcting for design, overall efficacy was 27%, 24% in pre-consent and 29% in post-consent centres, ranging between a 12% increase and a 52% reduction. Conclusion The estimated overall effect of screening in attenders (efficacy) was a 27% reduction in prostate cancer mortality at 13 years' follow-up. The variation in efficacy between centres was greater than the range in risk ratio without correction for design. The centre-specific variation in the mortality reduction could not be accounted for by the randomisation method.

Randomised cluster trial to support informed parental decision-making for the MMR vaccine

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Bekker Hilary

2011-06-01

Full Text Available Abstract Background In the UK public concern about the safety of the combined measles, mumps and rubella [MMR] vaccine continues to impact on MMR coverage. Whilst the sharp decline in uptake has begun to level out, first and second dose uptake rates remain short of that required for population immunity. Furthermore, international research consistently shows that some parents lack confidence in making a decision about MMR vaccination for their children. Together, this work suggests that effective interventions are required to support parents to make informed decisions about MMR. This trial assessed the impact of a parent-centred, multi-component intervention (balanced information, group discussion, coaching exercise on informed parental decision-making for MMR. Methods This was a two arm, cluster randomised trial. One hundred and forty two UK parents of children eligible for MMR vaccination were recruited from six primary healthcare centres and six childcare organisations. The intervention arm received an MMR information leaflet and participated in the intervention (parent meeting. The control arm received the leaflet only. The primary outcome was decisional conflict. Secondary outcomes were actual and intended MMR choice, knowledge, attitude, concern and necessity beliefs about MMR and anxiety. Results Decisional conflict decreased for both arms to a level where an 'effective' MMR decision could be made one-week (effect estimate = -0.54, p Conclusions Whilst both the leaflet and the parent meeting reduced parents' decisional conflict, the parent meeting appeared to enable parents to act upon their decision leading to vaccination uptake.

The cost-effectiveness of a patient centred pressure ulcer prevention care bundle: Findings from the INTACT cluster randomised trial.

Science.gov (United States)

Whitty, Jennifer A; McInnes, Elizabeth; Bucknall, Tracey; Webster, Joan; Gillespie, Brigid M; Banks, Merrilyn; Thalib, Lukman; Wallis, Marianne; Cumsille, Jose; Roberts, Shelley; Chaboyer, Wendy

2017-10-01

Pressure ulcers are serious, avoidable, costly and common adverse outcomes of healthcare. To evaluate the cost-effectiveness of a patient-centred pressure ulcer prevention care bundle compared to standard care. Cost-effectiveness and cost-benefit analyses of pressure ulcer prevention performed from the health system perspective using data collected alongside a cluster-randomised trial. Eight tertiary hospitals in Australia. Adult patients receiving either a patient-centred pressure ulcer prevention care bundle (n=799) or standard care (n=799). Direct costs related to the intervention and preventative strategies were collected from trial data and supplemented by micro-costing data on patient turning and skin care from a 4-week substudy (n=317). The time horizon for the economic evaluation matched the trial duration, with the endpoint being diagnosis of a new pressure ulcer, hospital discharge/transfer or 28days; whichever occurred first. For the cost-effectiveness analysis, the primary outcome was the incremental costs of prevention per additional hospital acquired pressure ulcer case avoided, estimated using a two-stage cluster-adjusted non-parametric bootstrap method. The cost-benefit analysis estimated net monetary benefit, which considered both the costs of prevention and any difference in length of stay. All costs are reported in AU$(2015). The care bundle cost AU$144.91 (95%CI: $74.96 to $246.08) more per patient than standard care. The largest contributors to cost were clinical nurse time for repositioning and skin inspection. In the cost-effectiveness analysis, the care bundle was estimated to cost an additional $3296 (95%CI: dominant to $144,525) per pressure ulcer avoided. This estimate is highly uncertain. Length of stay was unexpectedly higher in the care bundle group. In a cost-benefit analysis which considered length of stay, the net monetary benefit for the care bundle was estimated to be -$2320 (95%CI -$3900, -$1175) per patient, suggesting the care

Protocol for the ProFHER (PROximal Fracture of the Humerus: Evaluation by Randomisation trial: a pragmatic multi-centre randomised controlled trial of surgical versus non-surgical treatment for proximal fracture of the humerus in adults

Directory of Open Access Journals (Sweden)

Maffulli Nicola

2009-11-01

Full Text Available Abstract Background Proximal humeral fractures, which occur mainly in older adults, account for approximately 4 to 5% of all fractures. Approximately 40% of these fractures are displaced fractures involving the surgical neck. Management of this group of fractures is often challenging and the outcome is frequently unsatisfactory. In particular it is not clear whether surgery gives better outcomes than non-surgical management. Currently there is much variation in the use of surgery and a lack of good quality evidence to inform this decision. Methods/Design We aim to undertake a pragmatic UK-based multi-centre randomised controlled trial evaluating the effectiveness and cost-effectiveness of surgical versus standard non-surgical treatment for adults with an acute closed displaced fracture of the proximal humerus with involvement of the surgical neck. The choice of surgical intervention is left to the surgeon, who must use techniques that they are fully experienced with. This will avoid 'learning curve' problems. We will promote good standards of non-surgical care, similarly insisting on care-provider competence, and emphasize the need for comparable provision of rehabilitation for both groups of patients. We aim to recruit 250 patients from a minimum of 18 NHS trauma centres throughout the UK. These patients will be followed-up for 2 years. The primary outcome is the Oxford Shoulder Score, which will be collected via questionnaires completed by the trial participants at 6, 12 and 24 months. This is a 12-item condition-specific questionnaire providing a total score based on the person's subjective assessment of pain and activities of daily living impairment. We will also collect data for other outcomes, including general health measures and complications, and for an economic evaluation. Additionally, we plan a systematic collection of reasons for non-inclusion of eligible patients who were not recruited into the trial, and their baseline

Ethical implications of excessive cluster sizes in cluster randomised trials.

Science.gov (United States)

Hemming, Karla; Taljaard, Monica; Forbes, Gordon; Eldridge, Sandra M; Weijer, Charles

2018-02-20

The cluster randomised trial (CRT) is commonly used in healthcare research. It is the gold-standard study design for evaluating healthcare policy interventions. A key characteristic of this design is that as more participants are included, in a fixed number of clusters, the increase in achievable power will level off. CRTs with cluster sizes that exceed the point of levelling-off will have excessive numbers of participants, even if they do not achieve nominal levels of power. Excessively large cluster sizes may have ethical implications due to exposing trial participants unnecessarily to the burdens of both participating in the trial and the potential risks of harm associated with the intervention. We explore these issues through the use of two case studies. Where data are routinely collected, available at minimum cost and the intervention poses low risk, the ethical implications of excessively large cluster sizes are likely to be low (case study 1). However, to maximise the social benefit of the study, identification of excessive cluster sizes can allow for prespecified and fully powered secondary analyses. In the second case study, while there is no burden through trial participation (because the outcome data are routinely collected and non-identifiable), the intervention might be considered to pose some indirect risk to patients and risks to the healthcare workers. In this case study it is therefore important that the inclusion of excessively large cluster sizes is justifiable on other grounds (perhaps to show sustainability). In any randomised controlled trial, including evaluations of health policy interventions, it is important to minimise the burdens and risks to participants. Funders, researchers and research ethics committees should be aware of the ethical issues of excessively large cluster sizes in cluster trials. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is

A cluster randomised controlled trial evaluating the effectiveness of eHealth-supported patient recruitment in primary care research: the TRANSFoRm study protocol.

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Mastellos, Nikolaos; Andreasson, Anna; Huckvale, Kit; Larsen, Mark; Curcin, Vasa; Car, Josip; Agreus, Lars; Delaney, Brendan

2015-02-03

Opportunistic recruitment is a highly laborious and time-consuming process that is currently performed manually, increasing the workload of already busy practitioners and resulting in many studies failing to achieve their recruitment targets. The Translational Medicine and Patient Safety in Europe (TRANSFoRm) platform enables automated recruitment, data collection and follow-up of patients, potentially improving the efficiency, time and costs of clinical research. This study aims to assess the effectiveness of TRANSFoRm in improving patient recruitment and follow-up in primary care trials. This multi-centre, parallel-arm cluster randomised controlled trial will compare TRANSFoRm-supported with standard opportunistic recruitment. Participants will be general practitioners and patients with gastro-oesophageal reflux disease from 40 primary care centres in five European countries. Randomisation will take place at the care centre level. The intervention arm will use the TRANSFoRm tools for recruitment, baseline data collection and follow-up. The control arm will use web-based case report forms and paper self-completed questionnaires. The primary outcome will be the proportion of eligible patients successfully recruited at the end of the 16-week recruitment period. Secondary outcomes will include the proportion of recruited patients with complete baseline and follow-up data and the proportion of participants withdrawn or lost to follow-up. The study will also include an economic evaluation and measures of technology acceptance and user experience. The study should shed light on the use of eHealth to improve the effectiveness of recruitment and follow-up in primary care research and provide an evidence base for future eHealth-supported recruitment initiatives. Reporting of results is expected in October 2015. EudraCT: 2014-001314-25.

Involving older people in a multi-centre randomised trial of a complex intervention in pre-hospital emergency care: implementation of a collaborative model.

Science.gov (United States)

Koniotou, Marina; Evans, Bridie Angela; Chatters, Robin; Fothergill, Rachael; Garnsworthy, Christopher; Gaze, Sarah; Halter, Mary; Mason, Suzanne; Peconi, Julie; Porter, Alison; Siriwardena, A Niroshan; Toghill, Alun; Snooks, Helen

2015-07-10

Health services research is expected to involve service users as active partners in the research process, but few examples report how this has been achieved in practice in trials. We implemented a model to involve service users in a multi-centre randomised controlled trial in pre-hospital emergency care. We used the generic Standard Operating Procedure (SOP) from our Clinical Trials Unit (CTU) as the basis for creating a model to fit the context and population of the SAFER 2 trial. In our model, we planned to involve service users at all stages in the trial through decision-making forums at 3 levels: 1) strategic; 2) site (e.g. Wales; London; East Midlands); 3) local. We linked with charities and community groups to recruit people with experience of our study population. We collected notes of meetings alongside other documentary evidence such as attendance records and study documentation to track how we implemented our model. We involved service users at strategic, site and local level. We also added additional strategic level forums (Task and Finish Groups and Writing Days) where we included service users. Service user involvement varied in frequency and type across meetings, research stages and locations but stabilised and increased as the trial progressed. Involving service users in the SAFER 2 trial showed how it is feasible and achievable for patients, carers and potential patients sharing the demographic characteristics of our study population to collaborate in a multi-centre trial at the level which suited their health, location, skills and expertise. A standard model of involvement can be tailored by adopting a flexible approach to take account of the context and complexities of a multi-site trial. Current Controlled Trials ISRCTN60481756. Registered: 13 March 2009.

Effects of patient safety culture interventions on incident reporting in general practice : A cluster randomised trial a cluster randomised trial

NARCIS (Netherlands)

Verbakel, Natasha J.; Langelaan, Maaike; Verheij, Theo J M; Wagner, Cordula; Zwart, Dorien L M

2015-01-01

Background: A constructive safety culture is essential for the successful implementation of patient safety improvements. Aim: To assess the effect of two patient safety culture interventions on incident reporting as a proxy of safety culture. Design and setting: A three-arm cluster randomised trial

Neoadjuvant chemoradiotherapy plus surgery versus active surveillance for oesophageal cancer: a stepped-wedge cluster randomised trial.

Science.gov (United States)

Noordman, Bo Jan; Wijnhoven, Bas P L; Lagarde, Sjoerd M; Boonstra, Jurjen J; Coene, Peter Paul L O; Dekker, Jan Willem T; Doukas, Michael; van der Gaast, Ate; Heisterkamp, Joos; Kouwenhoven, Ewout A; Nieuwenhuijzen, Grard A P; Pierie, Jean-Pierre E N; Rosman, Camiel; van Sandick, Johanna W; van der Sangen, Maurice J C; Sosef, Meindert N; Spaander, Manon C W; Valkema, Roelf; van der Zaag, Edwin S; Steyerberg, Ewout W; van Lanschot, J Jan B

2018-02-06

Neoadjuvant chemoradiotherapy (nCRT) plus surgery is a standard treatment for locally advanced oesophageal cancer. With this treatment, 29% of patients have a pathologically complete response in the resection specimen. This provides the rationale for investigating an active surveillance approach. The aim of this study is to assess the (cost-)effectiveness of active surveillance vs. standard oesophagectomy after nCRT for oesophageal cancer. This is a phase-III multi-centre, stepped-wedge cluster randomised controlled trial. A total of 300 patients with clinically complete response (cCR, i.e. no local or disseminated disease proven by histology) after nCRT will be randomised to show non-inferiority of active surveillance to standard oesophagectomy (non-inferiority margin 15%, intra-correlation coefficient 0.02, power 80%, 2-sided α 0.05, 12% drop-out). Patients will undergo a first clinical response evaluation (CRE-I) 4-6 weeks after nCRT, consisting of endoscopy with bite-on-bite biopsies of the primary tumour site and other suspected lesions. Clinically complete responders will undergo a second CRE (CRE-II), 6-8 weeks after CRE-I. CRE-II will include 18F-FDG-PET-CT, followed by endoscopy with bite-on-bite biopsies and ultra-endosonography plus fine needle aspiration of suspected lymph nodes and/or PET- positive lesions. Patients with cCR at CRE-II will be assigned to oesophagectomy (first phase) or active surveillance (second phase of the study). The duration of the first phase is determined randomly over the 12 centres, i.e., stepped-wedge cluster design. Patients in the active surveillance arm will undergo diagnostic evaluations similar to CRE-II at 6/9/12/16/20/24/30/36/48 and 60 months after nCRT. In this arm, oesophagectomy will be offered only to patients in whom locoregional regrowth is highly suspected or proven, without distant dissemination. The main study parameter is overall survival; secondary endpoints include percentage of patients who do not

Building a Multi-centre Clinical Research Facilitation Network: The ARC Experience

Directory of Open Access Journals (Sweden)

Ian Nicholson

2017-06-01

interest from general practitioner members but as yet no studies of general practice procedures have been forthcoming.Discussion: Vets want to be involved with clinical research. ARC has had early successes and will continue to grow - though more work is needed to encourage general practitioner members. Multi-centre research allows more cases to be recruited more quickly, adding weight to studies and shortening the period of data-gathering. These initial retrospective studies have generated a committed core of individuals seeking to create prospective studies together. An online tool is planned, to facilitate real-time case-recruitmentfor prospective multi-centre studies including randomised controlled trials. Anyone can join ARC, please email inicholsonvet@gmail.com.

Psychological and psychosocial functioning of children with burn scarring using cosmetic camouflage: a multi-centre prospective randomised controlled trial.

Science.gov (United States)

Maskell, Jessica; Newcombe, Peter; Martin, Graham; Kimble, Roy

2014-02-01

Burns leave patients with long-term physical scarring. Children with scarring are required to face challenges of reintegration into their community, including acceptance of an altered appearance and acceptance by others. This can be difficult given society's preoccupation with physical appearance. Limited research exists investigating validity of cosmetic camouflage as a psychosocial intervention for children with scarring. This study investigated whether using cosmetic camouflage (Microskin™) had a positive impact on health-related quality of life, self-concept and psychopathology for children and adolescents (8-17 years) with burn scarring. A prospective multi-centre randomised controlled trial was conducted across Australian and New Zealand paediatric hospitals. 63 participants (49 females, mean age 12.7 ± 2.1 years) were enrolled. Data points were baseline (Time 1) and at 8 weeks (Time 2) using reliable and valid psychometric measures. Findings indicate there were significant improvements in socialisation, school and appearance scales on the Paediatric Quality of Life Inventory and psychopathology scores particularly peer problems decreased. However self-concept remained stable from baseline throughout intervention use. Cosmetic camouflage appears to have a positive impact on quality of life particularly socialisation. Cosmetic camouflage is a valid tool to assist children with scarring to actively participate socially within their communities. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

Multi-Optimisation Consensus Clustering

Science.gov (United States)

Li, Jian; Swift, Stephen; Liu, Xiaohui

Ensemble Clustering has been developed to provide an alternative way of obtaining more stable and accurate clustering results. It aims to avoid the biases of individual clustering algorithms. However, it is still a challenge to develop an efficient and robust method for Ensemble Clustering. Based on an existing ensemble clustering method, Consensus Clustering (CC), this paper introduces an advanced Consensus Clustering algorithm called Multi-Optimisation Consensus Clustering (MOCC), which utilises an optimised Agreement Separation criterion and a Multi-Optimisation framework to improve the performance of CC. Fifteen different data sets are used for evaluating the performance of MOCC. The results reveal that MOCC can generate more accurate clustering results than the original CC algorithm.

The Scandinavian Propaten(®) trial - 1-year patency of PTFE vascular prostheses with heparin-bonded luminal surfaces compared to ordinary pure PTFE vascular prostheses - a randomised clinical controlled multi-centre trial.

Science.gov (United States)

Lindholt, J S; Gottschalksen, B; Johannesen, N; Dueholm, D; Ravn, H; Christensen, E D; Viddal, B; Flørenes, T; Pedersen, G; Rasmussen, M; Carstensen, M; Grøndal, N; Fasting, H

2011-05-01

To compare 1-year potencies' of heparin-bonded PTFE [(Hb-PTFE) (Propaten(®))] grafts with those of ordinary polytetraflouroethylene (PTFE) grafts in a blinded, randomised, clinically controlled, multi-centre study. Eleven Scandinavian centres enrolled 569 patients with chronic functional or critical lower limb ischaemia who were scheduled to undergo femoro-femoral bypass or femoro-poplitaeal bypass. The patients were randomised 1:1 stratified by centre. Patency was assessed by duplex ultrasound scanning. A total of 546 patients (96%) completed the study with adequate follow-up. Perioperative bleeding was, on average, 370 ml with PTFE grafts and 399 ml with Heparin-bonded PTFE grafts (p = 0.32). Overall, primary patency after 1 year was 86.4% for Hb-PTFE grafts and 79.9% for PTFE grafts (OR = 0.627, 95% CI: 0.398; 0.989, p = 0.043). Secondary patency was 88% in Hb-PTFE grafts and 81% in PTFE grafts (OR = 0.569 (0.353; 0.917, p = 0.020)). Subgroup analyses revealed that significant reduction in risk (50%) was observed when Hb-PTFE was used for femoro-poplitaeal bypass (OR = 0.515 (0.281; 0.944, p = 0.030)), and a significant reduction in risk (50%) was observed with Hb-PTFE in cases with critical ischaemia (OR = 0.490 (0.249; 0.962, p = 0.036)). The Hb-PTFE graft significantly reduced the overall risk of primary graft failure by 37%. Risk reduction was 50% in femoro-poplitaeal bypass cases and in cases with critical ischaemia. Copyright © 2011. Published by Elsevier Ltd.

Virtual patients design and its effect on clinical reasoning and student experience: a protocol for a randomised factorial multi-centre study

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Bateman James

2012-08-01

Full Text Available Abstract Background Virtual Patients (VPs are web-based representations of realistic clinical cases. They are proposed as being an optimal method for teaching clinical reasoning skills. International standards exist which define precisely what constitutes a VP. There are multiple design possibilities for VPs, however there is little formal evidence to support individual design features. The purpose of this trial is to explore the effect of two different potentially important design features on clinical reasoning skills and the student experience. These are the branching case pathways (present or absent and structured clinical reasoning feedback (present or absent. Methods/Design This is a multi-centre randomised 2x2 factorial design study evaluating two independent variables of VP design, branching (present or absent, and structured clinical reasoning feedback (present or absent.The study will be carried out in medical student volunteers in one year group from three university medical schools in the United Kingdom, Warwick, Keele and Birmingham. There are four core musculoskeletal topics. Each case can be designed in four different ways, equating to 16 VPs required for the research. Students will be randomised to four groups, completing the four VP topics in the same order, but with each group exposed to a different VP design sequentially. All students will be exposed to the four designs. Primary outcomes are performance for each case design in a standardized fifteen item clinical reasoning assessment, integrated into each VP, which is identical for each topic. Additionally a 15-item self-reported evaluation is completed for each VP, based on a widely used EViP tool. Student patterns of use of the VPs will be recorded. In one centre, formative clinical and examination performance will be recorded, along with a self reported pre and post-intervention reasoning score, the DTI. Our power calculations indicate a sample size of 112 is required for

Effects of a partially supervised conditioning programme in cystic fibrosis: an international multi-centre randomised controlled trial (ACTIVATE-CF): study protocol.

Science.gov (United States)

Hebestreit, Helge; Lands, Larry C; Alarie, Nancy; Schaeff, Jonathan; Karila, Chantal; Orenstein, David M; Urquhart, Don S; Hulzebos, Erik H J; Stein, Lothar; Schindler, Christian; Kriemler, Susi; Radtke, Thomas

2018-02-08

Physical activity (PA) and exercise have become an accepted and valued component of cystic fibrosis (CF) care. Regular PA and exercise can positively impact pulmonary function, improve physical fitness, and enhance health-related quality of life (HRQoL). However, motivating people to be more active is challenging. Supervised exercise programs are expensive and labour intensive, and adherence falls off significantly once supervision ends. Unsupervised or partially supervised programs are less costly and more flexible, but compliance can be more problematic. The primary objective of this study is to evaluate the effects of a partially supervised exercise intervention along with regular motivation on forced expiratory volume in 1 s (FEV 1 ) at 6 months in a large international group of CF patients. Secondary endpoints include patient reported HRQoL, as well as levels of anxiety and depression, and control of blood sugar. It is planned that a total of 292 patients with CF 12 years and older with a FEV 1  ≥ 35% predicted shall be randomised. Following baseline assessments (2 visits) patients are randomised into an intervention and a control group. Thereafter, they will be seen every 3 months for assessments in their centre for one year (4 follow-up visits). Along with individual counselling to increase vigorous PA by at least 3 h per week on each clinic visit, the intervention group documents daily PA and inactivity time and receives a step counter to record their progress within a web-based diary. They also receive monthly phone calls from the study staff during the first 6 months of the study. After 6 months, they continue with the step counter and web-based programme for a further 6 months. The control group receives standard care and keeps their PA level constant during the study period. Thereafter, they receive the intervention as well. This is the first large, international multi-centre study to investigate the effects of a PA intervention in CF with

12 A multi-centre randomised feasibility study evaluating the impact of a prognostic model for management of blunt chest wall trauma patients: stumbl trial.

Science.gov (United States)

Battle, Ceri; Hutchings, Hayley; Abbott, Zoe; O'neill, Claire; Groves, Sam; Watkins, Alan; Lecky, Fiona; Jones, Sally; Gagg, James; Body, Rick; Evans, Phillip

2017-12-01

A new prognostic model has been developed and externally validated, the aim of which is to assist in the management of the blunt chest wall trauma patient in the Emergency Department (ED). A definitive randomised controlled trial (impact trial), is required to assess the clinical and cost effectiveness of the new model, before it can be accepted in clinical practice. The purpose of this trial is to assess the feasibility and acceptability of such a definitive trial and inform its design. This feasibility trial is designed to test the methods of a multi-centre, cluster-randomised (stepped wedge) trial, with a substantial qualitative component. Four EDs in England and Wales will collect data for all blunt chest wall trauma patients over a five month period; in the initial period acting as the controls (normal care) and the second period, acting as the interventions (in which the new model will be used). Baseline measurements including completion of the SF-12v2 will be obtained on initial assessment in the ED. Patient outcome data will then be collected for any subsequent hospitalisations. Data collection will conclude with a six week follow-up completion of two surveys (SF-12v2 and Client Services Receipt Inventory).Analysis of outcomes will focus on feasibility, acceptability and trial processes and will include recruitment and retention rates, attendance at clinician training rates and use of model in the ED. Qualitative feedback will be obtained through clinician interviews and a research nurse focus group. An evaluation of the feasibility of health economics outcomes data will be completed. Wales Research Ethics Committee 6 granted approval for the trial in September 2016. Health Care Research Wales Research Permissions and the HRA have granted approval for the study. Patient recruitment commenced in February 2017. Planned dissemination is through publication in a peer-reviewed Emergency Medicine Journal, presentation at appropriate conferences and to

GestationaL Obesity Weight management: Implementation of National Guidelines (GLOWING): a pilot cluster randomised controlled trial of a guideline implementation intervention for the management of maternal obesity by midwives.

Science.gov (United States)

Heslehurst, Nicola; Rankin, Judith; McParlin, Catherine; Sniehotta, Falko F; Howel, Denise; Rice, Stephen; McColl, Elaine

2018-01-01

Weight management in pregnancy guidelines exist, although dissemination alone is an ineffective means of implementation. Midwives identify the need for support to overcome complex barriers to practice. An evaluation of an intervention to support midwives' guideline implementation would require a large-scale cluster randomised controlled trial. A pilot study is necessary to explore the feasibility of delivery and evaluation prior to a definitive trial. The GestationaL Obesity Weight management: Implementation of National Guidelines (GLOWING) trial aims to test whether it is feasible and acceptable to deliver a behaviour change intervention to support midwives' implementation of weight management guidelines. GLOWING is a multi-centre parallel group pilot cluster randomised controlled trial comparing the delivery of a behaviour change intervention for midwives versus usual practice. Four NHS Trusts (clusters) will be randomised to intervention and control arms, stratified by size of maternity services. The intervention uses social cognitive theory and consists of face-to-face midwifery training plus information resources for routine practice. The main outcomes are whether the intervention and trial procedures are feasible and acceptable to participants and the feasibility of recruitment and data collection for a definitive trial. Target recruitment involves all eligible midwives in the intervention arm recruited to receive the intervention, 30 midwives and pregnant women per arm for baseline and outcome questionnaire data collection and 20 midwives and women to provide qualitative data. All quantitative and qualitative analyses will be descriptive with the purpose of informing the development of the definitive trial. This pilot study has been developed to support community midwives' implementation of guidelines. Community midwives have been selected as they usually carry out the booking appointment which includes measuring and discussing maternal body mass index. A

A structured physical activity and fitness programme for older adults with intellectual disabilities: results of a cluster-randomised clinical trial.

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van Schijndel-Speet, M; Evenhuis, H M; van Wijck, R; van Montfort, K C A G M; Echteld, M A

2017-01-01

The physical activity level of older adults with intellectual disabilities (ID) is extremely low, and their fitness levels are far beneath accepted norms for older people with normal intelligence and comparable with frail older people. A physical activity programme, including an education programme, was developed for older adults with ID using behaviour change techniques. The programme aimed at improving or maintaining adequate levels of physical activity (primary outcome measure) and motor fitness, cardio respiratory fitness, morphologic and metabolic fitness, activities of daily living, cognitive functioning and depressive symptoms (secondary outcome measures). The programme's efficacy was evaluated in a cluster-randomised clinical trial among people aged 43 years and over with mild-moderate levels of ID. Five day-activity centres were randomised to the participation group. In these centres, 81 older adults participated in groups of 8 to 10 in the programme, three times a week during 8 months. The programme was executed by physical activity instructors and staff of day-activity centres. Five other day-activity centres were randomised to the control group; 70 older adults in these centres received care as usual. The generalised linear model with mixed effects was used to test the programme's effectiveness. Significant effects were found on physical activity, muscle strength, systolic and diastolic blood pressure, serum cholesterol level and cognitive functioning, in favour of the programme's participants. No significant improvements were found on balance, serum glucose, weight, waist circumference, walking speed, mobility, depression or instrumental activities of daily living. The physical activity and fitness programme has established small but significant effects in this sample, but generalising the findings to other settings is difficult due to significant participant dropout. Implementation of evidence-based physical activity programmes among older adults

Prophylactic antibiotic regimens in tumour surgery (PARITY) : a pilot multicentre randomised controlled trial

NARCIS (Netherlands)

Ghert, M.; Bhandari, M.; Deheshi, B.; Guyatt, G.; Holt, G.; O'Shea, T.; Randall, R. L.; Thabane, L.; Wunder, J.; Evaniew, N.; McKay, P.; Schneider, P.; Turcotte, R.; Madden, K.; Scott, T.; Sprague, S.; Simunovic, N.; Swinton, M.; Racano, A.; Heels-Ansdell, D.; Buckingham, L.; Rose, P.; Brigman, B.; Pullenayegum, E.; Ghert, M.; Evaniew, N.; Mckay, P.; Schneider, P.; Sobhi, G.; Chan, R.; Biljan, M.; Ferguson, P.; Wunder, J.; Griffin, A.; Mantas, I.; Wylie, A.; Han, A.; Grewal, G.; Turcotte, R.; Goulding, K.; Dandachli, F.; Matte, G.; Werier, J.; Abdelbary, H.; Paquin, K.; Cosgrove, H.; Dugal, A-M.; Jutte, P.; Ploegmakers, J. J. W.; Stevens, M.

2015-01-01

Objective Clinical studies of patients with bone sarcomas have been challenged by insufficient numbers at individual centres to draw valid conclusions. Our objective was to assess the feasibility of conducting a definitive multi-centre randomised controlled trial (RCT) to determine whether a

Protocol for the combined immunosuppression & radiotherapy in thyroid eye disease (CIRTED trial: A multi-centre, double-masked, factorial randomised controlled trial

Directory of Open Access Journals (Sweden)

Kingston Laura

2008-01-01

Full Text Available Abstract Background Medical management of thyroid eye disease remains controversial due to a paucity of high quality evidence on long-term treatment outcomes. Glucocorticoids are known to be effective initially but have significant side-effects with long-term use and recrudescence can occur on cessation. Current evidence is conflicting on the efficacy of radiotherapy and non-steroid systemic immunosuppression, and the majority of previous studies have been retrospective, uncontrolled, small or poorly designed. The Combined Immunosuppression and Radiotherapy in Thyroid Eye Disease (CIRTED trial was designed to investigate the efficacy of radiotherapy and azathioprine in combination with a standard course of oral prednisolone in patients with active thyroid eye disease. Methods/design Patients with active thyroid eye disease will be randomised to receive (i azathioprine or oral placebo and (ii radiotherapy or sham-radiotherapy in this multi-centre, factorial randomised control trial. The primary outcome is improvement in disease severity (assessed using a composite binary measure at 12 months and secondary end-points include quality of life scores and health economic measures. Discussion The CIRTED trial is the first study to evaluate the role of radiotherapy and azathioprine as part of a long-term, combination immunosuppressive treatment regime for Thyroid Eye Disease. It will provide evidence for the role of radiotherapy and prolonged immunosuppression in the management of this condition, as well as pilot data on their use in combination. We have paid particular attention in the trial design to establishing (a robust placebo controls and masking protocols which are effective and safe for both radiotherapy and the systemic administration of an antiproliferative drug; (b constructing effective inclusion and exclusion criteria to select for active disease; and (c selecting pragmatic outcome measures. Trial registration Current controlled trials

Missing continuous outcomes under covariate dependent missingness in cluster randomised trials.

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Hossain, Anower; Diaz-Ordaz, Karla; Bartlett, Jonathan W

2017-06-01

Attrition is a common occurrence in cluster randomised trials which leads to missing outcome data. Two approaches for analysing such trials are cluster-level analysis and individual-level analysis. This paper compares the performance of unadjusted cluster-level analysis, baseline covariate adjusted cluster-level analysis and linear mixed model analysis, under baseline covariate dependent missingness in continuous outcomes, in terms of bias, average estimated standard error and coverage probability. The methods of complete records analysis and multiple imputation are used to handle the missing outcome data. We considered four scenarios, with the missingness mechanism and baseline covariate effect on outcome either the same or different between intervention groups. We show that both unadjusted cluster-level analysis and baseline covariate adjusted cluster-level analysis give unbiased estimates of the intervention effect only if both intervention groups have the same missingness mechanisms and there is no interaction between baseline covariate and intervention group. Linear mixed model and multiple imputation give unbiased estimates under all four considered scenarios, provided that an interaction of intervention and baseline covariate is included in the model when appropriate. Cluster mean imputation has been proposed as a valid approach for handling missing outcomes in cluster randomised trials. We show that cluster mean imputation only gives unbiased estimates when missingness mechanism is the same between the intervention groups and there is no interaction between baseline covariate and intervention group. Multiple imputation shows overcoverage for small number of clusters in each intervention group.

REMCARE: Pragmatic Multi-Centre Randomised Trial of Reminiscence Groups for People with Dementia and their Family Carers: Effectiveness and Economic Analysis.

Directory of Open Access Journals (Sweden)

Robert T Woods

Full Text Available Joint reminiscence groups, involving people with dementia and family carers together, are popular, but the evidence-base is limited. This study aimed to assess the effectiveness and cost-effectiveness of joint reminiscence groups as compared to usual care.This multi-centre, pragmatic randomised controlled trial had two parallel arms: intervention group and usual-care control group. A restricted dynamic method of randomisation was used, with an overall allocation ratio of 1:1, restricted to ensure viable sized intervention groups. Assessments, blind to treatment allocation, were carried out at baseline, three months and ten months (primary end-point, usually in the person's home. Participants were recruited in eight centres, mainly through NHS Memory Clinics and NHS community mental health teams. Included participants were community resident people with mild to moderate dementia (DSM-IV, who had a relative or other care-giver in regular contact, to act as informant and willing and able to participate in intervention. 71% carers were spouses. 488 people with dementia (mean age 77.5were randomised: 268 intervention, 220 control; 350 dyads completed the study (206 intervention, 144 control. The intervention evaluated was joint reminiscence groups (with up to 12 dyads weekly for twelve weeks; monthly maintenance sessions for further seven months. Sessions followed a published treatment manual and were held in a variety of community settings. Two trained facilitators in each centre were supported by volunteers. Primary outcome measures were self-reported quality of life for the person with dementia (QoL-AD, psychological distress for the carer (General Health Questionnaire, GHQ-28. Secondary outcome measures included: autobiographical memory and activities of daily living for the person with dementia; carer stress for the carer; mood, relationship quality and service use and costs for both.The intention to treat analysis (ANCOVA identified no

Dental care resistance prevention and antibiotic prescribing modification-the cluster-randomised controlled DREAM trial.

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Löffler, Christin; Böhmer, Femke; Hornung, Anne; Lang, Hermann; Burmeister, Ulrike; Podbielski, Andreas; Wollny, Anja; Kundt, Günther; Altiner, Attila

2014-02-22

Bacterial resistance development is one of the most urgent problems in healthcare worldwide. In Europe, dentistry accounts for a comparatively high amount of antibiotic prescriptions. In light of increasing levels of bacterial resistance, this development is alarming. So far, very few interventional studies have been performed, and further research is urgently needed. By means of a complex educational intervention, the DREAM trial aims at optimising antibiotic prescribing behaviour of general dentists in Germany. This is a cluster-randomised controlled trial, where each cluster consists of one dental practice and all of its patients in a defined period. Participants are general dentists practicing in the German region of Mecklenburg-Western Pomerania. Randomisation takes place after baseline data collection (6 months) and will be stratified by the antibiotic prescribing rates of the participating dental practices. Dentists randomised into the intervention group will participate in a complex small group educational seminar that aims at: increasing knowledge on bacterial resistance, pharmacology, and prophylaxis of infectious endocarditis; increasing awareness of dentist-patient communication using video-taped vignettes of dentist-patient communication on antibiotic treatment; improving collaboration between general dentists, general practitioners, and practice-based cardiologists on the necessity of antibiotic prophylaxis; enhancing awareness of the dentists' own prescribing habits by providing antibiotic prescribing feedback; and increasing patient knowledge on antibiotic treatment by providing patient-centred information material on antibiotic prophylaxis of endocarditis. The dentists randomised into the control group will not receive any educational programme and provide care as usual. Primary outcome is the overall antibiotic prescribing rate measured at T1 (period of six months after intervention). In a subgroup of adult patients affected by odontogenic

Short video interventions to reduce mental health stigma: a multi-centre randomised controlled trial in nursing high schools.

Science.gov (United States)

Winkler, Petr; Janoušková, Miroslava; Kožený, Jiří; Pasz, Jiří; Mladá, Karolína; Weissová, Aneta; Tušková, Eva; Evans-Lacko, Sara

2017-12-01

We aimed to assess whether short video interventions could reduce stigma among nursing students. A multi-centre, randomised controlled trial was conducted. Participating schools were randomly selected and randomly assigned to receive: (1) an informational leaflet, (2) a short video intervention or (3) a seminar involving direct contact with a service user. The Community Attitudes towards Mental Illness (CAMI) and Reported and Intended Behaviour Scale (RIBS) were selected as primary outcome measures. SPANOVA models were built and Cohen's d calculated to assess the overall effects in each of the trial arms. Compared to the baseline, effect sizes immediately after the intervention were small in the flyer arm (CAMI: d = 0.25; RIBS: d = 0.07), medium in the seminar arm (CAMI: d = 0.61; RIBS: d = 0.58), and medium in the video arm (CAMI: d = 0.49 RIBS: d = 0.26; n = 237). Effect sizes at the follow-up were vanishing in the flyer arm (CAMI: d = 0.05; RIBS: d = 0.04), medium in the seminar arm (CAMI: d = 0.43; RIBS: d = 0.26; n = 254), and small in the video arm (CAMI: d = 0.22 RIBS: d = 0.21; n = 237). Seminar had the strongest and relatively stable effect on students' attitudes and intended behaviour, but the effect of short video interventions was also considerable and stable over time. Since short effective video interventions are relatively cheap, conveniently accessible and easy to disseminate globally, we recommend them for further research and development.

Restrictive versus liberal blood transfusion for acute upper gastrointestinal bleeding (TRIGGER): a pragmatic, open-label, cluster randomised feasibility trial.

Science.gov (United States)

Jairath, Vipul; Kahan, Brennan C; Gray, Alasdair; Doré, Caroline J; Mora, Ana; James, Martin W; Stanley, Adrian J; Everett, Simon M; Bailey, Adam A; Dallal, Helen; Greenaway, John; Le Jeune, Ivan; Darwent, Melanie; Church, Nicholas; Reckless, Ian; Hodge, Renate; Dyer, Claire; Meredith, Sarah; Llewelyn, Charlotte; Palmer, Kelvin R; Logan, Richard F; Travis, Simon P; Walsh, Timothy S; Murphy, Michael F

2015-07-11

Transfusion thresholds for acute upper gastrointestinal bleeding are controversial. So far, only three small, underpowered studies and one single-centre trial have been done. Findings from the single-centre trial showed reduced mortality with restrictive red blood cell (RBC) transfusion. We aimed to assess whether a multicentre, cluster randomised trial is a feasible method to substantiate or refute this finding. In this pragmatic, open-label, cluster randomised feasibility trial, done in six university hospitals in the UK, we enrolled all patients aged 18 years or older with new presentations of acute upper gastrointestinal bleeding, irrespective of comorbidity, except for exsanguinating haemorrhage. We randomly assigned hospitals (1:1) with a computer-generated randomisation sequence (random permuted block size of 6, without stratification or matching) to either a restrictive (transfusion when haemoglobin concentration fell below 80 g/L) or liberal (transfusion when haemoglobin concentration fell below 100 g/L) RBC transfusion policy. Neither patients nor investigators were masked to treatment allocation. Feasibility outcomes were recruitment rate, protocol adherence, haemoglobin concentration, RBC exposure, selection bias, and information to guide design and economic evaluation of the phase 3 trial. Main exploratory clinical outcomes were further bleeding and mortality at day 28. We did analyses on all enrolled patients for whom an outcome was available. This trial is registered, ISRCTN85757829 and NCT02105532. Between Sept 3, 2012, and March 1, 2013, we enrolled 936 patients across six hospitals (403 patients in three hospitals with a restrictive policy and 533 patients in three hospitals with a liberal policy). Recruitment rate was significantly higher for the liberal than for the restrictive policy (62% vs 55%; p=0·04). Despite some baseline imbalances, Rockall and Blatchford risk scores were identical between policies. Protocol adherence was 96% (SD 10) in

Multi-view clustering via multi-manifold regularized non-negative matrix factorization.

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Zong, Linlin; Zhang, Xianchao; Zhao, Long; Yu, Hong; Zhao, Qianli

2017-04-01

Non-negative matrix factorization based multi-view clustering algorithms have shown their competitiveness among different multi-view clustering algorithms. However, non-negative matrix factorization fails to preserve the locally geometrical structure of the data space. In this paper, we propose a multi-manifold regularized non-negative matrix factorization framework (MMNMF) which can preserve the locally geometrical structure of the manifolds for multi-view clustering. MMNMF incorporates consensus manifold and consensus coefficient matrix with multi-manifold regularization to preserve the locally geometrical structure of the multi-view data space. We use two methods to construct the consensus manifold and two methods to find the consensus coefficient matrix, which leads to four instances of the framework. Experimental results show that the proposed algorithms outperform existing non-negative matrix factorization based algorithms for multi-view clustering. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effectiveness of a Hospital-Based Work Support Intervention for Female Cancer Patients – A Multi-Centre Randomised Controlled Trial

Science.gov (United States)

Tamminga, Sietske J.; Verbeek, Jos H. A. M.; Bos, Monique M. E. M.; Fons, Guus; Kitzen, Jos J. E. M.; Plaisier, Peter W.; Frings-Dresen, Monique H. W.; de Boer, Angela G. E. M.

2013-01-01

Objective One key aspect of cancer survivorship is return-to-work. Unfortunately, many cancer survivors face problems upon their return-to-work. For that reason, we developed a hospital-based work support intervention aimed at enhancing return-to-work. We studied effectiveness of the intervention compared to usual care for female cancer patients in a multi-centre randomised controlled trial. Methods Breast and gynaecological cancer patients who were treated with curative intent and had paid work were randomised to the intervention group (n = 65) or control group (n = 68). The intervention involved patient education and support at the hospital and improvement of communication between treating and occupational physicians. In addition, we asked patient's occupational physician to organise a meeting with the patient and the supervisor to make a concrete gradual return-to-work plan. Outcomes at 12 months of follow-up included rate and time until return-to-work (full or partial), quality of life, work ability, work functioning, and lost productivity costs. Time until return-to-work was analyzed with Kaplan-Meier survival analysis. Results Return-to-work rates were 86% and 83% (p = 0.6) for the intervention group and control group when excluding 8 patients who died or with a life expectancy of months at follow-up. Median time from initial sick leave to partial return-to-work was 194 days (range 14–435) versus 192 days (range 82–465) (p = 0.90) with a hazard ratio of 1.03 (95% CI 0.64–1.6). Quality of life and work ability improved statistically over time but did not differ statistically between groups. Work functioning and costs did not differ statistically between groups. Conclusion The intervention was easily implemented into usual psycho-oncological care and showed high return-to-work rates. We failed to show any differences between groups on return-to-work outcomes and quality of life scores. Further research is needed to study which aspects of

Effects of a multi-faceted program to increase influenza vaccine uptake among health care workers in nursing homes : A cluster randomised controlled trial

NARCIS (Netherlands)

Looijmans-van den Akker, I.; van Delden, J.J.M.; Verheij, T.J.M.; van der Sande, M.A.B.; van Essen, G.A.; Riphagen-Dalhuisen, J.; Hulscher, M.E.; Hak, E.

2010-01-01

Despite the recommendation of the Dutch association of nursing home physicians (NVVA) to be immunized against influenza, vaccine uptake among HCWs in nursing homes remains unacceptably low. Therefore we conducted a cluster randomised controlled trial among 33 Dutch nursing homes to assess the

Comparison of illness representations dimensions and illness representation clusters in predicting outcomes in the first year following diagnosis of type 2 diabetes

DEFF Research Database (Denmark)

Skinner, T. C.; Carey, M. E.; Cradock, S.

2011-01-01

trial of a self-management education intervention for people with type 2 diabetes, completed measures of illness beliefs (coherence, timeline, impact, seriousness, personal responsibility) and depression along with HbA1c and body mass index (BMI), at baseline 4, 8 and 12 months. The results......This article explores the utility of cluster analysis of illness representations, in comparison to analysing each dimension of the individual's illness representation, to predict an individual's response to diagnosis of type 2 diabetes. Participants in a large multi-centre randomised controlled...

Unequal cluster sizes in stepped-wedge cluster randomised trials: a systematic review.

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Kristunas, Caroline; Morris, Tom; Gray, Laura

2017-11-15

To investigate the extent to which cluster sizes vary in stepped-wedge cluster randomised trials (SW-CRT) and whether any variability is accounted for during the sample size calculation and analysis of these trials. Any, not limited to healthcare settings. Any taking part in an SW-CRT published up to March 2016. The primary outcome is the variability in cluster sizes, measured by the coefficient of variation (CV) in cluster size. Secondary outcomes include the difference between the cluster sizes assumed during the sample size calculation and those observed during the trial, any reported variability in cluster sizes and whether the methods of sample size calculation and methods of analysis accounted for any variability in cluster sizes. Of the 101 included SW-CRTs, 48% mentioned that the included clusters were known to vary in size, yet only 13% of these accounted for this during the calculation of the sample size. However, 69% of the trials did use a method of analysis appropriate for when clusters vary in size. Full trial reports were available for 53 trials. The CV was calculated for 23 of these: the median CV was 0.41 (IQR: 0.22-0.52). Actual cluster sizes could be compared with those assumed during the sample size calculation for 14 (26%) of the trial reports; the cluster sizes were between 29% and 480% of that which had been assumed. Cluster sizes often vary in SW-CRTs. Reporting of SW-CRTs also remains suboptimal. The effect of unequal cluster sizes on the statistical power of SW-CRTs needs further exploration and methods appropriate to studies with unequal cluster sizes need to be employed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

WHEDA study: Effectiveness of occupational therapy at home for older people with dementia and their caregivers - the design of a pragmatic randomised controlled trial evaluating a Dutch programme in seven German centres

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Vernooij-Dassen Myrra

2009-10-01

Full Text Available Abstract Background A recent Dutch mono-centre randomised controlled trial has shown that occupational therapy improves daily functioning in dementia. The aim of this present study is to compare the effects of the Dutch community occupational therapy programme with a community occupational therapy consultation on daily functioning in older people with mild or moderate dementia and their primary caregivers in a German multi-centre context. Methods/Design A multi-centre single blind randomised controlled trial design is being used in seven health care centres (neurological, psychiatric and for older people in urban regions. Patients are 1:1 randomised to treatment or control group. Assessors are blind to group assignment and perform measurements on both groups at baseline, directly after intervention at 6 weeks and at 16, 26 and 52 weeks follow-up. A sample of 140 community dwelling older people (aged >65 years with mild or moderate dementia and their primary caregivers is planned. The experimental intervention consists of an evidence-based community occupational therapy programme including 10 sessions occupational therapy at home. The control intervention consists of one community occupational therapy consultation based on information material of the Alzheimer Society. Providers of both interventions are occupational therapists experienced in treatment of cognitively impaired older people and trained in both programmes. 'Community' indicates that occupational therapy intervention occurs in the person's own home. The primary outcome is patients' daily functioning assessed with the performance scale of the Interview for Deterioration in Daily Living Activities in Dementia and video tapes of daily activities rated by external raters blind to group assignment using the Perceive, Recall, Plan and Perform System of Task Analysis. Secondary outcomes are patients' and caregivers' quality of life, mood and satisfaction with treatment; the caregiver

The nutrition-based comprehensive intervention study on childhood obesity in China (NISCOC: a randomised cluster controlled trial

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Xu Guifa

2010-05-01

Full Text Available Abstract Background Childhood obesity and its related metabolic and psychological abnormalities are becoming serious health problems in China. Effective, feasible and practical interventions should be developed in order to prevent the childhood obesity and its related early onset of clinical cardiovascular diseases. The objective of this paper is to describe the design of a multi-centred random controlled school-based clinical intervention for childhood obesity in China. The secondary objective is to compare the cost-effectiveness of the comprehensive intervention strategy with two other interventions, one only focuses on nutrition education, the other only focuses on physical activity. Methods/Design The study is designed as a multi-centred randomised controlled trial, which included 6 centres located in Beijing, Shanghai, Chongqing, Shandong province, Heilongjiang province and Guangdong province. Both nutrition education (special developed carton style nutrition education handbook and physical activity intervention (Happy 10 program will be applied in all intervention schools of 5 cities except Beijing. In Beijing, nutrition education intervention will be applied in 3 schools and physical activity intervention among another 3 schools. A total of 9750 primary students (grade 1 to grade 5, aged 7-13 years will participate in baseline and intervention measurements, including weight, height, waist circumference, body composition (bioelectrical impendence device, physical fitness, 3 days dietary record, physical activity questionnaire, blood pressure, plasma glucose and plasma lipid profiles. Data concerning investments will be collected in our study, including costs in staff training, intervention materials, teachers and school input and supervising related expenditure. Discussion Present study is the first and biggest multi-center comprehensive childhood obesity intervention study in China. Should the study produce comprehensive results, the

Recruiting ENT and Audiology patients into pharmaceutical trials: evaluating the multi-centre experience in the UK and USA.

Science.gov (United States)

Sanchez, Victoria A; Hall, Deborah A; Millar, Bonnie; Escabi, Celia D; Sharman, Alice; Watson, Jeannette; Thasma, Sornaraja; Harris, Peter

2018-01-21

Recruiting into clinical trials on time and on target is a major challenge and yet often goes unreported. This study evaluated the adjustment to procedures, recruitment and screening methods in two multi-centre pharmaceutical randomised controlled trials (RCTs) for hearing-related problems in adults. Recruitment monitoring and subsequent adjustment of various study procedures (e.g. eligibility criteria, increasing recruiting sites and recruitment methods) are reported. Participants were recruited through eight overarching methods: trial registration, posters/flyers, print publications, Internet, social media, radio, databases and referrals. The efficiency of the recruitment was measured by determining the number of people: (1) eligible for screening as a percentage of those who underwent telephone pre-screening and (2) randomised as a percentage of those screened. A total of 584 participants completed the pre-screening steps, 491 screened and 169 participants were randomised. Both RCTs completed adjustments to the participant eligibility, added new study sites and additional recruitment methods. No single recruitment method was efficient enough to serve as the only route to enrolment. A diverse portfolio of methods, continuous monitoring, mitigation strategy and adequate resourcing were essential for achieving our recruitment goals.

Effect of obstetric team training on team performance and medical technical skills: a randomised controlled trial

NARCIS (Netherlands)

Fransen, A.F.; Ven, van de J.; Merién, A.E.R.; Wit-Zuurendonk, de L.D.; Houterman, S.; Mol, B.W.J.; Oei, S.G.

2012-01-01

Objective To determine whether obstetric team training in a medical simulation centre improves the team performance and utilisation of appropriate medical technical skills of healthcare professionals. Design Cluster randomised controlled trial. Setting The Netherlands. Sample The obstetric

Impact of person-centred care training and person-centred activities on quality of life, agitation, and antipsychotic use in people with dementia living in nursing homes: A cluster-randomised controlled trial.

Directory of Open Access Journals (Sweden)

Clive Ballard

2018-02-01

Full Text Available Agitation is a common, challenging symptom affecting large numbers of people with dementia and impacting on quality of life (QoL. There is an urgent need for evidence-based, cost-effective psychosocial interventions to improve these outcomes, particularly in the absence of safe, effective pharmacological therapies. This study aimed to evaluate the efficacy of a person-centred care and psychosocial intervention incorporating an antipsychotic review, WHELD, on QoL, agitation, and antipsychotic use in people with dementia living in nursing homes, and to determine its cost.This was a randomised controlled cluster trial conducted between 1 January 2013 and 30 September 2015 that compared the WHELD intervention with treatment as usual (TAU in people with dementia living in 69 UK nursing homes, using an intention to treat analysis. All nursing homes allocated to the intervention received staff training in person-centred care and social interaction and education regarding antipsychotic medications (antipsychotic review, followed by ongoing delivery through a care staff champion model. The primary outcome measure was QoL (DEMQOL-Proxy. Secondary outcomes were agitation (Cohen-Mansfield Agitation Inventory [CMAI], neuropsychiatric symptoms (Neuropsychiatric Inventory-Nursing Home Version [NPI-NH], antipsychotic use, global deterioration (Clinical Dementia Rating, mood (Cornell Scale for Depression in Dementia, unmet needs (Camberwell Assessment of Need for the Elderly, mortality, quality of interactions (Quality of Interactions Scale [QUIS], pain (Abbey Pain Scale, and cost. Costs were calculated using cost function figures compared with usual costs. In all, 847 people were randomised to WHELD or TAU, of whom 553 completed the 9-month randomised controlled trial. The intervention conferred a statistically significant improvement in QoL (DEMQOL-Proxy Z score 2.82, p = 0.0042; mean difference 2.54, SEM 0.88; 95% CI 0.81, 4.28; Cohen's D effect size 0

Initiating change locally in bullying and aggression through the school environment (INCLUSIVE) trial: update to cluster randomised controlled trial protocol.

Science.gov (United States)

Bonell, Chris; Mathiot, Anne; Allen, Elizabeth; Bevilacqua, Leonardo; Christie, Deborah; Elbourne, Diana; Fletcher, Adam; Grieve, Richard; Legood, Rosa; Scott, Stephen; Warren, Emily; Wiggins, Meg; Viner, Russell M

2017-05-25

Systematic reviews suggest that multi-component interventions are effective in reducing bullying victimisation and perpetration. We are undertaking a phase III randomised trial of the INCLUSIVE multi-component intervention. This trial aims to assess the effectiveness and cost-effectiveness of the INCLUSIVE intervention in reducing aggression and bullying victimisation in English secondary schools. This paper updates the original trial protocol published in 2014 (Trials 15:381, 2014) and presents the changes in the process evaluation protocol and the secondary outcome data collection. The methods are summarised as follows. cluster randomised trial. 40 state secondary schools. Outcomes assessed among the cohort of students at the end of year 7 (n = 6667) at baseline. INCLUSIVE is a multi-component school intervention including a social and emotional learning curriculum, changes to school environment (an action group comprising staff and students reviews local data on needs to review rules and policies and determine other local actions) and staff training in restorative practice. The intervention will be delivered by schools supported in the first two years by educational facilitators independent of the research team, with a third intervention year involving no external facilitation but all other elements. Comparator: normal practice. Primary: Two primary outcomes at student level assessed at baseline and at 36 months: 1. Aggressive behaviours in school: Edinburgh Study of Youth Transitions and Crime school misbehaviour subscale (ESYTC) 2. Bullying and victimisation: Gatehouse Bullying Scale (GBS) Secondary outcomes assessed at baseline, 24 and 36 months will include measures relating to the economic evaluation, psychosocial outcomes in students and staff and school-level truancy and exclusion rates. 20 schools per arm will provide 90% power to identify an effect size of 0.25 SD with a 5% significance level. Randomisation: eligible consenting schools were

Child Centred Approach to Climate Change and Health Adaptation through Schools in Bangladesh: A Cluster Randomised Intervention Trial.

Directory of Open Access Journals (Sweden)

Md Iqbal Kabir

Full Text Available Bangladesh is one of the most vulnerable countries to climate change. People are getting educated at different levels on how to deal with potential impacts. One such educational mode was the preparation of a school manual, for high school students on climate change and health protection endorsed by the National Curriculum and Textbook Board, which is based on a 2008 World Health Organization manual. The objective of this study was to test the effectiveness of the manual in increasing the knowledge level of the school children about climate change and health adaptation.This cluster randomized intervention trial involved 60 schools throughout Bangladesh, with 3293 secondary school students participating. School upazilas (sub-districts were randomised into intervention and control groups, and two schools from each upazila were randomly selected. All year seven students from both groups of schools sat for a pre-test of 30 short questions of binary response. A total of 1515 students from 30 intervention schools received the intervention through classroom training based on the school manual and 1778 students of the 30 control schools did not get the manual but a leaflet on climate change and health issues. Six months later, a post-intervention test of the same questionnaire used in the pre-test was performed at both intervention and control schools. The pre and post test scores were analysed along with the demographic data by using random effects model.None of the various school level and student level variables were significantly different between the control and intervention group. However, the intervention group had a 17.42% (95% CI: 14.45 to 20.38, P = <0.001 higher score in the post-test after adjusting for pre-test score and other covariates in a multi-level linear regression model.These results suggest that school-based intervention for climate change and health adaptation is effective for increasing the knowledge level of school children on

Understanding the cluster randomised crossover design: a graphical illustraton of the components of variation and a sample size tutorial.

Science.gov (United States)

Arnup, Sarah J; McKenzie, Joanne E; Hemming, Karla; Pilcher, David; Forbes, Andrew B

2017-08-15

In a cluster randomised crossover (CRXO) design, a sequence of interventions is assigned to a group, or 'cluster' of individuals. Each cluster receives each intervention in a separate period of time, forming 'cluster-periods'. Sample size calculations for CRXO trials need to account for both the cluster randomisation and crossover aspects of the design. Formulae are available for the two-period, two-intervention, cross-sectional CRXO design, however implementation of these formulae is known to be suboptimal. The aims of this tutorial are to illustrate the intuition behind the design; and provide guidance on performing sample size calculations. Graphical illustrations are used to describe the effect of the cluster randomisation and crossover aspects of the design on the correlation between individual responses in a CRXO trial. Sample size calculations for binary and continuous outcomes are illustrated using parameters estimated from the Australia and New Zealand Intensive Care Society - Adult Patient Database (ANZICS-APD) for patient mortality and length(s) of stay (LOS). The similarity between individual responses in a CRXO trial can be understood in terms of three components of variation: variation in cluster mean response; variation in the cluster-period mean response; and variation between individual responses within a cluster-period; or equivalently in terms of the correlation between individual responses in the same cluster-period (within-cluster within-period correlation, WPC), and between individual responses in the same cluster, but in different periods (within-cluster between-period correlation, BPC). The BPC lies between zero and the WPC. When the WPC and BPC are equal the precision gained by crossover aspect of the CRXO design equals the precision lost by cluster randomisation. When the BPC is zero there is no advantage in a CRXO over a parallel-group cluster randomised trial. Sample size calculations illustrate that small changes in the specification of

MultiComponent Exercise and theRApeutic lifeStyle (CERgAS) intervention to improve physical performance and maintain independent living among urban poor older people--a cluster randomised controlled trial.

Science.gov (United States)

Loh, Debbie Ann; Hairi, Noran Naqiah; Choo, Wan Yuen; Mohd Hairi, Farizah; Peramalah, Devi; Kandiben, Shathanapriya; Lee, Pek Ling; Gani, Norlissa; Madzlan, Mohamed Faris; Abd Hamid, Mohd Alif Idham; Akram, Zohaib; Chu, Ai Sean; Bulgiba, Awang; Cumming, Robert G

2015-02-11

The ability of older people to function independently is crucial as physical disability and functional limitation have profound impacts on health. Interventions that either delay the onset of frailty or attenuate its severity potentially have cascading benefits for older people, their families and society. This study aims to develop and evaluate the effectiveness of a multiComponent Exercise and theRApeutic lifeStyle (CERgAS) intervention program targeted at improving physical performance and maintaining independent living as compared to general health education among older people in an urban poor setting in Malaysia. This cluster randomised controlled trial will be a 6-week community-based intervention programme for older people aged 60 years and above from urban poor settings. A minimum of 164 eligible participants will be recruited from 8 clusters (low-cost public subsidised flats) and randomised to the intervention and control arm. This study will be underpinned by the Health Belief Model with an emphasis towards self-efficacy. The intervention will comprise multicomponent group exercise sessions, nutrition education, oral care education and on-going support and counselling. These will be complemented with a kit containing practical tips on exercise, nutrition and oral care after each session. Data will be collected over four time points; at baseline, immediately post-intervention, 3-months and 6-months follow-up. Findings from this trial will potentially provide valuable evidence to improve physical function and maintain independence among older people from low-resource settings. This will inform health policies and identify locally acceptable strategies to promote healthy aging, prevent and delay functional decline among older Malaysian adults. ISRCTN22749696.

Stepped-wedge cluster randomised controlled trials: a generic framework including parallel and multiple-level designs.

Science.gov (United States)

Hemming, Karla; Lilford, Richard; Girling, Alan J

2015-01-30

Stepped-wedge cluster randomised trials (SW-CRTs) are being used with increasing frequency in health service evaluation. Conventionally, these studies are cross-sectional in design with equally spaced steps, with an equal number of clusters randomised at each step and data collected at each and every step. Here we introduce several variations on this design and consider implications for power. One modification we consider is the incomplete cross-sectional SW-CRT, where the number of clusters varies at each step or where at some steps, for example, implementation or transition periods, data are not collected. We show that the parallel CRT with staggered but balanced randomisation can be considered a special case of the incomplete SW-CRT. As too can the parallel CRT with baseline measures. And we extend these designs to allow for multiple layers of clustering, for example, wards within a hospital. Building on results for complete designs, power and detectable difference are derived using a Wald test and obtaining the variance-covariance matrix of the treatment effect assuming a generalised linear mixed model. These variations are illustrated by several real examples. We recommend that whilst the impact of transition periods on power is likely to be small, where they are a feature of the design they should be incorporated. We also show examples in which the power of a SW-CRT increases as the intra-cluster correlation (ICC) increases and demonstrate that the impact of the ICC is likely to be smaller in a SW-CRT compared with a parallel CRT, especially where there are multiple levels of clustering. Finally, through this unified framework, the efficiency of the SW-CRT and the parallel CRT can be compared. © 2014 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Advance care planning - a multi-centre cluster randomised clinical trial

DEFF Research Database (Denmark)

Rietjens, Judith A C; Korfage, Ida J; Dunleavy, Lesley

2016-01-01

patients, relatives and professional caregivers about patients' values and care preferences. It raises awareness of the need to anticipate possible future deterioration of health. ACP has the potential to improve current and future healthcare decision-making, provide patients with a sense of control...... Choices program from the perspectives of patients, their Personal Representatives, healthcare providers and facilitators. DISCUSSION: Transferring the concept of ACP from care of the elderly to patients with advanced cancer, who on average are younger and retain their mental capacity for a larger part...

Advance care planning - a multi-centre cluster randomised clinical trial

DEFF Research Database (Denmark)

Rietjens, Judith A C; Korfage, Ida J; Dunleavy, Lesley

2016-01-01

patients, relatives and professional caregivers about patients' values and care preferences. It raises awareness of the need to anticipate possible future deterioration of health. ACP has the potential to improve current and future healthcare decision-making, provide patients with a sense of control......BACKGROUND: Awareness of preferences regarding medical care should be a central component of the care of patients with advanced cancer. Open communication can facilitate this but can occur in an ad hoc or variable manner. Advance care planning (ACP) is a formalized process of communication between...... Choices program from the perspectives of patients, their Personal Representatives, healthcare providers and facilitators. DISCUSSION: Transferring the concept of ACP from care of the elderly to patients with advanced cancer, who on average are younger and retain their mental capacity for a larger part...

Enhancing Recruitment Using Teleconference and Commitment Contract (ERUTECC): study protocol for a randomised, stepped-wedge cluster trial within the EFFECTS trial.

Science.gov (United States)

Lundström, Erik; Isaksson, Eva; Wester, Per; Laska, Ann-Charlotte; Näsman, Per

2018-01-08

Many randomised controlled trials (RCTs) fail to meet their recruitment goals in time. Trialists are advised to include study recruitment strategies within their trials. EFFECTS is a Swedish, academic-led RCT of fluoxetine for stroke recovery. The trial's primary objective is to investigate whether 20 mg fluoxetine daily compared with placebo for 6 months after an acute stroke improves the patient's functional outcome. The first patient was included on 20 October 2014 and, as of 31 August 2017, EFFECTS has included 810 of planned 1500 individuals. EFFECTS currently has 32 active centres. The primary objective of the ERUTECC (Enhancing Recruitment Using Teleconference and Commitment Contract) study is to investigate whether a structured teleconference re-visit with the study personnel at the centres, accompanied by a commitment contract, can enhance recruitment by 20% at 60 days post intervention, compared with 60 days pre-intervention, in an ongoing RCT. ERUTECC is a randomised, stepped-wedge cluster trial embedded in EFFECTS. The plan is to start ERUTECC with a running-in period of September 2017. The first intervention is due in October 2017, and the study will continue for 12 months. We are planning to intervene at all active centres in EFFECTS, except the five top recruiting centres (n = 27). The rationale for not intervening at the top recruiting centres is that we believe they have reached their full potential and the intervention would be too weak for them. The hypothesis of this study is that a structured teleconference re-visit with the study personnel at the centres, accompanied by a commitment contract, can enhance recruitment by 20% 60 days post intervention, compared to 60 days pre-intervention, in an ongoing RCT. EFFECTS is a large, pragmatic RCT of stroke in Sweden. Results from the embedded ERUTECC study could probably be generalised to high-income Western countries, and is relevant to trial management and could improve trial management in the

HLM in Cluster-Randomised Trials--Measuring Efficacy across Diverse Populations of Learners

Science.gov (United States)

Hegedus, Stephen; Tapper, John; Dalton, Sara; Sloane, Finbarr

2013-01-01

We describe the application of Hierarchical Linear Modelling (HLM) in a cluster-randomised study to examine learning algebraic concepts and procedures in an innovative, technology-rich environment in the US. HLM is applied to measure the impact of such treatment on learning and on contextual variables. We provide a detailed description of such…

Oxygen titration after resuscitation from out-of-hospital cardiac arrest: a multi-centre, randomised controlled pilot study (the EXACT pilot trial).

Science.gov (United States)

Bray, Janet E; Hein, Cindy; Smith, Karen; Stephenson, Michael; Grantham, Hugh; Finn, Judith; Stub, Dion; Cameron, Peter

2018-04-20

Recent studies suggest the administration of 100% oxygen to hyperoxic levels following return-of-spontaneous-circulation (ROSC) post-cardiac arrest may be harmful. However, the feasibility and safety of oxygen titration in the prehospital setting is unknown. We conducted a multi-centre, phase-2 study testing whether prehospital titration of oxygen results in an equivalent number of patients arriving at hospital with oxygen saturations SpO2 ≥ 94%. We enrolled unconscious adults with: sustained ROSC; initial shockable rhythm; an advanced airway; and an SpO2 ≥ 95%. Initially (Sept 2015-March 2016) patients were randomised 1:1 to either 2 litres/minute (L/min) oxygen (titrated) or >10 L/min oxygen (control) via a bag-valve reservoir. However, one site experienced a high number of desaturations (SpO2 titrated arm and this arm was changed (April 2016) to an initial reduction of oxygen to 4 L/min then, if tolerated, to 2 L/min, and the desaturation limit was decreased to titrated (n = 37: 2L/min = 20 and 2-4 L/min = 17) oxygen or control (n = 24). Patients allocated to titrated oxygen were more likely to desaturate compared to controls ((SpO2 titrated: 90% vs. control: 100%) and all patients had a SpO2 ≥ 90%. One patient (control) re-arrested. Survival to hospital discharge was similar. Oxygen titration post-ROSC is feasible in the prehospital environment, but incremental titration commencing at 4L/min oxygen flow may be needed to maintain an oxygen saturation >90% (NCT02499042). Copyright © 2018. Published by Elsevier B.V.

Reducing Medical Admissions into Hospital through Optimising Medicines (REMAIN HOME) Study: protocol for a stepped-wedge, cluster-randomised trial

Science.gov (United States)

Foot, Holly; Freeman, Christopher; Hemming, Karla; Scott, Ian; Coombes, Ian D; Williams, Ian D; Connelly, Luke; Whitty, Jennifer A; Sturman, Nancy; Kirsa, Sue; Nicholson, Caroline; Russell, Grant; Kirkpatrick, Carl; Cottrell, Neil

2017-01-01

Introduction A model of general practitioner (GP) and pharmacist collaboration in primary care may be an effective strategy to reduce medication-related problems and provide better support to patients after discharge. The aim of this study is to investigate whether a model of structured pharmacist and GP care reduces hospital readmissions in high-risk patients. Methods and analysis This protocol details a stepped-wedge, cluster-randomised trial that will recruit participants over 9 months with a 12-month follow-up. There will be 14 clusters each representing a different general practice medical centre. A total of 2240 participants will be recruited from hospital who attend an enrolled medical centre, take five or more long-term medicines or whose reason for admission was related to heart failure or chronic obstructive pulmonary disease. The intervention is a multifaceted service, involving a pharmacist integrated into a medical centre to assist patients after hospitalisation. Participants will meet with the practice pharmacist and their GP after discharge to review and reconcile their medicines and discuss changes made in hospital. The pharmacist will follow-up with the participant and liaise with other health professionals involved in the participant’s care. The control will be usual care, which usually involves a patient self-organising a visit to their GP after hospital discharge. The primary outcome is the rate of unplanned, all-cause hospital readmissions over 12 months, which will be analysed using a mixed effects Poisson regression model with a random effect for cluster and a fixed effect to account for any temporal trend. A cost analysis will be undertaken to compare the healthcare costs associated with the intervention to those of usual care. Ethics and dissemination The study has received ethical approval (HREC/16/QRBW/410). The study findings will be disseminated through peer-reviewed publications, conferences and reports to key stakeholders. Trial

Predictors of employment for people with severe mental illness : results of an international six-centre randomised controlled trial

NARCIS (Netherlands)

Catty, Jocelyn; Lissouba, Pascale; White, Sarah; Becker, Thomas; Drake, Robert E.; Fioritti, Angelo; Knapp, Martin; Lauber, Christoph; Roessler, Wulf; Tomov, Toma; Van Busschbach, Jooske; Wiersma, Durk; Burns, Tom; Rossler, W.

Background An international six-centre randomised controlled trial comparing individual placement and support (IPS) with usual vocational rehabilitation for people with serious mental illness found IPS to be more effective for all vocational outcomes. Aims To determine which patients with severe

A systematic review of cluster randomised trials in residential facilities for older people suggests how to improve quality.

Science.gov (United States)

Diaz-Ordaz, Karla; Froud, Robert; Sheehan, Bart; Eldridge, Sandra

2013-10-22

Previous reviews of cluster randomised trials have been critical of the quality of the trials reviewed, but none has explored determinants of the quality of these trials in a specific field over an extended period of time. Recent work suggests that correct conduct and reporting of these trials may require more than published guidelines. In this review, our aim was to assess the quality of cluster randomised trials conducted in residential facilities for older people, and to determine whether (1) statistician involvement in the trial and (2) strength of journal endorsement of the Consolidated Standards of Reporting Trials (CONSORT) statement influence quality. We systematically identified trials randomising residential facilities for older people, or parts thereof, without language restrictions, up to the end of 2010, using National Library of Medicine (Medline) via PubMed and hand-searching. We based quality assessment criteria largely on the extended CONSORT statement for cluster randomised trials. We assessed statistician involvement based on statistician co-authorship, and strength of journal endorsement of the CONSORT statement from journal websites. 73 trials met our inclusion criteria. Of these, 20 (27%) reported accounting for clustering in sample size calculations and 54 (74%) in the analyses. In 29 trials (40%), methods used to identify/recruit participants were judged by us to have potentially caused bias or reporting was unclear to reach a conclusion. Some elements of quality improved over time but this appeared not to be related to the publication of the extended CONSORT statement for these trials. Trials with statistician/epidemiologist co-authors were more likely to account for clustering in sample size calculations (unadjusted odds ratio 5.4, 95% confidence interval 1.1 to 26.0) and analyses (unadjusted OR 3.2, 1.2 to 8.5). Journal endorsement of the CONSORT statement was not associated with trial quality. Despite international attempts to improve

Multi-port versus single-port cholecystectomy: results of a multi-centre, randomised controlled trial (MUSIC trial).

Science.gov (United States)

Arezzo, Alberto; Passera, Roberto; Bullano, Alberto; Mintz, Yoav; Kedar, Asaf; Boni, Luigi; Cassinotti, Elisa; Rosati, Riccardo; Fumagalli Romario, Uberto; Sorrentino, Mario; Brizzolari, Marco; Di Lorenzo, Nicola; Gaspari, Achille Lucio; Andreone, Dario; De Stefani, Elena; Navarra, Giuseppe; Lazzara, Salvatore; Degiuli, Maurizio; Shishin, Kirill; Khatkov, Igor; Kazakov, Ivan; Schrittwieser, Rudolf; Carus, Thomas; Corradi, Alessio; Sitzman, Guenther; Lacy, Antonio; Uranues, Selman; Szold, Amir; Morino, Mario

2017-07-01

Single-port laparoscopic surgery as an alternative to conventional laparoscopic cholecystectomy for benign disease has not yet been accepted as a standard procedure. The aim of the multi-port versus single-port cholecystectomy trial was to compare morbidity rates after single-access (SPC) and standard laparoscopy (MPC). This non-inferiority phase 3 trial was conducted at 20 hospital surgical departments in six countries. At each centre, patients were randomly assigned to undergo either SPC or MPC. The primary outcome was overall morbidity within 60 days after surgery. Analysis was by intention to treat. The study was registered with ClinicalTrials.gov (NCT01104727). The study was conducted between April 2011 and May 2015. A total of 600 patients were randomly assigned to receive either SPC (n = 297) or MPC (n = 303) and were eligible for data analysis. Postsurgical complications within 60 days were recorded in 13 patients (4.7 %) in the SPC group and in 16 (6.1 %) in the MPC group (P = 0.468); however, single-access procedures took longer [70 min (range 25-265) vs. 55 min (range 22-185); P risk of incisional hernia following SPC do not appear to be justified. Patient satisfaction with aesthetic results was greater after SPC than after MPC.

Robust Inference with Multi-way Clustering

OpenAIRE

A. Colin Cameron; Jonah B. Gelbach; Douglas L. Miller; Doug Miller

2009-01-01

In this paper we propose a variance estimator for the OLS estimator as well as for nonlinear estimators such as logit, probit and GMM. This variance estimator enables cluster-robust inference when there is two-way or multi-way clustering that is non-nested. The variance estimator extends the standard cluster-robust variance estimator or sandwich estimator for one-way clustering (e.g. Liang and Zeger (1986), Arellano (1987)) and relies on similar relatively weak distributional assumptions. Our...

Efficacy and effectiveness of an rVSV-vectored vaccine in preventing Ebola virus disease: final results from the Guinea ring vaccination, open-label, cluster-randomised trial (Ebola Ça Suffit!).

Science.gov (United States)

Henao-Restrepo, Ana Maria; Camacho, Anton; Longini, Ira M; Watson, Conall H; Edmunds, W John; Egger, Matthias; Carroll, Miles W; Dean, Natalie E; Diatta, Ibrahima; Doumbia, Moussa; Draguez, Bertrand; Duraffour, Sophie; Enwere, Godwin; Grais, Rebecca; Gunther, Stephan; Gsell, Pierre-Stéphane; Hossmann, Stefanie; Watle, Sara Viksmoen; Kondé, Mandy Kader; Kéïta, Sakoba; Kone, Souleymane; Kuisma, Eewa; Levine, Myron M; Mandal, Sema; Mauget, Thomas; Norheim, Gunnstein; Riveros, Ximena; Soumah, Aboubacar; Trelle, Sven; Vicari, Andrea S; Røttingen, John-Arne; Kieny, Marie-Paule

2017-02-04

up for 84 days. 3149 (53·9%) of 5837 individuals reported at least one adverse event in the 14 days after vaccination; these were typically mild (87·5% of all 7211 adverse events). Headache (1832 [25·4%]), fatigue (1361 [18·9%]), and muscle pain (942 [13·1%]) were the most commonly reported adverse events in this period across all age groups. 80 serious adverse events were identified, of which two were judged to be related to vaccination (one febrile reaction and one anaphylaxis) and one possibly related (influenza-like illness); all three recovered without sequelae. The results add weight to the interim assessment that rVSV-ZEBOV offers substantial protection against Ebola virus disease, with no cases among vaccinated individuals from day 10 after vaccination in both randomised and non-randomised clusters. WHO, UK Wellcome Trust, the UK Government through the Department of International Development, Médecins Sans Frontières, Norwegian Ministry of Foreign Affairs (through the Research Council of Norway's GLOBVAC programme), and the Canadian Government (through the Public Health Agency of Canada, Canadian Institutes of Health Research, International Development Research Centre and Department of Foreign Affairs, Trade and Development). Copyright © 2017 World Health Organization. Published by Elsevier Ltd/Inc/BV. All rights reserved. Published by Elsevier Ltd.. All rights reserved.

Authorship issues in multi-centre clinical trials

DEFF Research Database (Denmark)

Rosenberg, Jacob; Burcharth, Jakob; Pommergaard, Hans-Christian

2015-01-01

Discussions about authorship often arise in multi-centre clinical trials. Such trials may involve up to hundreds of contributors of whom some will eventually co-author the final publication. It is, however, often impossible to involve all contributors in the manuscript process sufficiently for th...

INTroducing A Care bundle To prevent pressure injury (INTACT) in at-risk patients: A protocol for a cluster randomised trial.

Science.gov (United States)

Chaboyer, Wendy; Bucknall, Tracey; Webster, Joan; McInnes, Elizabeth; Banks, Merrilyn; Wallis, Marianne; Gillespie, Brigid M; Whitty, Jennifer A; Thalib, Lukman; Roberts, Shelley; Cullum, Nicky

2015-11-01

Pressure injuries are a significant clinical and economic issue, affecting both patients and the health care system. Many pressure injuries in hospitals are facility acquired, and are largely preventable. Despite growing evidence and directives for pressure injury prevention, implementation of preventative strategies is suboptimal, and pressure injuries remain a serious problem in hospitals. This study will test the effectiveness and cost-effectiveness of a patient-centred pressure injury prevention care bundle on the development of hospital acquired pressure injury in at-risk patients. This is a multi-site, parallel group cluster randomised trial. The hospital is the unit of randomisation. Adult medical and surgical patients admitted to the study wards of eight hospitals who are (a) deemed to be at risk of pressure injury (i.e. have reduced mobility), (b) expected to stay in hospital for ≥48h, (c) admitted to hospital in the past 36h; and (d) able to provide informed consent will be eligible to participate. Consenting patients will receive either the pressure injury prevention care bundle or standard care. The care bundle contains three main messages: (1) keep moving; (2) look after your skin; and (3) eat a healthy diet. Nurses will receive education about the intervention. Patients will exit the study upon development of a pressure injury, hospital discharge or 28 days, whichever comes first; transfer to another hospital or transfer to critical care and mechanically ventilated. The primary outcome is incidence of hospital acquired pressure injury. Secondary outcomes are pressure injury stage, patient participation in care and health care costs. A health economic sub-study and a process evaluation will be undertaken alongside the trial. Data will be analysed at the cluster (hospital) and patient level. Estimates of hospital acquired pressure injury incidence in each group, group differences and 95% confidence interval and p values will be reported. To our

The Happy Life Club™ study protocol: A cluster randomised controlled trial of a type 2 diabetes health coach intervention

Directory of Open Access Journals (Sweden)

Yang Hui

2011-02-01

Full Text Available Abstract Background The Happy Life Club™ is an intervention that utilises health coaches trained in behavioural change and motivational interviewing techniques to assist with the management of type 2 diabetes mellitus (T2DM in primary care settings in China. Health coaches will support participants to improve modifiable risk factors and adhere to effective self-management treatments associated with T2DM. Methods/Design A cluster randomised controlled trial involving 22 Community Health Centres (CHCs in Fengtai District of Beijing, China. CHCs will be randomised into a control or intervention group, facilitating recruitment of at least 1320 individual participants with T2DM into the study. Participants in the intervention group will receive a combination of both telephone and face-to-face health coaching over 18 months, in addition to usual care received by the control group. Health coaching will be performed by CHC doctors and nurses certified in coach-assisted chronic disease management. Outcomes will be assessed at baseline and again at 6, 12 and 18 months by means of a clinical health check and self-administered questionnaire. The primary outcome measure is HbA1c level. Secondary outcomes include metabolic, physiological and psychological variables. Discussion This cluster RCT has been developed to suit the Chinese health care system and will contribute to the evidence base for the management of patients with T2DM. With a strong focus on self-management and health coach support, the study has the potential to be adapted to other chronic diseases, as well as other regions of China. Trial Registration Current Controlled Trials ISRCTN01010526

Screening and brief interventions for hazardous alcohol use in accident and emergency departments: a randomised controlled trial protocol

Directory of Open Access Journals (Sweden)

Myles Judy

2009-07-01

service utilisation. Discussion This paper presents a protocol for a large multi-centre pragmatic factorial cluster randomised trial to evaluate the effectiveness and cost-effectiveness of screening and brief interventions for hazardous alcohol users attending emergency departments. Trial Registration ISRCTN 93681536

Prospective multi-centre randomised trial comparing induction of labour with a double-balloon catheter versus dinoprostone

DEFF Research Database (Denmark)

Løkkegaard, E; Lundstrøm, M; Kjær, Michael

2015-01-01

This randomised controlled study compared the efficacy of double-balloon catheter versus vaginal prostaglandin E2 (dinoprostone) for induction of labour. In total, 825 pregnant women with cephalic presentation and an unfavourable cervix undergoing induction for conventional indications were...... randomised to double-balloon or vaginal dinoprostone (3 mg) groups. There was a significantly higher failure rate for labour induction in the balloon group (relative risk: 1.25, 95% confidence interval [CI]: 1.02-1.49). Median induction time was 27.3 h in the balloon group and 29.8 h in the dinoprostone...

Authorship issues in multi-centre clinical trials

DEFF Research Database (Denmark)

Rosenberg, Jacob; Burcharth, Jakob; Pommergaard, Hans-Christian

2015-01-01

to qualify for authorship as defined by the International Committee of Medical Journal Editors. Therefore, rules for authorship in multi-centre trials are strongly recommended. We propose two contracts to prevent conflicts regarding authorship; both are freely available for use without pay but with reference...... to the original source....

Addressing the disconnect between public health science and personalised health care: the potential role of cluster analysis in combination with multi-criteria decision analysis

DEFF Research Database (Denmark)

Kaltoft, Mette Kjer; Dowie, Jack; Turner, Robin

2013-01-01

Background: Public health promotion and person-centred health care are being pursued simultaneously, with little attempt to resolve the conflict between them. One necessary step is to accept that health-care decisions involve multiple criteria and hence are preference sensitive. A second...... is to arrive at the necessary compromise between an individualised public policy (using each individual's preferences) and a deindividualised policy (using mean population preferences) in a more rigorous and transparent way. We show how cluster analysis can be combined with multi-criteria decision analysis...... (MCDA) to facilitate progression from variable-centred to person-centred public health, albeit at a subgroup level. Methods: Cluster analysis encompasses various techniques designed to detect patterns in the characteristics of individuals to establish the basis for policy decisions targeted at subgroups...

Re-estimating sample size in cluster randomized trials with active recruitment within clusters

NARCIS (Netherlands)

van Schie, Sander; Moerbeek, Mirjam

2014-01-01

Often only a limited number of clusters can be obtained in cluster randomised trials, although many potential participants can be recruited within each cluster. Thus, active recruitment is feasible within the clusters. To obtain an efficient sample size in a cluster randomised trial, the cluster

Intensification of Development of Mixed Transportation of Freight in Ukraine through Formation of the Network of Transportation and Logistic Centres and Transportation and Logistic Clusters

Directory of Open Access Journals (Sweden)

Karpenko Oksana O.

2013-11-01

Full Text Available Development of mixed transportation is a prospective direction of development of the transportation system of Ukraine. The article analyses the modern state of development of mixed transportation of freight in Ukraine. The most popular types of combined transportation (refers to multi-modal are container and contrailer trains, which are formed both in Ukraine (Viking and Yaroslav and in other countries, first of all, Belarus (Zubr. One of the reasons of underdevelopment of mixed transportation of freight in Ukraine is absence of a developed network of transportation and logistic centres. The article offers to form a network of transportation and logistic centres in Ukraine as a way of intensification of development of mixed transportations of freight, since they facilitate co-ordination of use of various types of transport and support integrated management of material flows. Transportation and logistic centres should become a start-up complex, around which transportation and logistic clusters would be gradually formed. Transportation and logistic clusters is a new efficient form of network organisation and management of transportation and logistic services and they also ensure growth of efficiency of use of the regional transportation and logistic potential of Ukraine. The article shows prospective supporting transportation and logistic centres and centres of formation of transportation and logistic clusters in the territory of Ukraine. Formation of efficient transportation and logistic system of Ukraine on the basis of a network of transportation and logistic clusters would facilitate entering of Ukraine into the world transportation environment and would allow acceleration of introduction of efficient logistic schemes of freight delivery, in particular, mixed transportation of freight.

Improved multi-objective clustering algorithm using particle swarm optimization.

Science.gov (United States)

Gong, Congcong; Chen, Haisong; He, Weixiong; Zhang, Zhanliang

2017-01-01

Multi-objective clustering has received widespread attention recently, as it can obtain more accurate and reasonable solution. In this paper, an improved multi-objective clustering framework using particle swarm optimization (IMCPSO) is proposed. Firstly, a novel particle representation for clustering problem is designed to help PSO search clustering solutions in continuous space. Secondly, the distribution of Pareto set is analyzed. The analysis results are applied to the leader selection strategy, and make algorithm avoid trapping in local optimum. Moreover, a clustering solution-improved method is proposed, which can increase the efficiency in searching clustering solution greatly. In the experiments, 28 datasets are used and nine state-of-the-art clustering algorithms are compared, the proposed method is superior to other approaches in the evaluation index ARI.

Conservative treatment of a mandibular condyle fracture: comparing intermaxillary fixation with screws or arch bar. A randomised clinical trial

NARCIS (Netherlands)

van den Bergh, B.; Blankestijn, J.; van der Ploeg, T.; Tuinzing, D.B.; Forouzanfar, T.

2015-01-01

Introduction A mandibular condyle fracture can be treated conservatively by intermaxillary fixation (IMF) or by open reposition and internal fixation (ORIF). Many IMF-modalities can be chosen, including IMF-screws (IMFS). This prospective multi-centre randomised clinical trial compared the use of

Conservative treatment of a mandibular condyle fracture: Comparing intermaxillary fixation with screws or arch bar. A randomised clinical trial

NARCIS (Netherlands)

van den Bergh, B.; Blankestijn, J.; van der Ploeg, T.; Tuinzing, D.B.; Forouzanfar, T.

2015-01-01

Introduction A mandibular condyle fracture can be treated conservatively by intermaxillary fixation (IMF) or by open reposition and internal fixation (ORIF). Many IMF-modalities can be chosen, including IMF-screws (IMFS). This prospective multi-centre randomised clinical trial compared the use of

Effects of a multi-level intervention on the pattern of physical activity among in-school adolescents in Oyo state Nigeria: a cluster randomised trial

Directory of Open Access Journals (Sweden)

Mojisola Morenike Oluwasanu

2017-10-01

Full Text Available Abstract Background Physical inactivity contributes to the global burden of non-communicable diseases. The pattern of physical activity in adulthood are often established during adolescence and sedentary behaviours in the early years could influence the development of diseases later in life. Studies on physical activity in Nigeria have focused largely on individual behaviours and the effects of school-based interventions have not been well investigated. The aim of the proposed study is to identify factors influencing; and evaluate the effects of a multi-level intervention on the physical activity behaviours of in-school adolescents in Oyo state, Nigeria. Methods The study will adopt a cluster randomised controlled trial design and schools will serve as the unit of randomisation. The sample size is 1000 in-school adolescents aged 10–19 years. The study will be guided by the socio-ecological model and theory of reasoned action and baseline data will be obtained through a mixed methods approach comprising a cross sectional survey to document the self-reported physical activity levels coupled with objectively measured physical activity levels using pedometers for a subset of the sample. Other measurements including weight, height, waist and hip circumferences, fitness level using the 20-m shuttle run test (20-mSRT and blood pressure will be obtained. The schools’ built environment and policy support for physical activity will be assessed using structured questionnaires coupled with key informant interviews and focus group discussions with the school authorities. Baseline findings will guide the design and implementation of a 12-week multi-level intervention. The primary outcome measures are self–reported and 7-day objectively measured physical activity. Other secondary outcome measures are body-mass-index for age, waist-to-hip ratio, cardioresiratory fitness and blood pressure. The association between behavioural factors and physical activity

Effects of unstratified and centre-stratified randomization in multi-centre clinical trials.

Science.gov (United States)

Anisimov, Vladimir V

2011-01-01

This paper deals with the analysis of randomization effects in multi-centre clinical trials. The two randomization schemes most often used in clinical trials are considered: unstratified and centre-stratified block-permuted randomization. The prediction of the number of patients randomized to different treatment arms in different regions during the recruitment period accounting for the stochastic nature of the recruitment and effects of multiple centres is investigated. A new analytic approach using a Poisson-gamma patient recruitment model (patients arrive at different centres according to Poisson processes with rates sampled from a gamma distributed population) and its further extensions is proposed. Closed-form expressions for corresponding distributions of the predicted number of the patients randomized in different regions are derived. In the case of two treatments, the properties of the total imbalance in the number of patients on treatment arms caused by using centre-stratified randomization are investigated and for a large number of centres a normal approximation of imbalance is proved. The impact of imbalance on the power of the study is considered. It is shown that the loss of statistical power is practically negligible and can be compensated by a minor increase in sample size. The influence of patient dropout is also investigated. The impact of randomization on predicted drug supply overage is discussed. Copyright © 2010 John Wiley & Sons, Ltd.

Does the effect of one-day simulation team training in obstetric emergencies decline within one year? A post-hoc analysis of a multicentre cluster randomised controlled trial.

Science.gov (United States)

van de Ven, J; Fransen, A F; Schuit, E; van Runnard Heimel, P J; Mol, B W; Oei, S G

2017-09-01

Does the effect of one-day simulation team training in obstetric emergencies decline within one year? A post-hoc analysis of a multicentre cluster randomised controlled trial. J van de Ven, AF Fransen, E Schuit, PJ van Runnard Heimel, BW Mol, SG Oei OBJECTIVE: To investigate whether the effect of a one-day simulation-based obstetric team training on patient outcome changes over time. Post-hoc analysis of a multicentre, open, randomised controlled trial that evaluated team training in obstetrics (TOSTI study).We studied women with a singleton pregnancy beyond 24 weeks of gestation in 24 obstetric units. Included obstetric units were randomised to either a one-day, multi-professional simulation-based team training focusing on crew resource management in a medical simulation centre (12 units) or to no team training (12 units). We assessed whether outcomes differed between both groups in each of the first four quarters following the team training and compared the effect of team training over quarters. Primary outcome was a composite outcome of low Apgar score, severe postpartum haemorrhage, trauma due to shoulder dystocia, eclampsia and hypoxic-ischemic encephalopathy. During a one year period after the team training the rate of obstetric complications, both on the composite level and the individual component level, did not differ between any of the quarters. For trauma due to shoulder dystocia team training led to a significant decrease in the first quarter (0.06% versus 0.26%, OR 0.19, 95% CI 0.03 to 0.98) but in the subsequent quarters no significant reductions were observed. Similar results were found for invasive treatment for severe postpartum haemorrhage where a significant increase was only seen in the first quarter (0.4% versus 0.03%, OR 19, 95% CI 2.5-147), and not thereafter. The beneficial effect of a one-day, simulation-based, multiprofessional, obstetric team training seems to decline after three months. If team training is further evaluated or

Beyond Low-Rank Representations: Orthogonal clustering basis reconstruction with optimized graph structure for multi-view spectral clustering.

Science.gov (United States)

Wang, Yang; Wu, Lin

2018-07-01

Low-Rank Representation (LRR) is arguably one of the most powerful paradigms for Multi-view spectral clustering, which elegantly encodes the multi-view local graph/manifold structures into an intrinsic low-rank self-expressive data similarity embedded in high-dimensional space, to yield a better graph partition than their single-view counterparts. In this paper we revisit it with a fundamentally different perspective by discovering LRR as essentially a latent clustered orthogonal projection based representation winged with an optimized local graph structure for spectral clustering; each column of the representation is fundamentally a cluster basis orthogonal to others to indicate its members, which intuitively projects the view-specific feature representation to be the one spanned by all orthogonal basis to characterize the cluster structures. Upon this finding, we propose our technique with the following: (1) We decompose LRR into latent clustered orthogonal representation via low-rank matrix factorization, to encode the more flexible cluster structures than LRR over primal data objects; (2) We convert the problem of LRR into that of simultaneously learning orthogonal clustered representation and optimized local graph structure for each view; (3) The learned orthogonal clustered representations and local graph structures enjoy the same magnitude for multi-view, so that the ideal multi-view consensus can be readily achieved. The experiments over multi-view datasets validate its superiority, especially over recent state-of-the-art LRR models. Copyright © 2018 Elsevier Ltd. All rights reserved.

A cluster randomised controlled trial of a manualised cognitive behavioural anger management intervention delivered by supervised lay therapists to people with intellectual disabilities.

Science.gov (United States)

Willner, P; Rose, J; Jahoda, A; Stenfert Kroese, B; Felce, D; MacMahon, P; Stimpson, A; Rose, N; Gillespie, D; Shead, J; Lammie, C; Woodgate, C; Townson, J K; Nuttall, J; Cohen, D; Hood, K

2013-05-01

Anger is a frequent problem for many people with intellectual disabilities, and is often expressed as verbal and/or physical aggression. Cognitive-behaviour therapy (CBT) is the treatment of choice for common mental health problems, but CBT has only recently been adapted for people with intellectual disabilities. Anger is the main psychological presentation in which controlled trials have been used to evaluate CBT interventions for people with intellectual disabilities but these do not include rigorous randomised studies. To evaluate (1) the impact of a staff-delivered manualised CBT anger management intervention on (a) reported anger among people with mild to moderate intellectual disabilities, and (b) anger coping skills, aggression, mental health, quality of life and costs of health and social care; (2) factors that influence outcome; and (3) the experience of service users, lay therapists and service managers. A cluster randomised controlled trial based on 30 day centres (15 intervention and 15 control). Intention-to-treat comparisons of outcomes used a two-level linear regression model to allow for clustering within centres with baseline outcome levels as a covariate. Comparison of cost data used non-parametric bootstrapping. Qualitative analysis used interpretative phenomenological analysis and thematic analysis. Recruited day centres had four-plus service users with problem anger who were prepared to participate, two-plus staff willing to be lay therapists, a supportive manager and facilities for group work, and no current anger interventions. A total of 212 service users with problem anger were recruited. Thirty-three were deemed ineligible (30 could not complete assessments and three withdrew before randomisation). Retention at follow-up was 81%, with 17 withdrawals in each arm. Two to four staff per centre were recruited as lay therapists. Eleven service users, nine lay therapists and eight managers were interviewed. The manualised intervention comprised

Improved multi-objective clustering algorithm using particle swarm optimization.

Directory of Open Access Journals (Sweden)

Congcong Gong

Full Text Available Multi-objective clustering has received widespread attention recently, as it can obtain more accurate and reasonable solution. In this paper, an improved multi-objective clustering framework using particle swarm optimization (IMCPSO is proposed. Firstly, a novel particle representation for clustering problem is designed to help PSO search clustering solutions in continuous space. Secondly, the distribution of Pareto set is analyzed. The analysis results are applied to the leader selection strategy, and make algorithm avoid trapping in local optimum. Moreover, a clustering solution-improved method is proposed, which can increase the efficiency in searching clustering solution greatly. In the experiments, 28 datasets are used and nine state-of-the-art clustering algorithms are compared, the proposed method is superior to other approaches in the evaluation index ARI.

A randomised, double-blind, multi-centre trial comparing vasopressin and adrenaline in patients with cardiac arrest presenting to or in the Emergency Department.

Science.gov (United States)

Ong, Marcus Eng Hock; Tiah, Ling; Leong, Benjamin Sieu-Hon; Tan, Elaine Ching Ching; Ong, Victor Yeok Kein; Tan, Elizabeth Ai Theng; Poh, Bee Yen; Pek, Pin Pin; Chen, Yuming

2012-08-01

To compare vasopressin and adrenaline in the treatment of patients with cardiac arrest presenting to or in the Emergency Department (ED). A randomised, double-blind, multi-centre, parallel-design clinical trial in four adult hospitals. Eligible cardiac arrest patients (confirmed by the absence of pulse, unresponsiveness and apnea) aged >16 (aged>21 for one hospital) were randomly assigned to intravenous adrenaline (1mg) or vasopressin (40 IU) at ED. Patients with traumatic cardiac arrest or contraindication for cardiopulmonary resuscitation (CPR) were excluded. Patients received additional open label doses of adrenaline as per current guidelines. Primary outcome was survival to hospital discharge (defined as participant discharged alive or survival to 30 days post-arrest). The study recruited 727 participants (adrenaline = 353; vasopressin = 374). Baseline characteristics of the two groups were comparable. Eight participants (2.3%) from adrenaline and 11 (2.9%) from vasopressin group survived to hospital discharge with no significant difference between groups (p = 0.27, RR = 1.72, 95% CI = 0.65-4.51). After adjustment for race, medical history, bystander CPR and prior adrenaline given, more participants survived to hospital admission with vasopressin (22.2%) than with adrenaline (16.7%) (p = 0.05, RR = 1.43, 95% CI = 1.02-2.04). Sub-group analysis suggested improved outcomes for vasopressin in participants with prolonged arrest times. Combination of vasopressin and adrenaline did not improve long term survival but seemed to improve survival to admission in patients with prolonged cardiac arrest. Further studies on the effect of vasopressin combined with therapeutic hypothermia on patients with prolonged cardiac arrest are needed. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

A randomised comparison of an everolimus-eluting coronary stent with a paclitaxel-eluting coronary stent:the SPIRIT II trial

NARCIS (Netherlands)

Serruys, Patrick W.; Ruygrok, Peter; Neuzner, Jörg; Piek, Jan J.; Seth, Ashok; Schofer, Joachim J.; Richardt, Gert; Wiemer, Marcus; Carrié, Didier; Thuesen, Leif; Boone, Els; Miquel-Herbert, Karine; Daemen, Joost

2006-01-01

Background: Everolimus has been successfully tested in humans using both an erodable and a durable polymer in small previous studies.Methods: This single blind multi-centre non-inferiority randomised (3:1) controlled trial evaluated the safety and performance of the XIENCE V Everolimus Eluting

The effects of a randomised multi-centre trial and international accreditation on availability and quality of clinical guidelines

DEFF Research Database (Denmark)

Juul, Anne Benedicte; Gluud, Christian; Wetterslev, Jørn

2005-01-01

To examine the availability and quality of clinical guidelines on perioperative diabetes care in hospital units before and after a randomised clinical trial (RCT) and international accreditation.......To examine the availability and quality of clinical guidelines on perioperative diabetes care in hospital units before and after a randomised clinical trial (RCT) and international accreditation....

Erythropoietin in traumatic brain injury: study protocol for a randomised controlled trial.

LENUS (Irish Health Repository)

Nichol, Alistair

2015-02-08

Traumatic brain injury is a leading cause of death and disability worldwide. Laboratory and clinical studies demonstrate a possible beneficial effect of erythropoietin in improving outcomes in the traumatic brain injury cohort. However, there are concerns regarding the association of erythropoietin and thrombosis in the critically ill. A large-scale, multi-centre, blinded, parallel-group, placebo-controlled, randomised trial is currently underway to address this hypothesis.

Cluster randomised controlled trial of 'whole school' child maltreatment prevention programme in primary schools in Northern Ireland: study protocol for Keeping Safe.

Science.gov (United States)

McElearney, Aisling; Brennan-Wilson, Aoibheann; Murphy, Christina; Stephenson, Phyllis; Bunting, Brendan

2018-05-03

Child maltreatment has a pervasive, detrimental impact on children's wellbeing. Despite a growing focus on prevention through school based education, few programmes adopt a whole- school approach, are multi-component, seek to address all forms of maltreatment, or indeed have been robustly evaluated. This paper describes a cluster randomised controlled trial designed to evaluate a school based child maltreatment prevention programme: 'Keeping Safe' in primary schools in Northern Ireland. The intervention has been designed by a non-profit agency. Programme resources include 63 lessons taught incrementally to children between four and 11 years old, and is premised on three core themes: healthy relationships, my body, and being safe. There are programme resources to engage parents and to build the capacity and skills of school staff. A cluster Randomised Controlled Trial (RCT) will be conducted with children in 80 schools over a two-year period. The unit of randomisation is the school. Schools will be allocated to intervention or wait-list control groups using a computer-generated list. Data will be collected at three time points: baseline, end of year one, and end of year two of programme implementation. Primary outcomes will include: children's understanding of key programme concepts, self-efficacy to keep safe in situations of maltreatment, anxiety arising from programme participation, and disclosure of maltreatment. Secondary outcomes include teachers' comfort and confidence in teaching the programme and parents' confidence in talking to their children about programme concepts. This RCT will address gaps in current practice and evidence regarding school based child maltreatment prevention programmes. This includes the use of a whole- school approach and multi-component programme that addresses all maltreatment concepts, a two-year period of programme implementation, and the tracking of outcomes for children, parents, and teachers. Methodologically, it will extend

Protocol for a multi-centre randomised controlled trial comparing arthroscopic hip surgery to physiotherapy-led care for femoroacetabular impingement (FAI): the Australian FASHIoN trial.

Science.gov (United States)

Murphy, Nicholas J; Eyles, Jillian; Bennell, Kim L; Bohensky, Megan; Burns, Alexander; Callaghan, Fraser M; Dickenson, Edward; Fary, Camdon; Grieve, Stuart M; Griffin, Damian R; Hall, Michelle; Hobson, Rachel; Kim, Young Jo; Linklater, James M; Lloyd, David G; Molnar, Robert; O'Connell, Rachel L; O'Donnell, John; O'Sullivan, Michael; Randhawa, Sunny; Reichenbach, Stephan; Saxby, David J; Singh, Parminder; Spiers, Libby; Tran, Phong; Wrigley, Tim V; Hunter, David J

2017-09-26

Femoroacetabular impingement syndrome (FAI), a hip disorder affecting active young adults, is believed to be a leading cause of hip osteoarthritis (OA). Current management approaches for FAI include arthroscopic hip surgery and physiotherapy-led non-surgical care; however, there is a paucity of clinical trial evidence comparing these approaches. In particular, it is unknown whether these management approaches modify the future risk of developing hip OA. The primary objective of this randomised controlled trial is to determine if participants with FAI who undergo hip arthroscopy have greater improvements in hip cartilage health, as demonstrated by changes in delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) index between baseline and 12 months, compared to those who undergo physiotherapy-led non-surgical management. This is a pragmatic, multi-centre, two-arm superiority randomised controlled trial comparing hip arthroscopy to physiotherapy-led management for FAI. A total of 140 participants with FAI will be recruited from the clinics of participating orthopaedic surgeons, and randomly allocated to receive either surgery or physiotherapy-led non-surgical care. The surgical intervention involves arthroscopic FAI surgery from one of eight orthopaedic surgeons specialising in this field, located in three different Australian cities. The physiotherapy-led non-surgical management is an individualised physiotherapy program, named Personalised Hip Therapy (PHT), developed by a panel to represent the best non-operative care for FAI. It entails at least six individual physiotherapy sessions over 12 weeks, and up to ten sessions over six months, provided by experienced musculoskeletal physiotherapists trained to deliver the PHT program. The primary outcome measure is the change in dGEMRIC score of a ROI containing both acetabular and femoral head cartilages at the chondrolabral transitional zone of the mid-sagittal plane between baseline and

START NOW - a comprehensive skills training programme for female adolescents with oppositional defiant and conduct disorders: study protocol for a cluster-randomised controlled trial.

Science.gov (United States)

Kersten, Linda; Prätzlich, Martin; Mannstadt, Sandra; Ackermann, Katharina; Kohls, Gregor; Oldenhof, Helena; Saure, Daniel; Krieger, Katrin; Herpertz-Dahlmann, Beate; Popma, Arne; Freitag, Christine M; Trestman, Robert L; Stadler, Christina

2016-12-01

In Europe, the number of females exhibiting oppositional defiant disorder (ODD) and conduct disorder (CD) is growing. Many of these females live in youth welfare institutions. Consequently, there is a great need for evidence-based interventions within youth welfare settings. A recently developed approach targeting the specific needs of girls with ODD and CD in residential care is START NOW. The aim of this group-based behavioural skills training programme is to specifically enhance emotional regulation capacities to enable females with CD or ODD to appropriately deal with daily-life demands. It is intended to enhance psychosocial adjustment and well-being as well as reduce oppositional and aggressive behaviour. We present the study protocol (version 4.1; 10 February 2016) of the FemNAT-CD intervention trial titled 'Group-Based Treatment of Adolescent Female Conduct Disorders: The Central Role of Emotion Regulation'. The study is a prospective, confirmatory, cluster-randomised, parallel-group, multi-centre, randomised controlled trial with 128 institutionalised female adolescents who fulfil the diagnostic criteria of ODD and/or CD. Institutions/wards will be randomised either to provide the 12-week skills training as an add-on intervention or to provide treatment as usual. Once the first cycle is completed, each institution will run a second cycle with the opposite condition. Primary endpoints are the pre-post change in number of CD/ODD symptoms as assessed by a standardised, semi-structured psychiatric interview (Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime, CD/ODD section) between baseline and the end of intervention, as well as between baseline and a 3-month follow-up point. Secondary objectives include pre-post change in CD/ODD-related outcome measures, most notably emotional regulation on a behavioural and neurobiological level after completion of START NOW compared with treatment as usual. To our

Group treatments for sensitive health care problems : a randomised controlled trial of group versus individual physiotherapy sessions for female urinary incontinence

OpenAIRE

Lamb, S. E. (Sallie E.); Pepper, Jo; Lall, Ranjit; Jørstad-Stein , Ellen C.; Clark, M. D. (Michael D.); Hill, Lesley; Fereday Smith, Jan

2009-01-01

Abstract Background The aim was to compare effectiveness of group versus individual sessions of physiotherapy in terms of symptoms, quality of life, and costs, and to investigate the effect of patient preference on uptake and outcome of treatment. Methods A pragmatic, multi-centre randomised controlled trial in five British National Health Service physiotherapy departments. 174 women with stress and/or urge incontinence were randomised to receive treatment from a physiotherapist delivered in ...

An imbalance in cluster sizes does not lead to notable loss of power in cross-sectional, stepped-wedge cluster randomised trials with a continuous outcome.

Science.gov (United States)

Kristunas, Caroline A; Smith, Karen L; Gray, Laura J

2017-03-07

The current methodology for sample size calculations for stepped-wedge cluster randomised trials (SW-CRTs) is based on the assumption of equal cluster sizes. However, as is often the case in cluster randomised trials (CRTs), the clusters in SW-CRTs are likely to vary in size, which in other designs of CRT leads to a reduction in power. The effect of an imbalance in cluster size on the power of SW-CRTs has not previously been reported, nor what an appropriate adjustment to the sample size calculation should be to allow for any imbalance. We aimed to assess the impact of an imbalance in cluster size on the power of a cross-sectional SW-CRT and recommend a method for calculating the sample size of a SW-CRT when there is an imbalance in cluster size. The effect of varying degrees of imbalance in cluster size on the power of SW-CRTs was investigated using simulations. The sample size was calculated using both the standard method and two proposed adjusted design effects (DEs), based on those suggested for CRTs with unequal cluster sizes. The data were analysed using generalised estimating equations with an exchangeable correlation matrix and robust standard errors. An imbalance in cluster size was not found to have a notable effect on the power of SW-CRTs. The two proposed adjusted DEs resulted in trials that were generally considerably over-powered. We recommend that the standard method of sample size calculation for SW-CRTs be used, provided that the assumptions of the method hold. However, it would be beneficial to investigate, through simulation, what effect the maximum likely amount of inequality in cluster sizes would be on the power of the trial and whether any inflation of the sample size would be required.

Re-weighted Discriminatively Embedded K-Means for Multi-view Clustering.

Science.gov (United States)

Xu, Jinglin; Han, Junwei; Nie, Feiping; Li, Xuelong

2017-02-08

Recent years, more and more multi-view data are widely used in many real world applications. This kind of data (such as image data) are high dimensional and obtained from different feature extractors, which represents distinct perspectives of the data. How to cluster such data efficiently is a challenge. In this paper, we propose a novel multi-view clustering framework, called Re-weighted Discriminatively Embedded KMeans (RDEKM), for this task. The proposed method is a multiview least-absolute residual model which induces robustness to efficiently mitigates the influence of outliers and realizes dimension reduction during multi-view clustering. Specifically, the proposed model is an unsupervised optimization scheme which utilizes Iterative Re-weighted Least Squares to solve leastabsolute residual and adaptively controls the distribution of multiple weights in a re-weighted manner only based on its own low-dimensional subspaces and a common clustering indicator matrix. Furthermore, theoretical analysis (including optimality and convergence analysis) and the optimization algorithm are also presented. Compared to several state-of-the-art multi-view clustering methods, the proposed method substantially improves the accuracy of the clustering results on widely used benchmark datasets, which demonstrates the superiority of the proposed work.

Probing the formation history of the nuclear star cluster at the Galactic Centre with millisecond pulsars

Science.gov (United States)

Abbate, F.; Mastrobuono-Battisti, A.; Colpi, M.; Possenti, A.; Sippel, A. C.; Dotti, M.

2018-01-01

The origin of the nuclear star cluster in the centre of our Galaxy is still unknown. One possibility is that it formed after the disruption of stellar clusters that spiralled into the Galactic Centre due to dynamical friction. We trace the formation of the nuclear star cluster around the central black hole, using state-of-the-art N-body simulations, and follow the dynamics of the neutron stars born in the clusters. We then estimate the number of millisecond pulsars (MSPs) that are released in the nuclear star cluster during its formation. The assembly and tidal dismemberment of globular clusters lead to a population of MSPs distributed over a radius of about 20 pc, with a peak near 3 pc. No clustering is found on the subparsec scale. We simulate the detectability of this population with future radio telescopes like the MeerKAT radio telescope and SKA1, and find that about an order of 10 MSPs can be observed over this large volume, with a paucity of MSPs within the central parsec. This helps discriminating this scenario from the in situ formation model for the nuclear star cluster that would predict an overabundance of MSPs closer to the black hole. We then discuss the potential contribution of our MSP population to the gamma-ray excess at the Galactic Centre.

Increasing physical activity in young primary school children-it's child's play: A cluster randomised controlled trial

NARCIS (Netherlands)

Engelen, L.; Bundy, A.C.; Naughton, G.; Simpson, J.M.; Bauman, A.; Ragen, J.; Baur, L.; Wyver, S.; Tranter, P.; Niehues, A.; Schiller, W.; Perry, G.; Jessup, G.; van der Ploeg, H.P.

2013-01-01

Objective: To explore the effects of an innovative school-based intervention for increasing physical activity. Methods: 226 children (5-7. years old) randomly selected from 12 Australian primary schools were recruited to a cluster randomised trial with schools randomly allocated to intervention or

Recommending the heterogeneous cluster type multi-processor system computing

International Nuclear Information System (INIS)

Iijima, Nobukazu

2010-01-01

Real-time reactor simulator had been developed by reusing the equipment of the Musashi reactor and its performance improvement became indispensable for research tools to increase sampling rate with introduction of arithmetic units using multi-Digital Signal Processor(DSP) system (cluster). In order to realize the heterogeneous cluster type multi-processor system computing, combination of two kinds of Control Processor (CP) s, Cluster Control Processor (CCP) and System Control Processor (SCP), were proposed with Large System Control Processor (LSCP) for hierarchical cluster if needed. Faster computing performance of this system was well evaluated by simulation results for simultaneous execution of plural jobs and also pipeline processing between clusters, which showed the system led to effective use of existing system and enhancement of the cost performance. (T. Tanaka)

Correlation between centre offsets and gas velocity dispersion of galaxy clusters in cosmological simulations

Science.gov (United States)

Li, Ming-Hua; Zhu, Weishan; Zhao, Dong

2018-05-01

The gas is the dominant component of baryonic matter in most galaxy groups and clusters. The spatial offsets of gas centre from the halo centre could be an indicator of the dynamical state of cluster. Knowledge of such offsets is important for estimate the uncertainties when using clusters as cosmological probes. In this paper, we study the centre offsets roff between the gas and that of all the matter within halo systems in ΛCDM cosmological hydrodynamic simulations. We focus on two kinds of centre offsets: one is the three-dimensional PB offsets between the gravitational potential minimum of the entire halo and the barycentre of the ICM, and the other is the two-dimensional PX offsets between the potential minimum of the halo and the iterative centroid of the projected synthetic X-ray emission of the halo. Haloes at higher redshifts tend to have larger values of rescaled offsets roff/r200 and larger gas velocity dispersion σ v^gas/σ _{200}. For both types of offsets, we find that the correlation between the rescaled centre offsets roff/r200 and the rescaled 3D gas velocity dispersion, σ _v^gas/σ _{200} can be approximately described by a quadratic function as r_{off}/r_{200} ∝ (σ v^gas/σ _{200} - k_2)2. A Bayesian analysis with MCMC method is employed to estimate the model parameters. Dependence of the correlation relation on redshifts and the gas mass fraction are also investigated.

Transvaginal prolapse repair with or without the addition of a midurethral sling in women with genital prolapse and stress urinary incontinence : a randomised trial

NARCIS (Netherlands)

van der Ploeg, J M; Oude Rengerink, K; van der Steen, A; van Leeuwen, J H S; Stekelenburg, J; Bongers, M Y; Weemhoff, M; Mol, B W; van der Vaart, C H; Roovers, J-P W R

OBJECTIVE: To compare transvaginal prolapse repair combined with midurethral sling (MUS) versus prolapse repair only. DESIGN: Multi-centre randomised trial. SETTING: Fourteen teaching hospitals in the Netherlands. POPULATION: Women with symptomatic stage two or greater pelvic organ prolapse (POP),

Transvaginal prolapse repair with or without the addition of a midurethral sling in women with genital prolapse and stress urinary incontinence: a randomised trial

NARCIS (Netherlands)

van der Ploeg, J. M.; Oude Rengerink, K.; van der Steen, A.; van Leeuwen, J. H. S.; Stekelenburg, J.; Bongers, M. Y.; Weemhoff, M.; Mol, B. W.; van der Vaart, C. H.; Roovers, J.-P. W. R.; Bergmans, Martin G.; Bongers, Marlies Y.; Dekker, Karin S.; van Gestel, Iris; Kluivers, Kirsten B.; Milani, A. L. Fred; van der Ploeg, J. Marinus; Oude Rengerink, Katrien; Schagen van Leeuwen, Jules H.; Schram, Aaltje J.; van der Steen, Annemarie; Stekelenburg, Jelle; van der Vaart, C. Huub; Weemhoff, Mirjam; Weis-Potters, Annemarie E.; Wijma, Jac

2015-01-01

To compare transvaginal prolapse repair combined with midurethral sling (MUS) versus prolapse repair only. Multi-centre randomised trial. Fourteen teaching hospitals in the Netherlands. Women with symptomatic stage two or greater pelvic organ prolapse (POP), and subjective or objective stress

Transvaginal prolapse repair with or without the addition of a midurethral sling in women with genital prolapse and stress urinary incontinence : a randomised trial

NARCIS (Netherlands)

van der Ploeg, J. M.; Rengerink, K. Oude; van der Steen, A.; van Leeuwen, J. H. S.; Stekelenburg, J.; Bongers, M. Y.; Weemhoff, M.; Mol, B. W.; van der Vaart, C. H.; Roovers, J-P W. R.

ObjectiveTo compare transvaginal prolapse repair combined with midurethral sling (MUS) versus prolapse repair only. DesignMulti-centre randomised trial. SettingFourteen teaching hospitals in the Netherlands. PopulationWomen with symptomatic stage two or greater pelvic organ prolapse (POP), and

Structures, energetics and magnetic properties of (NiSn) n clusters ...

Indian Academy of Sciences (India)

The preference for tetrahedron unit of Ni3 Sn is seen in the lowest-energy configuration of these clusters. The multi-centre bonding between Ni atoms play an important role in stabilizing the stoichiometric Ni–Sn clusters. Doping of Sn atoms enhances the binding energy and reduces the ionization potential of nickel clusters.

Clustering in surgical trials - database of intracluster correlations

Directory of Open Access Journals (Sweden)

Cook Jonathan A

2012-01-01

Full Text Available Abstract Background Randomised trials evaluation of surgical interventions are often designed and analysed as if the outcome of individual patients is independent of the surgeon providing the intervention. There is reason to expect outcomes for patients treated by the same surgeon tend to be more similar than those under the care of another surgeon due to previous experience, individual practice, training, and infrastructure. Such a phenomenon is referred to as the clustering effect and potentially impacts on the design and analysis adopted and thereby the required sample size. The aim of this work was to inform trial design by quantifying clustering effects (at both centre and surgeon level for various outcomes using a database of surgical trials. Methods Intracluster correlation coefficients (ICCs were calculated for outcomes from a set of 10 multicentre surgical trials for a range of outcomes and different time points for clustering at both the centre and surgeon level. Results ICCs were calculated for 198 outcomes across the 10 trials at both centre and surgeon cluster levels. The number of cases varied from 138 to 1370 across the trials. The median (range average cluster size was 32 (9 to 51 and 6 (3 to 30 for centre and surgeon levels respectively. ICC estimates varied substantially between outcome type though uncertainty around individual ICC estimates was substantial, which was reflected in generally wide confidence intervals. Conclusions This database of surgical trials provides trialists with valuable information on how to design surgical trials. Our data suggests clustering of outcome is more of an issue than has been previously acknowledged. We anticipate that over time the addition of ICCs from further surgical trial datasets to our database will further inform the design of surgical trials.

A designated centre for people with disabilities operated by Muiríosa Foundation, Westmeath

LENUS (Irish Health Repository)

Nichol, Alistair

2015-02-08

Traumatic brain injury is a leading cause of death and disability worldwide. Laboratory and clinical studies demonstrate a possible beneficial effect of erythropoietin in improving outcomes in the traumatic brain injury cohort. However, there are concerns regarding the association of erythropoietin and thrombosis in the critically ill. A large-scale, multi-centre, blinded, parallel-group, placebo-controlled, randomised trial is currently underway to address this hypothesis.

Getting better at chronic care in remote communities: study protocol for a pragmatic cluster randomised controlled of community based management.

Science.gov (United States)

Schmidt, Barbara; Wenitong, Mark; Esterman, Adrian; Hoy, Wendy; Segal, Leonie; Taylor, Sean; Preece, Cilla; Sticpewich, Alex; McDermott, Robyn

2012-11-21

Prevalence and incidence of diabetes and other common comorbid conditions (hypertension, coronary heart disease, renal disease and chronic lung disease) are extremely high among Indigenous Australians. Recent measures to improve quality of preventive care in Indigenous community settings, while apparently successful at increasing screening and routine check-up rates, have shown only modest or little improvements in appropriate care such as the introduction of insulin and other scaled-up drug regimens in line with evidence-based guidelines, together with support for risk factor reduction. A new strategy is required to ensure high quality integrated family-centred care is available locally, with continuity and cultural safety, by community-based care coordinators with appropriate system supports. The trial design is open parallel cluster randomised controlled trial. The objective of this pragmatic trial is to test the effectiveness of a model of health service delivery that facilitates integrated community-based, intensive chronic condition management, compared with usual care, in rural and remote Indigenous primary health care services in north Queensland. Participants are Indigenous adults (aged 18-65 years) with poorly controlled diabetes (HbA1c>=8.5) and at least one other chronic condition. The intervention is to employ an Indigenous Health Worker to case manage the care of a maximum caseload of 30 participants. The Indigenous Health Workers receive intensive clinical training initially, and throughout the study, to ensure they are competent to coordinate care for people with chronic conditions. The Indigenous Health Workers, supported by the local primary health care (PHC) team and an Indigenous Clinical Support Team, will manage care, including coordinating access to multidisciplinary team care based on best practice standards. Allocation by cluster to the intervention and control groups is by simple randomisation after participant enrolment. Participants in

Efficacy and effectiveness of an rVSV-vectored vaccine expressing Ebola surface glycoprotein: interim results from the Guinea ring vaccination cluster-randomised trial.

Science.gov (United States)

Henao-Restrepo, Ana Maria; Longini, Ira M; Egger, Matthias; Dean, Natalie E; Edmunds, W John; Camacho, Anton; Carroll, Miles W; Doumbia, Moussa; Draguez, Bertrand; Duraffour, Sophie; Enwere, Godwin; Grais, Rebecca; Gunther, Stephan; Hossmann, Stefanie; Kondé, Mandy Kader; Kone, Souleymane; Kuisma, Eeva; Levine, Myron M; Mandal, Sema; Norheim, Gunnstein; Riveros, Ximena; Soumah, Aboubacar; Trelle, Sven; Vicari, Andrea S; Watson, Conall H; Kéïta, Sakoba; Kieny, Marie Paule; Røttingen, John-Arne

2015-08-29

these clusters (4123 people) were randomly assigned to immediate vaccination with rVSV-ZEBOV, and 42 clusters (3528 people) were randomly assigned to delayed vaccination with rVSV-ZEBOV. In the immediate vaccination group, there were no cases of Ebola virus disease with symptom onset at least 10 days after randomisation, whereas in the delayed vaccination group there were 16 cases of Ebola virus disease from seven clusters, showing a vaccine efficacy of 100% (95% CI 74·7-100·0; p=0·0036). No new cases of Ebola virus disease were diagnosed in vaccinees from the immediate or delayed groups from 6 days post-vaccination. At the cluster level, with the inclusion of all eligible adults, vaccine effectiveness was 75·1% (95% CI -7·1 to 94·2; p=0·1791), and 76·3% (95% CI -15·5 to 95·1; p=0·3351) with the inclusion of everyone (eligible or not eligible for vaccination). 43 serious adverse events were reported; one serious adverse event was judged to be causally related to vaccination (a febrile episode in a vaccinated participant, which resolved without sequelae). Assessment of serious adverse events is ongoing. The results of this interim analysis indicate that rVSV-ZEBOV might be highly efficacious and safe in preventing Ebola virus disease, and is most likely effective at the population level when delivered during an Ebola virus disease outbreak via a ring vaccination strategy. WHO, with support from the Wellcome Trust (UK); Médecins Sans Frontières; the Norwegian Ministry of Foreign Affairs through the Research Council of Norway; and the Canadian Government through the Public Health Agency of Canada, Canadian Institutes of Health Research, International Development Research Centre, and Department of Foreign Affairs, Trade and Development. Copyright © 2015 World Health Organization. Published by Elsevier Ltd/Inc/BV. All rights reserved. Published by Elsevier Ltd.. All rights reserved.

A pragmatic multi-centre randomised controlled trial of fluid loading in high-risk surgical patients undergoing major elective surgery--the FOCCUS study.

Science.gov (United States)

Cuthbertson, Brian H; Campbell, Marion K; Stott, Stephen A; Elders, Andrew; Hernández, Rodolfo; Boyers, Dwayne; Norrie, John; Kinsella, John; Brittenden, Julie; Cook, Jonathan; Rae, Daniela; Cotton, Seonaidh C; Alcorn, David; Addison, Jennifer; Grant, Adrian

2011-01-01

Fluid strategies may impact on patient outcomes in major elective surgery. We aimed to study the effectiveness and cost-effectiveness of pre-operative fluid loading in high-risk surgical patients undergoing major elective surgery. This was a pragmatic, non-blinded, multi-centre, randomised, controlled trial. We sought to recruit 128 consecutive high-risk surgical patients undergoing major abdominal surgery. The patients underwent pre-operative fluid loading with 25 ml/kg of Ringer's solution in the six hours before surgery. The control group had no pre-operative fluid loading. The primary outcome was the number of hospital days after surgery with cost-effectiveness as a secondary outcome. A total of 111 patients were recruited within the study time frame in agreement with the funder. The median pre-operative fluid loading volume was 1,875 ml (IQR 1,375 to 2,025) in the fluid group compared to 0 (IQR 0 to 0) in controls with days in hospital after surgery 12.2 (SD 11.5) days compared to 17.4 (SD 20.0) and an adjusted mean difference of 5.5 days (median 2.2 days; 95% CI -0.44 to 11.44; P = 0.07). There was a reduction in adverse events in the fluid intervention group (P = 0.048) and no increase in fluid based complications. The intervention was less costly and more effective (adjusted average cost saving: £2,047; adjusted average gain in benefit: 0.0431 quality adjusted life year (QALY)) and has a high probability of being cost-effective. Pre-operative intravenous fluid loading leads to a non-significant reduction in hospital length of stay after high-risk major surgery and is likely to be cost-effective. Confirmatory work is required to determine whether these effects are reproducible, and to confirm whether this simple intervention could allow more cost-effective delivery of care. Prospective Clinical Trials, ISRCTN32188676.

A luminous X-ray outburst from an intermediate-mass black hole in an off-centre star cluster

Science.gov (United States)

Lin, Dacheng; Strader, Jay; Carrasco, Eleazar R.; Page, Dany; Romanowsky, Aaron J.; Homan, Jeroen; Irwin, Jimmy A.; Remillard, Ronald A.; Godet, Olivier; Webb, Natalie A.; Baumgardt, Holger; Wijnands, Rudy; Barret, Didier; Duc, Pierre-Alain; Brodie, Jean P.; Gwyn, Stephen D. J.

2018-06-01

A unique signature for the presence of massive black holes in very dense stellar regions is occasional giant-amplitude outbursts of multi-wavelength radiation from tidal disruption and subsequent accretion of stars that make a close approach to the black holes1. Previous strong tidal disruption event (TDE) candidates were all associated with the centres of largely isolated galaxies2-6. Here, we report the discovery of a luminous X-ray outburst from a massive star cluster at a projected distance of 12.5 kpc from the centre of a large lenticular galaxy. The luminosity peaked at 1043 erg s-1 and decayed systematically over 10 years, approximately following a trend that supports the identification of the event as a TDE. The X-ray spectra were all very soft, with emission confined to be ≲3.0 keV, and could be described with a standard thermal disk. The disk cooled significantly as the luminosity decreased—a key thermal-state signature often observed in accreting stellar-mass black holes. This thermal-state signature, coupled with very high luminosities, ultrasoft X-ray spectra and the characteristic power-law evolution of the light curve, provides strong evidence that the source contains an intermediate-mass black hole with a mass tens of thousand times that of the solar mass. This event demonstrates that one of the most effective means of detecting intermediate-mass black holes is through X-ray flares from TDEs in star clusters.

Information and Choice of A-Level Subjects: A Cluster Randomised Controlled Trial with Linked Administrative Data

Science.gov (United States)

Davies, Peter; Davies, Neil M.; Qiu, Tian

2017-01-01

We estimated the effects of an intervention which provided information about graduate wages to 5593 students in England, using a blinded cluster randomised controlled trial in 50 schools (registration: AEARCTR-0000468). Our primary outcome was students' choice of A-level subjects at age 16. We also recorded the students' expectations of future…

Shared Decision Making in mental health care using Routine Outcome Monitoring as a source of information: a cluster randomised controlled trial.

Science.gov (United States)

Metz, Margot J; Franx, Gerdien C; Veerbeek, Marjolein A; de Beurs, Edwin; van der Feltz-Cornelis, Christina M; Beekman, Aartjan T F

2015-12-15

Shared Decision Making (SDM) is a way to empower patients when decisions are made about treatment. In order to be effective agents in this process, patients need access to information of good quality. Routine Outcome Monitoring (ROM) may provide such information and therefore may be a key element in SDM. This trial tests the effectiveness of SDM using ROM, primarily aiming to diminish decisional conflict of the patient while making decisions about treatment. The degree of decisional conflict, the primary outcome of this study, encompasses personal certainty about choosing an appropriate treatment, information about options, clarification of patient values, support from others and patients experience of an effective decision making process. Secondary outcomes of the study focus on the working alliance between patient and clinician, adherence to treatment, and clinical outcome and quality of life. This article presents the study protocol of a multi-centre two-arm cluster randomised controlled trial (RCT). The research is conducted in Dutch specialised mental health care teams participating in the ROM Quality Improvement Collaborative (QIC), which aims to implement ROM in daily clinical practice. In the intervention teams, ROM is used as a source of information during the SDM process between the patient and clinician. Control teams receive no specific SDM or ROM instructions and apply decision making as usual. Randomisation is conducted at the level of the participating teams within the mental health organisations. A total of 12 teams from 4 organisations and 364 patients participate in the study. Prior to data collection, the intervention teams are trained to use ROM during the SDM process. Data collection will be at baseline, and at 3 and 6 months after inclusion of the patient. Control teams will implement the SDM and ROM model after completion of the study. This study will provide useful information about the effectiveness of ROM within a SDM framework

The effectiveness of a clinically integrated e-learning course in evidence-based medicine: A cluster randomised controlled trial

NARCIS (Netherlands)

Kulier, Regina; Coppus, Sjors F. P. J.; Zamora, Javier; Hadley, Julie; Malick, Sadia; Das, Kausik; Weinbrenner, Susanne; Meyerrose, Berrit; Decsi, Tamas; Horvath, Andrea R.; Nagy, Eva; Emparanza, Jose I.; Arvanitis, Theodoros N.; Burls, Amanda; Cabello, Juan B.; Kaczor, Marcin; Zanrei, Gianni; Pierer, Karen; Stawiarz, Katarzyna; Kunz, Regina; Mol, Ben W. J.; Khan, Khalid S.

2009-01-01

ABSTRACT: BACKGROUND: To evaluate the educational effects of a clinically integrated e-learning course for teaching basic evidence-based medicine (EBM) among postgraduates compared to a traditional lecture-based course of equivalent content. METHODS: We conducted a cluster randomised controlled

Fostering Effective Early Learning (FEEL) through a professional development programme for early childhood educators to improve professional practice and child outcomes in the year before formal schooling: study protocol for a cluster randomised controlled trial.

Science.gov (United States)

Melhuish, Edward; Howard, Steven J; Siraj, Iram; Neilsen-Hewett, Cathrine; Kingston, Denise; de Rosnay, Marc; Duursma, Elisabeth; Luu, Betty

2016-12-19

A substantial research base documents the benefits of attendance at high-quality early childhood education and care (ECEC) for positive behavioural and learning outcomes. Research has also found that the quality of many young children's experiences and opportunities in ECEC depends on the skills, dispositions and understandings of the early childhood adult educators. Increasingly, research has shown that the quality of children's interactions with educators and their peers, more than any other programme feature, influence what children learn and how they feel about learning. Hence, we sought to investigate the extent to which evidence-based professional development (PD) - focussed on promoting sustained shared thinking through quality interactions - could improve the quality of ECEC and, as a consequence, child outcomes. The Fostering Effective Early Learning (FEEL) study is a cluster randomised controlled trial for evaluating the benefits of a professional development (PD) programme for early childhood educators, compared with no extra PD. Ninety long-day care and preschool centres in New South Wales, Australia, will be selected to ensure representation across National Quality Standards (NQS) ratings, location, centre type and socioeconomic areas. Participating centres will be randomly allocated to one of two groups, stratified by centre type and NQS rating: (1) an intervention group (45 centres) receiving a PD intervention or (2) a control group (45 centres) that continues engaging in typical classroom practice. Randomisation to these groups will occur after the collection of baseline environmental quality ratings. Primary outcomes, at the child level, will be two measures of language development: verbal comprehension and expressive vocabulary. Secondary outcomes at the child level will be measures of early numeracy, social development and self-regulation. Secondary outcomes at the ECEC room level will be measures of environmental quality derived from full

Effectiveness of structured patient-clinician communication with a solution focused approach (DIALOG+) in community treatment of patients with psychosis--a cluster randomised controlled trial.

Science.gov (United States)

Priebe, Stefan; Kelley, Lauren; Golden, Eoin; McCrone, Paul; Kingdon, David; Rutterford, Clare; McCabe, Rosemarie

2013-06-26

Large numbers of patients with psychosis have regular meetings with key clinicians in the community. There is little evidence on how these meetings should be conducted to be therapeutically effective. DIALOG, a computer mediated procedure, was shown to improve outcomes in a European multi-centre trial. DIALOG structures the patient-clinician communication and makes it patient-centred, but does not guide clinicians as to how to respond to patients' concerns. DIALOG has been further developed into DIALOG+, which uses advanced software and, additionally, provides a four step approach--based on a solution focused model--for addressing patients' concerns. We designed a cluster randomised controlled trial to test the effectiveness of DIALOG+ in improving treatment outcomes of patients with psychosis in the community. Key workers are recruited from community mental health teams in East London and randomly allocated to either the intervention or control group. Out of their case loads, we identify patients with schizophrenia (F 20-29) and a moderate or lower level of subjective quality of life (MANSA score workers. Key workers in the intervention group are trained in using DIALOG+ and use it with each patient over a six-month period. Control patients rate their satisfaction with life and treatment on a tablet to control for the effect of regular ratings and the use of modern technology. We are recruiting up to 42 key workers to reach a total sample size of 180 patients. Clinical and social outcomes including costs are assessed after 3, 6 and 12 months. Primary outcome is subjective quality-of-life at 6 months. The trial aims to evaluate the effectiveness of a novel intervention (DIALOG+) which uses modern technology to support routine patient-clinician meetings in community care, makes the communication patient centred and guides patients and clinicians to address concerns. DIALOG+ is a generic and widely applicable intervention. If shown as effective, it can be used to

A cluster-randomised, controlled trial to assess the impact of a workplace osteoporosis prevention intervention on the dietary and physical activity behaviours of working women: study protocol

OpenAIRE

Tan, Ai May; LaMontagne, Anthony D; Sarmugam, Rani; Howard, Peter

2013-01-01

Background Osteoporosis is a debilitating disease and its risk can be reduced through adequate calcium consumption and physical activity. This protocol paper describes a workplace-based intervention targeting behaviour change in premenopausal women working in sedentary occupations. Method/Design A cluster-randomised design was used, comparing the efficacy of a tailored intervention to standard care. Workplaces were the clusters and units of randomisation and intervention. Sample size calculat...

Text messaging reminders for influenza vaccine in primary care: protocol for a cluster randomised controlled trial (TXT4FLUJAB).

Science.gov (United States)

Herrett, Emily; van Staa, Tjeerd; Free, Caroline; Smeeth, Liam

2014-05-02

The UK government recommends that at least 75% of people aged under 64 with certain conditions receive an annual influenza vaccination. Primary care practices often fall short of this target and strategies to increase vaccine uptake are required. Text messaging reminders are already used in 30% of practices to remind patients about vaccination, but there has been no trial addressing their effectiveness in increasing influenza vaccine uptake in the UK. The aims of the study are (1) to develop the methodology for conducting cluster randomised trials of text messaging interventions utilising routine electronic health records and (2) to assess the effectiveness of using a text messaging influenza vaccine reminder in achieving an increase in influenza vaccine uptake in patients aged 18-64 with chronic conditions, compared with standard care. This cluster randomised trial will recruit general practices across three settings in English primary care (Clinical Practice Research Datalink, ResearchOne and London iPLATO text messaging software users) and randomise them to either standard care or a text messaging campaign to eligible patients. Flu vaccine uptake will be ascertained using routinely collected, anonymised electronic patient records. This protocol outlines the proposed study design and analysis methods. This study will determine the effectiveness of text messaging vaccine reminders in primary care in increasing influenza vaccine uptake, and will strengthen the methodology for using electronic health records in cluster randomised trials of text messaging interventions. This trial was approved by the Surrey Borders Ethics Committee (13/LO/0872). The trial results will be disseminated at national conferences and published in a peer-reviewed medical journal. The results will also be distributed to the Primary Care Research Network and to all participating general practices. This study is registered at controlled-trials.com ISRCTN48840025, July 2013.

Sample size calculations for cluster randomised crossover trials in Australian and New Zealand intensive care research.

Science.gov (United States)

Arnup, Sarah J; McKenzie, Joanne E; Pilcher, David; Bellomo, Rinaldo; Forbes, Andrew B

2018-06-01

The cluster randomised crossover (CRXO) design provides an opportunity to conduct randomised controlled trials to evaluate low risk interventions in the intensive care setting. Our aim is to provide a tutorial on how to perform a sample size calculation for a CRXO trial, focusing on the meaning of the elements required for the calculations, with application to intensive care trials. We use all-cause in-hospital mortality from the Australian and New Zealand Intensive Care Society Adult Patient Database clinical registry to illustrate the sample size calculations. We show sample size calculations for a two-intervention, two 12-month period, cross-sectional CRXO trial. We provide the formulae, and examples of their use, to determine the number of intensive care units required to detect a risk ratio (RR) with a designated level of power between two interventions for trials in which the elements required for sample size calculations remain constant across all ICUs (unstratified design); and in which there are distinct groups (strata) of ICUs that differ importantly in the elements required for sample size calculations (stratified design). The CRXO design markedly reduces the sample size requirement compared with the parallel-group, cluster randomised design for the example cases. The stratified design further reduces the sample size requirement compared with the unstratified design. The CRXO design enables the evaluation of routinely used interventions that can bring about small, but important, improvements in patient care in the intensive care setting.

Multi-disciplinary facilities at the centre for nuclear sciences, U.W.I

International Nuclear Information System (INIS)

Lalor, G.C.; Robotham, H.

1994-01-01

The Centre for Nuclear Sciences was established in 1984 with the mandate to introduce Caribbean scientists to the application of nuclear technology in multi-disciplinary studies, and to carry out research in areas of national and regional importance. It describes the present facilities and the major programmes being carried out at the Centre. (author) 9 refs

A structural multidisciplinary approach to depression management in nursing-home residents: a multicentre, stepped-wedge cluster-randomised trial

NARCIS (Netherlands)

Leontjevas, R.; Gerritsen, D.L.; Smalbrugge, M.; Teerenstra, S.; Vernooij-Dassen, M.J.F.J.; Koopmans, R.T.C.M.

2013-01-01

BACKGROUND: Depression in nursing-home residents is often under-recognised. We aimed to establish the effectiveness of a structural approach to its management. METHODS: Between May 15, 2009, and April 30, 2011, we undertook a multicentre, stepped-wedge cluster-randomised trial in four provinces of

Distributed Scheduling to Support a Call Centre: a Co-operative Multi-Agent Approach

NARCIS (Netherlands)

Brazier, F.M.; Jonker, C.M.; Jungen, F.J.; Treur, J.; Nwana, H.S.

1998-01-01

This paper describes a multi-agent system architecture to increase the value of 24 hour a day call centre service. This system supports call centres in making appointments with clients on the basis of knowledge of employees and their schedules. Relevant activities of employees are scheduled for

MULTI-K: accurate classification of microarray subtypes using ensemble k-means clustering

Directory of Open Access Journals (Sweden)

Ashlock Daniel

2009-08-01

Full Text Available Abstract Background Uncovering subtypes of disease from microarray samples has important clinical implications such as survival time and sensitivity of individual patients to specific therapies. Unsupervised clustering methods have been used to classify this type of data. However, most existing methods focus on clusters with compact shapes and do not reflect the geometric complexity of the high dimensional microarray clusters, which limits their performance. Results We present a cluster-number-based ensemble clustering algorithm, called MULTI-K, for microarray sample classification, which demonstrates remarkable accuracy. The method amalgamates multiple k-means runs by varying the number of clusters and identifies clusters that manifest the most robust co-memberships of elements. In addition to the original algorithm, we newly devised the entropy-plot to control the separation of singletons or small clusters. MULTI-K, unlike the simple k-means or other widely used methods, was able to capture clusters with complex and high-dimensional structures accurately. MULTI-K outperformed other methods including a recently developed ensemble clustering algorithm in tests with five simulated and eight real gene-expression data sets. Conclusion The geometric complexity of clusters should be taken into account for accurate classification of microarray data, and ensemble clustering applied to the number of clusters tackles the problem very well. The C++ code and the data sets tested are available from the authors.

MULTI-K: accurate classification of microarray subtypes using ensemble k-means clustering.

Science.gov (United States)

Kim, Eun-Youn; Kim, Seon-Young; Ashlock, Daniel; Nam, Dougu

2009-08-22

Uncovering subtypes of disease from microarray samples has important clinical implications such as survival time and sensitivity of individual patients to specific therapies. Unsupervised clustering methods have been used to classify this type of data. However, most existing methods focus on clusters with compact shapes and do not reflect the geometric complexity of the high dimensional microarray clusters, which limits their performance. We present a cluster-number-based ensemble clustering algorithm, called MULTI-K, for microarray sample classification, which demonstrates remarkable accuracy. The method amalgamates multiple k-means runs by varying the number of clusters and identifies clusters that manifest the most robust co-memberships of elements. In addition to the original algorithm, we newly devised the entropy-plot to control the separation of singletons or small clusters. MULTI-K, unlike the simple k-means or other widely used methods, was able to capture clusters with complex and high-dimensional structures accurately. MULTI-K outperformed other methods including a recently developed ensemble clustering algorithm in tests with five simulated and eight real gene-expression data sets. The geometric complexity of clusters should be taken into account for accurate classification of microarray data, and ensemble clustering applied to the number of clusters tackles the problem very well. The C++ code and the data sets tested are available from the authors.

Coronary CT angiography using 64 detector rows: methods and design of the multi-centre trial CORE-64

Energy Technology Data Exchange (ETDEWEB)

Miller, Julie M.; Vavere, Andrea L.; Arbab-Zadeh, Armin; Bush, David E.; Lardo, Albert C.; Texter, John; Brinker, Jeffery; Lima, Joao A.C. [Johns Hopkins Hospital, Johns Hopkins University, Department of Medicine, Division of Cardiology, Baltimore, MD (United States); Dewey, Marc [Charite - Universitaetsmedizin Berlin, Medical School, Humboldt-Universitaet und Freie Universitaet zu Berlin, Department of Radiology, Berlin, PO Box 10098 (Germany); Rochitte, Carlos E.; Lemos, Pedro A. [University of Sao Paulo Medical School, Heart Institute (InCor), Sao Paulo (Brazil); Niinuma, Hiroyuki [Iwate Medical University, Department of Cardiology, Morioka (Japan); Paul, Narinder [Toronto General Hospital, Department of Medical Imaging, Toronto (Canada); Hoe, John [Medi-Rad Associates Ltd, CT Centre, Mt Elizabeth Hospital, Singapore (Singapore); Roos, Albert de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Yoshioka, Kunihiro [Iwate Medical University, Department of Radiology, Morioka (Japan); Cox, Christopher [Johns Hopkins Bloomberg School of Public Health, Department of Epidemiology, Baltimore, MD (United States); Clouse, Melvin E. [Harvard University, Department of Radiology, Beth Israel Deaconess, Boston, MA (United States)

2009-04-15

Multislice computed tomography (MSCT) for the noninvasive detection of coronary artery stenoses is a promising candidate for widespread clinical application because of its non-invasive nature and high sensitivity and negative predictive value as found in several previous studies using 16 to 64 simultaneous detector rows. A multi-centre study of CT coronary angiography using 16 simultaneous detector rows has shown that 16-slice CT is limited by a high number of nondiagnostic cases and a high false-positive rate. A recent meta-analysis indicated a significant interaction between the size of the study sample and the diagnostic odds ratios suggestive of small study bias, highlighting the importance of evaluating MSCT using 64 simultaneous detector rows in a multi-centre approach with a larger sample size. In this manuscript we detail the objectives and methods of the prospective ''CORE-64'' trial (''Coronary Evaluation Using Multidetector Spiral Computed Tomography Angiography using 64 Detectors''). This multi-centre trial was unique in that it assessed the diagnostic performance of 64-slice CT coronary angiography in nine centres worldwide in comparison to conventional coronary angiography. In conclusion, the multi-centre, multi-institutional and multi-continental trial CORE-64 has great potential to ultimately assess the per-patient diagnostic performance of coronary CT angiography using 64 simultaneous detector rows. (orig.)

Uplink multi-cluster scheduling with MU-MIMO for LTE-advanced with carrier aggregation

DEFF Research Database (Denmark)

Wang, Hua; Nguyen, Hung Tuan; Rosa, Claudio

2012-01-01

-Advanced requirements and are being considered as part of LTE Release 10. In this paper, some of the physical layer enhancement techniques for LTE-Advanced have been studied including carrier aggregation (CA), uplink multi-cluster scheduling, and uplink multi-user multiple-input multiple-output (MU-MIMO) transmission....... A system-level simulation was conducted to investigate the performance gains that can be achieved in uplink CA with multi-cluster scheduling and MU-MIMO. Simulation results show that with proper separation between power-limited and non-power-limited LTE-A users, multi-cluster scheduling with CA has similar...

The effect of TCM acupuncture on hot flushes among menopausal women (ACUFLASH study: A study protocol of an ongoing multi-centre randomised controlled clinical trial

Directory of Open Access Journals (Sweden)

Borud Einar K

2007-02-01

Full Text Available Abstract Background After menopause, 10–20% of all women have nearly intolerable hot flushes. Long term use of hormone replacement therapy involves a health risk, and many women seek alternative strategies to relieve climacteric complaints. Acupuncture is one of the most frequently used complementary therapies in Norway. We designed a study to evaluate whether Traditional Chinese Medicine acupuncture-care together with self-care is more effective than self-care alone to relieve climacteric complaints. Methods/Design The study is a multi-centre pragmatic randomised controlled trial with two parallel arms. Participants are postmenopausal women who document ≥7 flushes/24 hours and who are not using hormone replacement therapy or other medication that may influence flushes. According to power calculations 200 women are needed to detect a 50% reduction in flushes, and altogether 286 women will be recruited to allow for a 30% dropout rate. The treatment group receives 10 sessions of Traditional Chinese Medicine acupuncture-care and self-care; the control group will engage in self-care only. A team of experienced Traditional Chinese Medicine acupuncturists give acupuncture treatments. Discussion The study tests acupuncture as a complete treatment package including the therapeutic relationship and expectation. The intervention period lasts for 12 weeks, with follow up at 6 and 12 months. Primary endpoint is change in daily hot flush frequency in the two groups from baseline to 12 weeks; secondary endpoint is health related quality of life, assessed by the Women's Health Questionnaire. We also collect data on Traditional Chinese Medicine diagnoses, and we examine treatment experiences using a qualitative approach. Finally we measure biological variables, to examine potential mechanisms for the effect of acupuncture. The study is funded by The Research Council of Norway.

Preventing Weight Gain in Women in Rural Communities: A Cluster Randomised Controlled Trial.

Directory of Open Access Journals (Sweden)

Catherine Lombard

2016-01-01

Full Text Available Obesity is reaching epidemic proportions in both developed and developing countries. Even modest weight gain increases the risk for chronic illness, yet evidence-based interventions to prevent weight gain are rare. This trial will determine if a simple low-intensity intervention can prevent weight gain in women compared to general health information.We conducted a 1-yr pragmatic, cluster randomised controlled trial in 41 Australian towns (clusters randomised using a computer-generated randomisation list for intervention (n = 21 or control (n = 20. Women aged 18 to 50 yr were recruited from the general population to receive a 1-yr self-management lifestyle intervention (HeLP-her consisting of one group session, monthly SMS text messages, one phone coaching session, and a program manual, or to a control group receiving one general women's health education session. From October 2012 to April 2014 we studied 649 women, mean age 39.6 yr (+/- SD 6.7 and BMI of 28.8 kg/m(2 (+/- SD 6.9 with the primary outcome weight change between groups at 1 yr. The mean change in the control was +0.44 kg (95% CI -0.09 to 0.97 and in the intervention group -0.48 kg (95% CI -0.99 to 0.03 with an unadjusted between group difference of -0.92 kg (95% CI -1.67 to -0.16 or -0.87 kg (95% CI -1.62 to -0.13 adjusted for baseline values and clustering. Secondary outcomes included improved diet quality and greater self-management behaviours. The intervention appeared to be equally efficacious across all age, BMI, income, and education subgroups. Loss to follow-up included 23.8% in the intervention group and 21.8% in the control group and was within the anticipated range. Limitations include lack of sensitive tools to measure the small changes to energy intake and physical activity. Those who gained weight may have been less inclined to return for 1 yr weight measures.A low intensity lifestyle program can prevent the persistent weight gain observed in women. Key features included

The Infant Feeding Activity and Nutrition Trial (INFANT an early intervention to prevent childhood obesity: Cluster-randomised controlled trial

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Campbell Karen

2008-03-01

Full Text Available Abstract Background Multiple factors combine to support a compelling case for interventions that target the development of obesity-promoting behaviours (poor diet, low physical activity and high sedentary behaviour from their inception. These factors include the rapidly increasing prevalence of fatness throughout childhood, the instigation of obesity-promoting behaviours in infancy, and the tracking of these behaviours from childhood through to adolescence and adulthood. The Infant Feeding Activity and Nutrition Trial (INFANT aims to determine the effectiveness of an early childhood obesity prevention intervention delivered to first-time parents. The intervention, conducted with parents over the infant's first 18 months of life, will use existing social networks (first-time parent's groups and an anticipatory guidance framework focusing on parenting skills which support the development of positive diet and physical activity behaviours, and reduced sedentary behaviours in infancy. Methods/Design This cluster-randomised controlled trial, with first-time parent groups as the unit of randomisation, will be conducted with a sample of 600 first-time parents and their newborn children who attend the first-time parents' group at Maternal and Child Health Centres. Using a two-stage sampling process, local government areas in Victoria, Australia will be randomly selected at the first stage. At the second stage, a proportional sample of first-time parent groups within selected local government areas will be randomly selected and invited to participate. Informed consent will be obtained and groups will then be randomly allocated to the intervention or control group. Discussion The early years hold promise as a time in which obesity prevention may be most effective. To our knowledge this will be the first randomised trial internationally to demonstrate whether an early health promotion program delivered to first-time parents in their existing social groups

Head Position in Stroke Trial (HeadPoST)--sitting-up vs lying-flat positioning of patients with acute stroke: study protocol for a cluster randomised controlled trial.

Science.gov (United States)

Muñoz-Venturelli, Paula; Arima, Hisatomi; Lavados, Pablo; Brunser, Alejandro; Peng, Bin; Cui, Liying; Song, Lily; Billot, Laurent; Boaden, Elizabeth; Hackett, Maree L; Heritier, Stephane; Jan, Stephen; Middleton, Sandy; Olavarría, Verónica V; Lim, Joyce Y; Lindley, Richard I; Heeley, Emma; Robinson, Thompson; Pontes-Neto, Octavio; Natsagdorj, Lkhamtsoo; Lin, Ruey-Tay; Watkins, Caroline; Anderson, Craig S

2015-06-05

Positioning a patient lying-flat in the acute phase of ischaemic stroke may improve recovery and reduce disability, but such a possibility has not been formally tested in a randomised trial. We therefore initiated the Head Position in Stroke Trial (HeadPoST) to determine the effects of lying-flat (0°) compared with sitting-up (≥ 30°) head positioning in the first 24 hours of hospital admission for patients with acute stroke. We plan to conduct an international, cluster randomised, crossover, open, blinded outcome-assessed clinical trial involving 140 study hospitals (clusters) with established acute stroke care programs. Each hospital will be randomly assigned to sequential policies of lying-flat (0°) or sitting-up (≥ 30°) head position as a 'business as usual' stroke care policy during the first 24 hours of admittance. Each hospital is required to recruit 60 consecutive patients with acute ischaemic stroke (AIS), and all patients with acute intracerebral haemorrhage (ICH) (an estimated average of 10), in the first randomised head position policy before crossing over to the second head position policy with a similar recruitment target. After collection of in-hospital clinical and management data and 7-day outcomes, central trained blinded assessors will conduct a telephone disability assessment with the modified Rankin Scale at 90 days. The primary outcome for analysis is a shift (defined as improvement) in death or disability on this scale. For a cluster size of 60 patients with AIS per intervention and with various assumptions including an intracluster correlation coefficient of 0.03, a sample size of 16,800 patients at 140 centres will provide 90 % power (α 0.05) to detect at least a 16 % relative improvement (shift) in an ordinal logistic regression analysis of the primary outcome. The treatment effect will also be assessed in all patients with ICH who are recruited during each treatment study period. HeadPoST is a large international clinical trial in

Study Protocol. IDUS -- Instrumental delivery & ultrasound. A multi-centre randomised controlled trial of ultrasound assessment of the fetal head position versus standard care as an approach to prevent morbidity at instrumental delivery

LENUS (Irish Health Repository)

Murphy, Deirdre J

2012-09-13

AbstractBackgroundInstrumental deliveries are commonly performed in the United Kingdom and Ireland, with rates of 12 – 17% in most centres. Knowing the exact position of the fetal head is a pre-requisite for safe instrumental delivery. Traditionally, diagnosis of the fetal head position is made on transvaginal digital examination by delineating the suture lines of the fetal skull and the fontanelles. However, the accuracy of transvaginal digital examination can be unreliable and varies between 20% and 75%. Failure to identify the correct fetal head position increases the likelihood of failed instrumental delivery with the additional morbidity of sequential use of instruments or second stage caesarean section. The use of ultrasound in determining the position of the fetal head has been explored but is not part of routine clinical practice.Methods\\/DesignA multi-centre randomised controlled trial is proposed. The study will take place in two large maternity units in Ireland with a combined annual birth rate of 13,500 deliveries. It will involve 450 nulliparous women undergoing instrumental delivery after 37 weeks gestation. The main outcome measure will be incorrect diagnosis of the fetal head position. A study involving 450 women will have 80% power to detect a 10% difference in the incidence of inaccurate diagnosis of the fetal head position with two-sided 5% alpha.DiscussionIt is both important and timely to evaluate the use of ultrasound to diagnose the fetal head position prior to instrumental delivery before routine use can be advocated. The overall aim is to reduce the incidence of incorrect diagnosis of the fetal head position prior to instrumental delivery and improve the safety of instrumental deliveries.Trial registrationCurrent Controlled Trials ISRCTN72230496

Experiences constructing and running large shared clusters at CERN

International Nuclear Information System (INIS)

Bahyl, V.; Barroso, M.; Charbonnier, C.; Eldik, J. van; Jones, P.; Kleinwort, T.; Smith, T.

2001-01-01

The latest steps in the steady evolution of the CERN Computer Centre have been to reduce the multitude of clusters and architectures and to concentrate on commodity hardware. An active RISC decommissioning program has been undertaken to encourage migration to Linux, and a program of merging dedicated experiment clusters into larger shared facilities has been launched. The authors describe these programs and the experiences running the resultant multi-hundred node shared Linux clusters

Task shifting of frontline community health workers for cardiovascular risk reduction: design and rationale of a cluster randomised controlled trial (DISHA study) in India.

Science.gov (United States)

Jeemon, Panniyammakal; Narayanan, Gitanjali; Kondal, Dimple; Kahol, Kashvi; Bharadwaj, Ashok; Purty, Anil; Negi, Prakash; Ladhani, Sulaiman; Sanghvi, Jyoti; Singh, Kuldeep; Kapoor, Deksha; Sobti, Nidhi; Lall, Dorothy; Manimunda, Sathyaprakash; Dwivedi, Supriya; Toteja, Gurudyal; Prabhakaran, Dorairaj

2016-03-15

Effective task-shifting interventions targeted at reducing the global cardiovascular disease (CVD) epidemic in low and middle-income countries (LMICs) are urgently needed. DISHA is a cluster randomised controlled trial conducted across 10 sites (5 in phase 1 and 5 in phase 2) in India in 120 clusters. At each site, 12 clusters were randomly selected from a district. A cluster is defined as a small village with 250-300 households and well defined geographical boundaries. They were then randomly allocated to intervention and control clusters in a 1:1 allocation sequence. If any of the intervention and control clusters were workers (mainly Anganwadi workers and ASHA workers) and a post intervention survey in a representative sample. The study staff had no information on intervention allocation until the completion of the baseline survey. In order to ensure comparability of data across sites, the DISHA study follows a common protocol and manual of operation with standardized measurement techniques. Our study is the largest community based cluster randomised trial in low and middle-income country settings designed to test the effectiveness of 'task shifting' interventions involving frontline health workers for cardiovascular risk reduction. CTRI/2013/10/004049 . Registered 7 October 2013.

Getting better at chronic care in remote communities: study protocol for a pragmatic cluster randomised controlled of community based management

Directory of Open Access Journals (Sweden)

Schmidt Barbara

2012-11-01

Full Text Available Abstract Background Prevalence and incidence of diabetes and other common comorbid conditions (hypertension, coronary heart disease, renal disease and chronic lung disease are extremely high among Indigenous Australians. Recent measures to improve quality of preventive care in Indigenous community settings, while apparently successful at increasing screening and routine check-up rates, have shown only modest or little improvements in appropriate care such as the introduction of insulin and other scaled-up drug regimens in line with evidence-based guidelines, together with support for risk factor reduction. A new strategy is required to ensure high quality integrated family-centred care is available locally, with continuity and cultural safety, by community-based care coordinators with appropriate system supports. Methods/design The trial design is open parallel cluster randomised controlled trial. The objective of this pragmatic trial is to test the effectiveness of a model of health service delivery that facilitates integrated community-based, intensive chronic condition management, compared with usual care, in rural and remote Indigenous primary health care services in north Queensland. Participants are Indigenous adults (aged 18–65 years with poorly controlled diabetes (HbA1c>=8.5 and at least one other chronic condition. The intervention is to employ an Indigenous Health Worker to case manage the care of a maximum caseload of 30 participants. The Indigenous Health Workers receive intensive clinical training initially, and throughout the study, to ensure they are competent to coordinate care for people with chronic conditions. The Indigenous Health Workers, supported by the local primary health care (PHC team and an Indigenous Clinical Support Team, will manage care, including coordinating access to multidisciplinary team care based on best practice standards. Allocation by cluster to the intervention and control groups is by simple

Authorship issues in multi-centre clinical trials: the importance of making an authorship contract.

Science.gov (United States)

Rosenberg, Jacob; Burcharth, Jakob; Pommergaard, Hans-Christian; Vinther, Siri

2015-02-01

Discussions about authorship often arise in multi-centre clinical trials. Such trials may involve up to hundreds of contributors of whom some will eventually co-author the final publication. It is, however, often impossible to involve all contributors in the manuscript process sufficiently for them to qualify for authorship as defined by the International Committee of Medical Journal Editors. Therefore, rules for authorship in multi-centre trials are strongly recommended. We propose two contracts to prevent conflicts regarding authorship; both are freely available for use without pay but with reference to the original source.

Enhanced performance feedback and patient participation to improve hand hygiene compliance of health-care workers in the setting of established multimodal promotion: a single-centre, cluster randomised controlled trial.

Science.gov (United States)

Stewardson, Andrew James; Sax, Hugo; Gayet-Ageron, Angèle; Touveneau, Sylvie; Longtin, Yves; Zingg, Walter; Pittet, Didier

2016-12-01

Hand hygiene compliance of health-care workers remains suboptimal despite standard multimodal promotion, and evidence for the effectiveness of novel interventions is urgently needed. We aimed to assess the effect of enhanced performance feedback and patient participation on hand hygiene compliance in the setting of multimodal promotion. We did a single-centre, cluster randomised controlled trial at University of Geneva Hospitals (Geneva, Switzerland). All wards hosting adult, lucid patients, and all health-care workers and patients in these wards, were eligible. After a 15-month baseline period, eligible wards were assigned by computer-generated block randomisation (1:1:1), stratified by the type of ward, to one of three groups: control, enhanced performance feedback, or enhanced performance feedback plus patient participation. Standard multimodal hand hygiene promotion was done hospital-wide throughout the study. The primary outcome was hand hygiene compliance of health-care workers (according to the WHO Five Moments of Hand Hygiene) at the opportunity level, measured by direct observation (20-min sessions) by 12 validated infection control nurses, with each ward audited at least once every 3 months. This trial is registered with ISRCTN, number ISRCTN43599478. We randomly assigned 67 wards to the control group (n=21), enhanced performance feedback (n=24), or enhanced performance feedback plus patient participation (n=22) on May 19, 2010. One ward in the control group became a high-dependency unit and was excluded from analysis. During 1367 observation sessions, 12 579 hand hygiene opportunities were recorded. Between the baseline period (April 1, 2009, to June 30, 2010) and the intervention period (July 1, 2010, to June 30, 2012), mean hand hygiene compliance increased from 66% (95% CI 62-70) to 73% (70-77) in the control group (odds ratio [OR] 1·41, 95% CI 1·21-1·63), from 65% (62-69) to 75% (72-77) in the enhanced performance feedback group (1·61, 1·41-1�

Providing NHS staff with height-adjustable workstations and behaviour change strategies to reduce workplace sitting time: protocol for the Stand More AT (SMArT) Work cluster randomised controlled trial.

Science.gov (United States)

O'Connell, S E; Jackson, B R; Edwardson, C L; Yates, T; Biddle, S J H; Davies, M J; Dunstan, D; Esliger, D; Gray, L; Miller, P; Munir, F

2015-12-09

High levels of sedentary behaviour (i.e., sitting) are a risk factor for poor health. With high levels of sitting widespread in desk-based office workers, office workplaces are an appropriate setting for interventions aimed at reducing sedentary behaviour. This paper describes the development processes and proposed intervention procedures of Stand More AT (SMArT) Work, a multi-component randomised control (RCT) trial which aims to reduce occupational sitting time in desk-based office workers within the National Health Service (NHS). SMArT Work consists of 2 phases: 1) intervention development: The development of the SMArT Work intervention takes a community-based participatory research approach using the Behaviour Change Wheel. Focus groups will collect detailed information to gain a better understanding of the most appropriate strategies, to sit alongside the provision of height-adjustable workstations, at the environmental, organisational and individual level that support less occupational sitting. 2) intervention delivery and evaluation: The 12 month cluster RCT aims to reduce workplace sitting in the University Hospitals of Leicester NHS Trust. Desk-based office workers (n = 238) will be randomised to control or intervention clusters, with the intervention group receiving height-adjustable workstations and supporting techniques based on the feedback received from the development phase. Data will be collected at four time points; baseline, 3, 6 and 12 months. The primary outcome is a reduction in sitting time, measured by the activPAL(TM) micro at 12 months. Secondary outcomes include objectively measured physical activity and a variety of work-related health and psycho-social measures. A process evaluation will also take place. This study will be the first long-term, evidence-based, multi-component cluster RCT aimed at reducing occupational sitting within the NHS. This study will help form a better understanding and knowledge base of facilitators and

Design Optimization of Multi-Cluster Embedded Systems for Real-Time Applications

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2004-01-01

We present an approach to design optimization of multi-cluster embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways. In this paper, we address design problems which are characteristic to multi-clusters: partitioning of the system functionality...... into time-triggered and event-triggered domains, process mapping, and the optimization of parameters corresponding to the communication protocol. We present several heuristics for solving these problems. Our heuristics are able to find schedulable implementations under limited resources, achieving...... an efficient utilization of the system. The developed algorithms are evaluated using extensive experiments and a real-life example....

Design Optimization of Multi-Cluster Embedded Systems for Real-Time Applications

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2006-01-01

We present an approach to design optimization of multi-cluster embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways. In this paper, we address design problems which are characteristic to multi-clusters: partitioning of the system functionality...... into time-triggered and event-triggered domains, process mapping, and the optimization of parameters corresponding to the communication protocol. We present several heuristics for solving these problems. Our heuristics are able to find schedulable implementations under limited resources, achieving...... an efficient utilization of the system. The developed algorithms are evaluated using extensive experiments and a real-life example....

Does a pre-hospital emergency pathway improve early diagnosis and referral in suspected stroke patients? – Study protocol of a cluster randomised trial [ISRCTN41456865

Directory of Open Access Journals (Sweden)

Lori Giuliano

2005-10-01

Full Text Available Abstract Background Early interventions proved to be able to improve prognosis in acute stroke patients. Prompt identification of symptoms, organised timely and efficient transportation towards appropriate facilities, become essential part of effective treatment. The implementation of an evidence based pre-hospital stroke care pathway may be a method for achieving the organizational standards required to grant appropriate care. We performed a systematic search for studies evaluating the effect of pre-hospital and emergency interventions for suspected stroke patients and we found that there seems to be only a few studies on the emergency field and none about implementation of clinical pathways. We will test the hypothesis that the adoption of emergency clinical pathway improves early diagnosis and referral in suspected stroke patients. We designed a cluster randomised controlled trial (C-RCT, the most powerful study design to assess the impact of complex interventions. The study was registered in the Current Controlled Trials Register: ISRCTN41456865 – Implementation of pre-hospital emergency pathway for stroke – a cluster randomised trial. Methods/design Two-arm cluster-randomised trial (C-RCT. 16 emergency services and 14 emergency rooms were randomised either to arm 1 (comprising a training module and administration of the guideline, or to arm 2 (no intervention, current practice. Arm 1 participants (152 physicians, 280 nurses, 50 drivers attended an interactive two sessions course with continuous medical education CME credits on the contents of the clinical pathway. We estimated that around 750 patients will be met by the services in the 6 months of observation. This duration allows recruiting a sample of patients sufficient to observe a 30% improvement in the proportion of appropriate diagnoses. Data collection will be performed using current information systems. Process outcomes will be measured at the cluster level six months after the

A pragmatic cluster randomised trial evaluating three implementation interventions

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Rycroft-Malone Jo

2012-08-01

Full Text Available Abstract Background Implementation research is concerned with bridging the gap between evidence and practice through the study of methods to promote the uptake of research into routine practice. Good quality evidence has been summarised into guideline recommendations to show that peri-operative fasting times could be considerably shorter than patients currently experience. The objective of this trial was to evaluate the effectiveness of three strategies for the implementation of recommendations about peri-operative fasting. Methods A pragmatic cluster randomised trial underpinned by the PARIHS framework was conducted during 2006 to 2009 with a national sample of UK hospitals using time series with mixed methods process evaluation and cost analysis. Hospitals were randomised to one of three interventions: standard dissemination (SD of a guideline package, SD plus a web-based resource championed by an opinion leader, and SD plus plan-do-study-act (PDSA. The primary outcome was duration of fluid fast prior to induction of anaesthesia. Secondary outcomes included duration of food fast, patients’ experiences, and stakeholders’ experiences of implementation, including influences. ANOVA was used to test differences over time and interventions. Results Nineteen acute NHS hospitals participated. Across timepoints, 3,505 duration of fasting observations were recorded. No significant effect of the interventions was observed for either fluid or food fasting times. The effect size was 0.33 for the web-based intervention compared to SD alone for the change in fluid fasting and was 0.12 for PDSA compared to SD alone. The process evaluation showed different types of impact, including changes to practices, policies, and attitudes. A rich picture of the implementation challenges emerged, including inter-professional tensions and a lack of clarity for decision-making authority and responsibility. Conclusions This was a large, complex study and one of the first

Disrupted globular clusters and the gamma-ray excess in the Galactic Centre

Science.gov (United States)

Fragione, Giacomo; Antonini, Fabio; Gnedin, Oleg Y.

2018-04-01

The Fermi Large Area Telescope has provided the most detailed view towards the Galactic Centre (GC) in high-energy gamma-rays. Besides the interstellar emission and point source contributions, the data suggest a residual diffuse gamma-ray excess. The similarity of its spatial distribution with the expected profile of dark matter has led to claims that this may be evidence for dark matter particle annihilation. Here, we investigate an alternative explanation that the signal originates from millisecond pulsars (MSPs) formed in dense globular clusters and deposited at the GC as a consequence of cluster inspiral and tidal disruption. We use a semi-analytical model to calculate the formation, migration, and disruption of globular clusters in the Galaxy. Our model reproduces the mass of the nuclear star cluster and the present-day radial and mass distribution of globular clusters. For the first time, we calculate the evolution of MSPs from disrupted globular clusters throughout the age of the Galaxy and consistently include the effect of the MSP spin-down due to magnetic-dipole braking. The final gamma-ray amplitude and spatial distribution are in good agreement with the Fermi observations and provide a natural astrophysical explanation for the GC excess.

Cluster-based analysis of multi-model climate ensembles

Science.gov (United States)

Hyde, Richard; Hossaini, Ryan; Leeson, Amber A.

2018-06-01

Clustering - the automated grouping of similar data - can provide powerful and unique insight into large and complex data sets, in a fast and computationally efficient manner. While clustering has been used in a variety of fields (from medical image processing to economics), its application within atmospheric science has been fairly limited to date, and the potential benefits of the application of advanced clustering techniques to climate data (both model output and observations) has yet to be fully realised. In this paper, we explore the specific application of clustering to a multi-model climate ensemble. We hypothesise that clustering techniques can provide (a) a flexible, data-driven method of testing model-observation agreement and (b) a mechanism with which to identify model development priorities. We focus our analysis on chemistry-climate model (CCM) output of tropospheric ozone - an important greenhouse gas - from the recent Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). Tropospheric column ozone from the ACCMIP ensemble was clustered using the Data Density based Clustering (DDC) algorithm. We find that a multi-model mean (MMM) calculated using members of the most-populous cluster identified at each location offers a reduction of up to ˜ 20 % in the global absolute mean bias between the MMM and an observed satellite-based tropospheric ozone climatology, with respect to a simple, all-model MMM. On a spatial basis, the bias is reduced at ˜ 62 % of all locations, with the largest bias reductions occurring in the Northern Hemisphere - where ozone concentrations are relatively large. However, the bias is unchanged at 9 % of all locations and increases at 29 %, particularly in the Southern Hemisphere. The latter demonstrates that although cluster-based subsampling acts to remove outlier model data, such data may in fact be closer to observed values in some locations. We further demonstrate that clustering can provide a viable and

Study Protocol. IDUS – Instrumental delivery & ultrasound. A multi-centre randomised controlled trial of ultrasound assessment of the fetal head position versus standard care as an approach to prevent morbidity at instrumental delivery

Directory of Open Access Journals (Sweden)

Murphy Deirdre J

2012-09-01

Full Text Available Abstract Background Instrumental deliveries are commonly performed in the United Kingdom and Ireland, with rates of 12 – 17% in most centres. Knowing the exact position of the fetal head is a pre-requisite for safe instrumental delivery. Traditionally, diagnosis of the fetal head position is made on transvaginal digital examination by delineating the suture lines of the fetal skull and the fontanelles. However, the accuracy of transvaginal digital examination can be unreliable and varies between 20% and 75%. Failure to identify the correct fetal head position increases the likelihood of failed instrumental delivery with the additional morbidity of sequential use of instruments or second stage caesarean section. The use of ultrasound in determining the position of the fetal head has been explored but is not part of routine clinical practice. Methods/Design A multi-centre randomised controlled trial is proposed. The study will take place in two large maternity units in Ireland with a combined annual birth rate of 13,500 deliveries. It will involve 450 nulliparous women undergoing instrumental delivery after 37 weeks gestation. The main outcome measure will be incorrect diagnosis of the fetal head position. A study involving 450 women will have 80% power to detect a 10% difference in the incidence of inaccurate diagnosis of the fetal head position with two-sided 5% alpha. Discussion It is both important and timely to evaluate the use of ultrasound to diagnose the fetal head position prior to instrumental delivery before routine use can be advocated. The overall aim is to reduce the incidence of incorrect diagnosis of the fetal head position prior to instrumental delivery and improve the safety of instrumental deliveries. Trial registration Current Controlled Trials ISRCTN72230496

Child Centred Approach to Climate Change and Health Adaptation through Schools in Bangladesh: A Cluster Randomised Intervention Trial.

Science.gov (United States)

Kabir, Md Iqbal; Rahman, Md Bayzidur; Smith, Wayne; Lusha, Mirza Afreen Fatima; Milton, Abul Hasnat

2015-01-01

Bangladesh is one of the most vulnerable countries to climate change. People are getting educated at different levels on how to deal with potential impacts. One such educational mode was the preparation of a school manual, for high school students on climate change and health protection endorsed by the National Curriculum and Textbook Board, which is based on a 2008 World Health Organization manual. The objective of this study was to test the effectiveness of the manual in increasing the knowledge level of the school children about climate change and health adaptation. This cluster randomized intervention trial involved 60 schools throughout Bangladesh, with 3293 secondary school students participating. School upazilas (sub-districts) were randomised into intervention and control groups, and two schools from each upazila were randomly selected. All year seven students from both groups of schools sat for a pre-test of 30 short questions of binary response. A total of 1515 students from 30 intervention schools received the intervention through classroom training based on the school manual and 1778 students of the 30 control schools did not get the manual but a leaflet on climate change and health issues. Six months later, a post-intervention test of the same questionnaire used in the pre-test was performed at both intervention and control schools. The pre and post test scores were analysed along with the demographic data by using random effects model. None of the various school level and student level variables were significantly different between the control and intervention group. However, the intervention group had a 17.42% (95% CI: 14.45 to 20.38, P = school-based intervention for climate change and health adaptation is effective for increasing the knowledge level of school children on this topic.

Child Centred Approach to Climate Change and Health Adaptation through Schools in Bangladesh: A Cluster Randomised Intervention Trial

Science.gov (United States)

Kabir, Md Iqbal; Rahman, Md Bayzidur; Smith, Wayne; Lusha, Mirza Afreen Fatima; Milton, Abul Hasnat

2015-01-01

Background Bangladesh is one of the most vulnerable countries to climate change. People are getting educated at different levels on how to deal with potential impacts. One such educational mode was the preparation of a school manual, for high school students on climate change and health protection endorsed by the National Curriculum and Textbook Board, which is based on a 2008 World Health Organization manual. The objective of this study was to test the effectiveness of the manual in increasing the knowledge level of the school children about climate change and health adaptation. Methods This cluster randomized intervention trial involved 60 schools throughout Bangladesh, with 3293 secondary school students participating. School upazilas (sub-districts) were randomised into intervention and control groups, and two schools from each upazila were randomly selected. All year seven students from both groups of schools sat for a pre-test of 30 short questions of binary response. A total of 1515 students from 30 intervention schools received the intervention through classroom training based on the school manual and 1778 students of the 30 control schools did not get the manual but a leaflet on climate change and health issues. Six months later, a post-intervention test of the same questionnaire used in the pre-test was performed at both intervention and control schools. The pre and post test scores were analysed along with the demographic data by using random effects model. Results None of the various school level and student level variables were significantly different between the control and intervention group. However, the intervention group had a 17.42% (95% CI: 14.45 to 20.38, P = school-based intervention for climate change and health adaptation is effective for increasing the knowledge level of school children on this topic. PMID:26252381

A multifaceted strategy using mobile technology to assist rural primary healthcare doctors and frontline health workers in cardiovascular disease risk management: protocol for the SMARTHealth India cluster randomised controlled trial.

Science.gov (United States)

Praveen, Devarsetty; Patel, Anushka; McMahon, Stephen; Prabhakaran, Dorairaj; Clifford, Gari D; Maulik, Pallab K; Joshi, Rohina; Jan, Stephen; Heritier, Stephane; Peiris, David

2013-11-25

Blood Pressure related disease affected 118 million people in India in the year 2000; this figure will double by 2025. Around one in four adults in rural India have hypertension, and of those, only a minority are accessing appropriate care. Health systems in India face substantial challenges to meet these gaps in care, and innovative solutions are needed. We hypothesise that a multifaceted intervention involving capacity strengthening of primary healthcare doctors and non-physician healthcare workers through use of a mobile device-based clinical decision support system will result in improved blood pressure control for individuals at high risk of a cardiovascular disease event when compared with usual healthcare. This intervention will be implemented as a stepped wedge, cluster randomised controlled trial in 18 primary health centres and 54 villages in rural Andhra Pradesh involving adults aged ≥40 years at high cardiovascular disease event risk (approximately 15,000 people). Cardiovascular disease event risk will be calculated based on World Health Organisation/International Society of Hypertension's region-specific risk charts. Cluster randomisation will occur at the level of the primary health centres. Outcome analyses will be conducted blinded to intervention allocation. The primary study outcome is the difference in the proportion of people meeting guideline-recommended blood pressure targets in the intervention period vs. the control period. Secondary outcomes include mean reduction in blood pressure levels; change in other cardiovascular disease risk factors, including body mass index, current smoking, reported healthy eating habits, and reported physical activity levels; self-reported use of blood pressure and other cardiovascular medicines; quality of life (using the EQ-5D); and cardiovascular disease events (using hospitalisation data). Trial outcomes will be accompanied by detailed process and economic evaluations. The findings are likely to inform

Effectiveness of the HuCare Quality Improvement Strategy on health-related quality of life in patients with cancer: study protocol of a stepped-wedge cluster randomised controlled trial (HuCare2 study).

Science.gov (United States)

Caminiti, Caterina; Iezzi, Elisa; Passalacqua, Rodolfo

2017-10-06

Our group previously demonstrated the feasibility of the HuCare Quality Improvement Strategy (HQIS), aimed at integrating into practice six psychosocial interventions recommended by international guidelines. This trial will assess whether the introduction of the strategy in oncology wards improves patient's health-related quality of life (HRQoL). Multicentre, incomplete stepped-wedge cluster randomised controlled trial, conducted in three clusters of five centres each, in three equally spaced time epochs. The study also includes an initial epoch when none of the centres are exposed to the intervention, and a final epoch when all centres will have implemented the strategy. The intervention is applied at a cluster level, and assessed at an individual level with cross-sectional model. A total of 720 patients who received a cancer diagnosis in the previous 2 months and about to start medical treatment will be enrolled. The primary aim is to evaluate the effectiveness of the HQIS versus standard care in terms of improvement of at least one of two domains (emotional and social functions) of HRQoL using the EORTC QLQ-C30 (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 items) questionnaire, at baseline and at 3 months. This outcome was chosen because patients with cancer generally exhibit low HRQoL, particularly at certain stages of care, and because it allows to assess the strategy's impact as perceived by patients themselves. The HQIS comprises three phases: (1) clinician training-to improve communication-relational skills and instruct on the project; (2) centre support-four on-site visits by experts of the project team, aimed to boost motivation, help with context analysis and identification of solutions; (3) implementation of Evidence-Based Medicine (EBM) recommendations at the centre. Ethics committee review approval has been obtained from the Ethics Committee of Parma. Results will be disseminated at conferences, and

Penalized likelihood and multi-objective spatial scans for the detection and inference of irregular clusters

Directory of Open Access Journals (Sweden)

Fonseca Carlos M

2010-10-01

Full Text Available Abstract Background Irregularly shaped spatial clusters are difficult to delineate. A cluster found by an algorithm often spreads through large portions of the map, impacting its geographical meaning. Penalized likelihood methods for Kulldorff's spatial scan statistics have been used to control the excessive freedom of the shape of clusters. Penalty functions based on cluster geometry and non-connectivity have been proposed recently. Another approach involves the use of a multi-objective algorithm to maximize two objectives: the spatial scan statistics and the geometric penalty function. Results & Discussion We present a novel scan statistic algorithm employing a function based on the graph topology to penalize the presence of under-populated disconnection nodes in candidate clusters, the disconnection nodes cohesion function. A disconnection node is defined as a region within a cluster, such that its removal disconnects the cluster. By applying this function, the most geographically meaningful clusters are sifted through the immense set of possible irregularly shaped candidate cluster solutions. To evaluate the statistical significance of solutions for multi-objective scans, a statistical approach based on the concept of attainment function is used. In this paper we compared different penalized likelihoods employing the geometric and non-connectivity regularity functions and the novel disconnection nodes cohesion function. We also build multi-objective scans using those three functions and compare them with the previous penalized likelihood scans. An application is presented using comprehensive state-wide data for Chagas' disease in puerperal women in Minas Gerais state, Brazil. Conclusions We show that, compared to the other single-objective algorithms, multi-objective scans present better performance, regarding power, sensitivity and positive predicted value. The multi-objective non-connectivity scan is faster and better suited for the

Dense Clustered Multi-Channel Wireless Sensor Cloud

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Sivaramakrishnan Sivakumar

2015-08-01

Full Text Available Dense Wireless Sensor Network Clouds have an inherent issue of latency and packet drops with regards to data collection. Though there is extensive literature that tries to address these issues through either scheduling, channel contention or a combination of the two, the problem still largely exists. In this paper, a Clustered Multi-Channel Scheduling Protocol (CMSP is designed that creates a Voronoi partition of a dense network. Each partition is assigned a channel, and a scheduling scheme is adopted to collect data within the Voronoi partitions. This scheme collects data from the partitions concurrently and then passes it to the base station. CMSP is compared using simulation with other multi-channel protocols like Tree-based Multi-Channel, Multi-Channel MAC and Multi-frequency Media Access Control for wireless sensor networks. Results indicate CMSP has higher throughput and data delivery ratio at a lower power consumption due to network partitioning and hierarchical scheduling that minimizes load on the network.

Return-to-work intervention versus usual care for sick-listed employees : Health-economic investment appraisal alongside a cluster randomised trial

NARCIS (Netherlands)

Lokman, S.; Volker, D.; Zijlstra-Vlasveld, M.C.; Brouwers, E.P.M.; Boon, B.; Beekman, A.T.; Smit, F.; van der Feltz-Cornelis, C.M.

2017-01-01

To evaluate the health-economic costs and benefits of a guided eHealth intervention (E-health module embedded in Collaborative Occupational healthcare (ECO)) encouraging sick-listed employees to a faster return to work. A two-armed cluster randomised trial with occupational physicians (OPs) (n=62),

A pragmatic randomised multi-centre trial of multifamily and single family therapy for adolescent anorexia nervosa.

Science.gov (United States)

Eisler, Ivan; Simic, Mima; Hodsoll, John; Asen, Eia; Berelowitz, Mark; Connan, Frances; Ellis, Gladys; Hugo, Pippa; Schmidt, Ulrike; Treasure, Janet; Yi, Irene; Landau, Sabine

2016-11-24

Considerable progress has been made in recent years in developing effective treatments for child and adolescent anorexia nervosa, with a general consensus in the field that eating disorders focussed family therapy (often referred to as Maudsley Family Therapy or Family Based Treatment) currently offers the most promising outcomes. Nevertheless, a significant number do not respond well and additional treatment developments are needed to improve outcomes. Multifamily therapy is a promising treatment that has attracted considerable interest and we report the results of the first randomised controlled trial of multifamily therapy for adolescent anorexia nervosa. The study was a pragmatic multicentre randomised controlled superiority trial comparing two outpatient eating disorder focussed family interventions - multifamily therapy (MFT-AN) and single family therapy (FT-AN). A total of 169 adolescents with a DSM-IV diagnosis of anorexia nervosa or eating disorder not otherwise specified (restricting type) were randomised to the two treatments using computer generated blocks of random sizes to ensure balanced numbers in the trial arms. Independent assessors, blind to the allocation, completed evaluations at baseline, 3 months, 12 months (end of treatment) and 18 months. Both treatment groups showed clinically significant improvements with just under 60% achieving a good or intermediate outcome (on the Morgan-Russell scales) at the end of treatment in the FT-AN group and more than 75% in the MFT-AN group - a statistically significant benefit in favour of the multifamily intervention (OR = 2.55 95%; CI 1.17, 5.52; p = 0.019). At follow-up (18 months post baseline) there was relatively little change compared to end of treatment although the difference in primary outcome between the treatments was no longer statistically significant. Clinically significant gains in weight were accompanied by improvements in mood and eating disorder psychopathology. Approximately

Cluster Randomised Trials in Cochrane Reviews: Evaluation of Methodological and Reporting Practice.

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Marty Richardson

Full Text Available Systematic reviews can include cluster-randomised controlled trials (C-RCTs, which require different analysis compared with standard individual-randomised controlled trials. However, it is not known whether review authors follow the methodological and reporting guidance when including these trials. The aim of this study was to assess the methodological and reporting practice of Cochrane reviews that included C-RCTs against criteria developed from existing guidance.Criteria were developed, based on methodological literature and personal experience supervising review production and quality. Criteria were grouped into four themes: identifying, reporting, assessing risk of bias, and analysing C-RCTs. The Cochrane Database of Systematic Reviews was searched (2nd December 2013, and the 50 most recent reviews that included C-RCTs were retrieved. Each review was then assessed using the criteria.The 50 reviews we identified were published by 26 Cochrane Review Groups between June 2013 and November 2013. For identifying C-RCTs, only 56% identified that C-RCTs were eligible for inclusion in the review in the eligibility criteria. For reporting C-RCTs, only eight (24% of the 33 reviews reported the method of cluster adjustment for their included C-RCTs. For assessing risk of bias, only one review assessed all five C-RCT-specific risk-of-bias criteria. For analysing C-RCTs, of the 27 reviews that presented unadjusted data, only nine (33% provided a warning that confidence intervals may be artificially narrow. Of the 34 reviews that reported data from unadjusted C-RCTs, only 13 (38% excluded the unadjusted results from the meta-analyses.The methodological and reporting practices in Cochrane reviews incorporating C-RCTs could be greatly improved, particularly with regard to analyses. Criteria developed as part of the current study could be used by review authors or editors to identify errors and improve the quality of published systematic reviews incorporating

Cost and cost-effectiveness of newborn home visits: findings from the Newhints cluster-randomised controlled trial in rural Ghana

NARCIS (Netherlands)

Pitt, Catherine; Tawiah, Theresa; Soremekun, Seyi; ten Asbroek, Augustinus H. A.; Manu, Alexander; Tawiah-Agyemang, Charlotte; Hill, Zelee; Owusu-Agyei, Seth; Kirkwood, Betty R.; Hanson, Kara

2016-01-01

Every year, 2·9 million newborn babies die worldwide. A meta-analysis of four cluster-randomised controlled trials estimated that home visits by trained community members in programme settings in Ghana and south Asia reduced neonatal mortality by 12% (95% CI 5-18). We aimed to estimate the costs and

Illness management and recovery (IMR) in Danish community mental health centres

DEFF Research Database (Denmark)

Dalum, Helle Stentoft; Korsbek, Lisa; Mikkelsen, John Hagel

2011-01-01

is a randomised, assessor-blinded, multi-centre, clinical trial of the IMR program compared with treatment as usual for 200 participants diagnosed with schizophrenia or bipolar disorder under the care of two community mental health centres in the Capital Region of Denmark. The primary outcome is level......Background: Schizophrenia and bipolar disorder are severe mental illnesses that can have a significant disabling impact on the lives of people. Psychosocial interventions that stress hope and recovery as a part of a multidimensional approach are possibly indicated to support people with severe...... mental illness in facilitating recovery. Illness Management and Recovery (IMR) is a curriculum-based psychosocial intervention designed as structured program with a recovery-oriented approach. The aim of IMR is to rehabilitate people with severe mental illnesses by helping them acquire knowledge...

Supplemental parenteral nutrition in critically ill patients: a study protocol for a phase II randomised controlled trial.

Science.gov (United States)

Ridley, Emma J; Davies, Andrew R; Parke, Rachael; Bailey, Michael; McArthur, Colin; Gillanders, Lyn; Cooper, David J; McGuinness, Shay

2015-12-24

Nutrition is one of the fundamentals of care provided to critically ill adults. The volume of enteral nutrition received, however, is often much less than prescribed due to multiple functional and process issues. To deliver the prescribed volume and correct the energy deficit associated with enteral nutrition alone, parenteral nutrition can be used in combination (termed "supplemental parenteral nutrition"), but benefits of this method have not been firmly established. A multi-centre, randomised, clinical trial is currently underway to determine if prescribed energy requirements can be provided to critically ill patients by using a supplemental parenteral nutrition strategy in the critically ill. This prospective, multi-centre, randomised, stratified, parallel-group, controlled, phase II trial aims to determine whether a supplemental parenteral nutrition strategy will reliably and safely increase energy intake when compared to usual care. The study will be conducted for 100 critically ill adults with at least one organ system failure and evidence of insufficient enteral intake from six intensive care units in Australia and New Zealand. Enrolled patients will be allocated to either a supplemental parenteral nutrition strategy for 7 days post randomisation or to usual care with enteral nutrition. The primary outcome will be the average energy amount delivered from nutrition therapy over the first 7 days of the study period. Secondary outcomes include protein delivery for 7 days post randomisation; total energy and protein delivery, antibiotic use and organ failure rates (up to 28 days); duration of ventilation, length of intensive care unit and hospital stay. At both intensive care unit and hospital discharge strength and health-related quality of life assessments will be undertaken. Study participants will be followed up for health-related quality of life, resource utilisation and survival at 90 and 180 days post randomisation (unless death occurs first). This trial

A highly efficient multi-core algorithm for clustering extremely large datasets

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Kraus Johann M

2010-04-01

Full Text Available Abstract Background In recent years, the demand for computational power in computational biology has increased due to rapidly growing data sets from microarray and other high-throughput technologies. This demand is likely to increase. Standard algorithms for analyzing data, such as cluster algorithms, need to be parallelized for fast processing. Unfortunately, most approaches for parallelizing algorithms largely rely on network communication protocols connecting and requiring multiple computers. One answer to this problem is to utilize the intrinsic capabilities in current multi-core hardware to distribute the tasks among the different cores of one computer. Results We introduce a multi-core parallelization of the k-means and k-modes cluster algorithms based on the design principles of transactional memory for clustering gene expression microarray type data and categorial SNP data. Our new shared memory parallel algorithms show to be highly efficient. We demonstrate their computational power and show their utility in cluster stability and sensitivity analysis employing repeated runs with slightly changed parameters. Computation speed of our Java based algorithm was increased by a factor of 10 for large data sets while preserving computational accuracy compared to single-core implementations and a recently published network based parallelization. Conclusions Most desktop computers and even notebooks provide at least dual-core processors. Our multi-core algorithms show that using modern algorithmic concepts, parallelization makes it possible to perform even such laborious tasks as cluster sensitivity and cluster number estimation on the laboratory computer.

Clustering of European winter storms: A multi-model perspective

Science.gov (United States)

Renggli, Dominik; Buettner, Annemarie; Scherb, Anke; Straub, Daniel; Zimmerli, Peter

2016-04-01

The storm series over Europe in 1990 (Daria, Vivian, Wiebke, Herta) and 1999 (Anatol, Lothar, Martin) are very well known. Such clusters of severe events strongly affect the seasonally accumulated damage statistics. The (re)insurance industry has quantified clustering by using distribution assumptions deduced from the historical storm activity of the last 30 to 40 years. The use of storm series simulated by climate models has only started recently. Climate model runs can potentially represent 100s to 1000s of years, allowing a more detailed quantification of clustering than the history of the last few decades. However, it is unknown how sensitive the representation of clustering is to systematic biases. Using a multi-model ensemble allows quantifying that uncertainty. This work uses CMIP5 decadal ensemble hindcasts to study clustering of European winter storms from a multi-model perspective. An objective identification algorithm extracts winter storms (September to April) in the gridded 6-hourly wind data. Since the skill of European storm predictions is very limited on the decadal scale, the different hindcast runs are interpreted as independent realizations. As a consequence, the available hindcast ensemble represents several 1000 simulated storm seasons. The seasonal clustering of winter storms is quantified using the dispersion coefficient. The benchmark for the decadal prediction models is the 20th Century Reanalysis. The decadal prediction models are able to reproduce typical features of the clustering characteristics observed in the reanalysis data. Clustering occurs in all analyzed models over the North Atlantic and European region, in particular over Great Britain and Scandinavia as well as over Iberia (i.e. the exit regions of the North Atlantic storm track). Clustering is generally weaker in the models compared to reanalysis, although the differences between different models are substantial. In contrast to existing studies, clustering is driven by weak

Study protocol: The development of a pilot study employing a randomised controlled design to investigate the feasibility and effects of a peer support program following discharge from a specialist first-episode psychosis treatment centre

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Francey Shona

2010-05-01

Full Text Available Abstract Background Young people with first-episode psychosis (FEP are at risk of a range of negative outcomes. Specialist FEP services have been developed to provide comprehensive, multi-disciplinary treatment. However, these services are often available for a restricted period and the services that young people may be transferred to are less comprehensive. This represents a risk of drop out from treatment services in a group already considered to be at risk of disengagement. Peer support groups have been shown to improve social relationships among people with psychosis however individual peer support programs have not been tested on young people with first-episode psychosis; nor have they been tested at the point of discharge from services. Methods/design The study is an 18-month randomised controlled trial being conducted at Orygen Youth Health Research Centre in Melbourne, Australia. The aim of the study is to test the feasibility and effects of a 6-month peer support intervention delivered to young people with FEP over the period of discharge. Participants are young people aged 15-24 who are being discharged from a specialist first-episode psychosis treatment centre. There is a 6-month recruitment period. The intervention comprises two hours of contact per fortnight during which peer support workers can assist participants to engage with their new services, or other social and community activities. Participants will be assessed at baseline and post intervention (6 months. Discussion This paper describes the development of a randomised-controlled trial which aims to pilot a peer support program among young people who are being discharged from a specialist FEP treatment centre. If effective, the intervention could lead to benefits not only for participants over the discharge period, but for peer support workers as well. Trial registration The study was registered with the Australian New Zealand Clinical Trials Registry; number: ACTRN

Protocol for a Cluster Randomised Controlled Trial to Compare the “Taste & See” Programme—A Church-Based Programme to Develop a Healthy Relationship with Food—With a Wait-List Control

Directory of Open Access Journals (Sweden)

Deborah Lycett

2018-03-01

Full Text Available (1 Background: Obesity is strongly associated with poor mental-health. Spiritual and religious wellbeing is associated with improved mental well-being and reduced emotional eating. “Taste & See”, a church based programme to help develop a healthy relationship with food has been successfully tested for feasibility in the UK but an adequately powered randomised controlled trial is needed to test efficacy. This paper reports on the protocol for such a trial; (2 Method: A cluster, randomised controlled trial where Christian churches (any denomination are the unit of randomisation. 150 overweight adults will be recruited from approximately 15 churches (clusters in the UK, each church (cluster will recruit approximately 10 participants. Churches will be randomised 2:1 to either begin the “Taste & See” programme immediately or in 10 weeks’ time. Data on eating habits, mental and spiritual health will be collected online before and after the intervention and control period and follow-up will continue until 2 years; (3 Implication of Results: Should the programme prove effective it will provide strong clinical evidence of the role of churches in improving the health and well-being of those struggling with food and weight issues.

Schedulability-Driven Partitioning and Mapping for Multi-Cluster Real-Time Systems

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2004-01-01

We present an approach to partitioning and mapping for multi-cluster embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways. We have proposed a schedulability analysis for such systems, including a worst-case queuing delay analysis for the gateways...

Proposal for the standardisation of multi-centre trials in nuclear medicine imaging

DEFF Research Database (Denmark)

Dickson, John Caddell; Tossici-Bolt, Livia; Sera, Terez

2012-01-01

Multi-centre trials are an important part of proving the efficacy of procedures, drugs and interventions. Imaging components in such trials are becoming increasingly common; however, without sufficient control measures the usefulness of these data can be compromised. This paper describes a framew...

Scandcleft randomised trials of primary surgery for unilateral cleft lip and palate

DEFF Research Database (Denmark)

Heliövaara, Arja; Küseler, Annelise; Skaare, Pål

2017-01-01

BACKGROUND AND AIM: Good dentofacial growth is a major goal in the treatment of unilateral cleft lip and palate (UCLP). The aim was to evaluate dental arch relationships at age 5 years after four different protocols of primary surgery for UCLP. DESIGN: Three parallel randomised clinical trials were...... undertaken as an international multi-centre study by 10 cleft teams in five countries: Denmark, Finland, Sweden, Norway, and the UK. METHODS: Three different surgical procedures for primary palatal repair (Arms B, C, D) were tested against a common procedure (Arm A) in the total cohort of 448 children born...

A randomised controlled trial of oxytocin 5IU and placebo infusion versus oxytocin 5IU and 30IU infusion for the control of blood loss at elective caesarean section--pilot study. ISRCTN 40302163.

LENUS (Irish Health Repository)

Murphy, Deirdre J

2012-02-01

OBJECTIVE: To compare the blood loss at elective lower segment caesarean section with administration of oxytocin 5IU bolus versus oxytocin 5IU bolus and oxytocin 30IU infusion and to establish whether a large multi-centre trial is feasible. STUDY DESIGN: Women booked for an elective caesarean section were recruited to a pilot randomised controlled trial and randomised to either oxytocin 5IU bolus and placebo infusion or oxytocin 5IU bolus and oxytocin 30IU infusion. We wished to establish whether the study design was feasible and acceptable and to establish sample size estimates for a definitive multi-centre trial. The outcome measures were total estimated blood loss at caesarean section and in the immediate postpartum period and the need for an additional uterotonic agent. RESULTS: A total of 115 women were randomised and 110 were suitable for analysis (5 protocol violations). Despite strict exclusion criteria 84% of the target population were considered eligible for study participation and of those approached only 15% declined to participate and 11% delivered prior to the planned date. The total mean estimated blood loss was lower in the oxytocin infusion arm compared to placebo (567 ml versus 624 ml) and fewer women had a major haemorrhage (>1000 ml, 14% versus 17%) or required an additional uterotonic agent (5% versus 11%). A sample size of 1500 in each arm would be required to demonstrate a 3% absolute reduction in major haemorrhage (from baseline 10%) with >80% power. CONCLUSION: An additional oxytocin infusion at elective caesarean section may reduce blood loss and warrants evaluation in a large multi-centre trial.

AN EFFECTIVE MULTI-CLUSTERING ANONYMIZATION APPROACH USING DISCRETE COMPONENT TASK FOR NON-BINARY HIGH DIMENSIONAL DATA SPACES

Directory of Open Access Journals (Sweden)

L.V. Arun Shalin

2016-01-01

Full Text Available Clustering is a process of grouping elements together, designed in such a way that the elements assigned to similar data points in a cluster are more comparable to each other than the remaining data points in a cluster. During clustering certain difficulties related when dealing with high dimensional data are ubiquitous and abundant. Works concentrated using anonymization method for high dimensional data spaces failed to address the problem related to dimensionality reduction during the inclusion of non-binary databases. In this work we study methods for dimensionality reduction for non-binary database. By analyzing the behavior of dimensionality reduction for non-binary database, results in performance improvement with the help of tag based feature. An effective multi-clustering anonymization approach called Discrete Component Task Specific Multi-Clustering (DCTSM is presented for dimensionality reduction on non-binary database. To start with we present the analysis of attribute in the non-binary database and cluster projection identifies the sparseness degree of dimensions. Additionally with the quantum distribution on multi-cluster dimension, the solution for relevancy of attribute and redundancy on non-binary data spaces is provided resulting in performance improvement on the basis of tag based feature. Multi-clustering tag based feature reduction extracts individual features and are correspondingly replaced by the equivalent feature clusters (i.e. tag clusters. During training, the DCTSM approach uses multi-clusters instead of individual tag features and then during decoding individual features is replaced by corresponding multi-clusters. To measure the effectiveness of the method, experiments are conducted on existing anonymization method for high dimensional data spaces and compared with the DCTSM approach using Statlog German Credit Data Set. Improved tag feature extraction and minimum error rate compared to conventional anonymization

Multi scales based sparse matrix spectral clustering image segmentation

Science.gov (United States)

Liu, Zhongmin; Chen, Zhicai; Li, Zhanming; Hu, Wenjin

2018-04-01

In image segmentation, spectral clustering algorithms have to adopt the appropriate scaling parameter to calculate the similarity matrix between the pixels, which may have a great impact on the clustering result. Moreover, when the number of data instance is large, computational complexity and memory use of the algorithm will greatly increase. To solve these two problems, we proposed a new spectral clustering image segmentation algorithm based on multi scales and sparse matrix. We devised a new feature extraction method at first, then extracted the features of image on different scales, at last, using the feature information to construct sparse similarity matrix which can improve the operation efficiency. Compared with traditional spectral clustering algorithm, image segmentation experimental results show our algorithm have better degree of accuracy and robustness.

Remifentanil-propofol analgo-sedation shortens duration of ventilation and length of ICU stay compared to a conventional regimen: A centre randomised, cross-over, open-label study in the Netherlands

NARCIS (Netherlands)

F.W. Rozendaal (Frans); P.E. Spronk (Peter); F.F. Snellen (Ferdinand); A. Schoen (Adri); A.R.H. van Zanten (Arthur); N.A. Foudraine (Norbert); P.G.H. Mulder (Paul); J. Bakker (Jan)

2009-01-01

textabstractObjective: Compare duration of mechanical ventilation (MV), weaning time, ICU-LOS (ICU-LOS), efficacy and safety of remifentanil-based regimen with conventional sedation and analgesia. Design: Centre randomised, open-label, crossover, 'real-life' study. Setting: 15 Dutch hospitals.

Intrinsic alignment in redMaPPer clusters - II. Radial alignment of satellites towards cluster centres

Science.gov (United States)

Huang, Hung-Jin; Mandelbaum, Rachel; Freeman, Peter E.; Chen, Yen-Chi; Rozo, Eduardo; Rykoff, Eli

2018-03-01

We study the orientations of satellite galaxies in redMaPPer clusters constructed from the Sloan Digital Sky Survey at 0.1 measurement methods (re-Gaussianization, de Vaucouleurs, and isophotal shapes), which trace galaxy light profiles at different radii. The measured SA signal depends on these shape measurement methods. We detect the strongest SA signal in isophotal shapes, followed by de Vaucouleurs shapes. While no net SA signal is detected using re-Gaussianization shapes across the entire sample, the observed SA signal reaches a statistically significant level when limiting to a subsample of higher luminosity satellites. We further investigate the impact of noise, systematics, and real physical isophotal twisting effects in the comparison between the SA signal detected via different shape measurement methods. Unlike previous studies, which only consider the dependence of SA on a few parameters, here we explore a total of 17 galaxy and cluster properties, using a statistical model averaging technique to naturally account for parameter correlations and identify significant SA predictors. We find that the measured SA signal is strongest for satellites with the following characteristics: higher luminosity, smaller distance to the cluster centre, rounder in shape, higher bulge fraction, and distributed preferentially along the major axis directions of their centrals. Finally, we provide physical explanations for the identified dependences and discuss the connection to theories of SA.

Theoretical investigation of molecular hydrogen reactions with active centres in B6H5- and AlB6H5- clusters

International Nuclear Information System (INIS)

Mebel', A.M.; Charkin, O.P.

1991-01-01

Nonempirical calculations of sections of potential surface (PS) along the shortest way of reaction of hydrogen interaction with different active centres in AlB 5 H 5 - cluster were conducted. Mechanisms of reactions of valent-saturated hydrides (BH, AlH) and clusters (B 6 H 5 - , AlB 5 H 5 - ) with molecular hydrogen are correlated. Qualitative model enabling to form an opinion about the presence or the absence of barrier on PS of the shortest way of reactions of breaking σ-bond of H-H type on the active centre of cluster, is suggested. The model is based on analysis of the character of canonical MO reagents and products

How to build and evaluate an integrated health care system for chronic patients: study design of a clustered randomised controlled trial in rural China

Directory of Open Access Journals (Sweden)

Wenxi Tang

2015-03-01

Full Text Available Background: While integrated health care system has been proved an effective way to help improving patient health and system efficiency, the exact behaviour model and motivation approach are not so clear in poor rural areas where health human resources and continuous service provision are urgently needed. To gather solid evidence, we initiated a comprehensive intervention project in Qianjiang District, southwest part of rural China in 2012. And after one-year's pilot, we developed an intervention package of team service, comprehensive pathway and prospective- and performance-based payment system.Methods: To testify the potential influence of payment interventions, we use clustered randomised controlled trial, 60 clusters are grouped into two treatment groups and one control group to compare the time and group differences. Difference-in-differences model and structural equation modelling will be used to analyse the intervention effects and pathway. The outcomes are: quality of care, disease burden, supplier cooperative behaviour and patient utilisation behaviour and system efficiency. Repeated multivariate variance analysis will be used to statistically examine the outcome differences.Discussion: This is the first trial of its kind to prove the effects and efficiency of integrated care. Though we adopted randomised controlled trial to gather the highest rank of evidence, still the fully randomisation was hard to realise in health policy reform experiment. To compensate, the designer should take efforts on control for the potential confounders as much as possible. With this trial, we assume the effects will come from: (1 improvement on the quality of life through risk factors control and lifestyles change on patient's behaviours; (2 improvement on quality of care through continuous care and coordinated supplier behaviours; (3 improvement on the system efficiency through active interaction between suppliers and patients

How to build and evaluate an integrated health care system for chronic patients: study design of a clustered randomised controlled trial in rural China.

Science.gov (United States)

Tang, Wenxi; Sun, Xiaowei; Zhang, Yan; Ye, Ting; Zhang, Liang

2015-01-01

While integrated health care system has been proved an effective way to help improving patient health and system efficiency, the exact behaviour model and motivation approach are not so clear in poor rural areas where health human resources and continuous service provision are urgently needed. To gather solid evidence, we initiated a comprehensive intervention project in Qianjiang District, southwest part of rural China in 2012. And after one-year's pilot, we developed an intervention package of team service, comprehensive pathway and prospective- and performance-based payment system. To testify the potential influence of payment interventions, we use clustered randomised controlled trial, 60 clusters are grouped into two treatment groups and one control group to compare the time and group differences. Difference-in-differences model and structural equation modelling will be used to analyse the intervention effects and pathway. The outcomes are: quality of care, disease burden, supplier cooperative behaviour and patient utilisation behaviour and system efficiency. Repeated multivariate variance analysis will be used to statistically examine the outcome differences. This is the first trial of its kind to prove the effects and efficiency of integrated care. Though we adopted randomised controlled trial to gather the highest rank of evidence, still the fully randomisation was hard to realise in health policy reform experiment. To compensate, the designer should take efforts on control for the potential confounders as much as possible. With this trial, we assume the effects will come from: (1) improvement on the quality of life through risk factors control and lifestyles change on patient's behaviours; (2) improvement on quality of care through continuous care and coordinated supplier behaviours; (3) improvement on the system efficiency through active interaction between suppliers and patients. The integrated care system needs collaborative work from different levels

How to build and evaluate an integrated health care system for chronic patients: study design of a clustered randomised controlled trial in rural China

Directory of Open Access Journals (Sweden)

Wenxi Tang

2015-03-01

Full Text Available Background: While integrated health care system has been proved an effective way to help improving patient health and system efficiency, the exact behaviour model and motivation approach are not so clear in poor rural areas where health human resources and continuous service provision are urgently needed. To gather solid evidence, we initiated a comprehensive intervention project in Qianjiang District, southwest part of rural China in 2012. And after one-year's pilot, we developed an intervention package of team service, comprehensive pathway and prospective- and performance-based payment system. Methods: To testify the potential influence of payment interventions, we use clustered randomised controlled trial, 60 clusters are grouped into two treatment groups and one control group to compare the time and group differences. Difference-in-differences model and structural equation modelling will be used to analyse the intervention effects and pathway. The outcomes are: quality of care, disease burden, supplier cooperative behaviour and patient utilisation behaviour and system efficiency. Repeated multivariate variance analysis will be used to statistically examine the outcome differences. Discussion: This is the first trial of its kind to prove the effects and efficiency of integrated care. Though we adopted randomised controlled trial to gather the highest rank of evidence, still the fully randomisation was hard to realise in health policy reform experiment. To compensate, the designer should take efforts on control for the potential confounders as much as possible. With this trial, we assume the effects will come from: (1 improvement on the quality of life through risk factors control and lifestyles change on patient's behaviours; (2 improvement on quality of care through continuous care and coordinated supplier behaviours; (3 improvement on the system efficiency through active interaction between suppliers and patients. Conclusion

MULTI-LABEL ASRS DATASET CLASSIFICATION USING SEMI-SUPERVISED SUBSPACE CLUSTERING

Data.gov (United States)

National Aeronautics and Space Administration — MULTI-LABEL ASRS DATASET CLASSIFICATION USING SEMI-SUPERVISED SUBSPACE CLUSTERING MOHAMMAD SALIM AHMED, LATIFUR KHAN, NIKUNJ OZA, AND MANDAVA RAJESWARI Abstract....

A community-based cluster randomised trial of safe storage to reduce pesticide self-poisoning in rural Sri Lanka

DEFF Research Database (Denmark)

Pearson, Melissa; Konradsen, Flemming; Gunnell, David

2011-01-01

. One approach to reducing access to pesticides is for households to store pesticides in lockable "safe-storage" containers. However, before this approach can be promoted, evidence is required on its effectiveness and safety. Methods/Design A community-based cluster randomised controlled trial has been...... at the 5% significance level. Secondary outcomes will include the incidence of all pesticide poisoning and total self-harm. Discussion This paper describes a large effectiveness study of a community intervention to reduce the burden of intentional poisoning in rural Sri Lanka. The study builds on a strong...... partnership between provincial health services, local and international researchers, and local communities. We discuss issues in relation to randomisation and contamination, engaging control villages, the intervention, and strategies to improve adherence. Trial Registritation The trial is registered...

Formation Mechanism and Binding Energy for Body-Centred Regular Icosahedral Structure of Li13 Cluster

International Nuclear Information System (INIS)

Liu Weina; Li Ping; Gou Qingquan; Zhao Yanping

2008-01-01

The formation mechanism for the body-centred regular icosahedral structure of Li 13 cluster is proposed. The curve of the total energy versus the separation R between the nucleus at the centre and nuclei at the apexes for this structure of Li 13 has been calculated by using the method of Gou's modified arrangement channel quantum mechanics (MACQM). The result shows that the curve has a minimal energy of -96.951 39 a.u. at R = 5.46a 0 . When R approaches to infinity, the total energy of thirteen lithium atoms has the value of -96.564 38 a.u. So the binding energy of Li 13 with respect to thirteen lithium atoms is 0.387 01 a.u. Therefore the binding energy per atom for Li 13 is 0.029 77 a.u. or 0.810 eV, which is greater than the binding energy per atom of 0.453 eV for Li 2 , 0.494 eV for Li 3 , 0.7878 eV for Li 4 , 0.632 eV for Li 5 , and 0.674 eV for Li 7 calculated by us previously. This means that the Li 13 cluster may be formed stably in a body-centred regular icosahedral structure with a greater binding energy

Increasing physical activity among young children from disadvantaged communities: study protocol of a group randomised controlled effectiveness trial

Directory of Open Access Journals (Sweden)

Rebecca M. Stanley

2016-10-01

Full Text Available Abstract Background Participation in regular physical activity (PA during the early years helps children achieve healthy body weight and can substantially improve motor development, bone health, psychosocial health and cognitive development. Despite common assumptions that young children are naturally active, evidence shows that they are insufficiently active for health and developmental benefits. Exploring strategies to increase physical activity in young children is a public health and research priority. Methods Jump Start is a multi-component, multi-setting PA and gross motor skill intervention for young children aged 3–5 years in disadvantaged areas of New South Wales, Australia. The intervention will be evaluated using a two-arm, parallel group, randomised cluster trial. The Jump Start protocol was based on Social Cognitive Theory and includes five components: a structured gross motor skill lesson (Jump In; unstructured outdoor PA and gross motor skill time (Jump Out; energy breaks (Jump Up; activities connecting movement to learning experiences (Jump Through; and a home-based family component to promote PA and gross motor skill (Jump Home. Early childhood education and care centres will be demographically matched and randomised to Jump Start (intervention or usual practice (comparison group. The intervention group receive Jump Start professional development, program resources, monthly newsletters and ongoing intervention support. Outcomes include change in total PA (accelerometers within centre hours, gross motor skill development (Test of Gross Motor Development-2, weight status (body mass index, bone strength (Sunlight MiniOmni Ultrasound Bone Sonometer, self-regulation (Heads-Toes-Knees-Shoulders, executive function tasks, and proxy-report Temperament and Approaches to learning scales, and educator and parent self-efficacy. Extensive quantitative and qualitative process evaluation and a cost-effectiveness evaluation will be conducted

Increasing physical activity among young children from disadvantaged communities: study protocol of a group randomised controlled effectiveness trial.

Science.gov (United States)

Stanley, Rebecca M; Jones, Rachel A; Cliff, Dylan P; Trost, Stewart G; Berthelsen, Donna; Salmon, Jo; Batterham, Marijka; Eckermann, Simon; Reilly, John J; Brown, Ngiare; Mickle, Karen J; Howard, Steven J; Hinkley, Trina; Janssen, Xanne; Chandler, Paul; Cross, Penny; Gowers, Fay; Okely, Anthony D

2016-10-19

Participation in regular physical activity (PA) during the early years helps children achieve healthy body weight and can substantially improve motor development, bone health, psychosocial health and cognitive development. Despite common assumptions that young children are naturally active, evidence shows that they are insufficiently active for health and developmental benefits. Exploring strategies to increase physical activity in young children is a public health and research priority. Jump Start is a multi-component, multi-setting PA and gross motor skill intervention for young children aged 3-5 years in disadvantaged areas of New South Wales, Australia. The intervention will be evaluated using a two-arm, parallel group, randomised cluster trial. The Jump Start protocol was based on Social Cognitive Theory and includes five components: a structured gross motor skill lesson (Jump In); unstructured outdoor PA and gross motor skill time (Jump Out); energy breaks (Jump Up); activities connecting movement to learning experiences (Jump Through); and a home-based family component to promote PA and gross motor skill (Jump Home). Early childhood education and care centres will be demographically matched and randomised to Jump Start (intervention) or usual practice (comparison) group. The intervention group receive Jump Start professional development, program resources, monthly newsletters and ongoing intervention support. Outcomes include change in total PA (accelerometers) within centre hours, gross motor skill development (Test of Gross Motor Development-2), weight status (body mass index), bone strength (Sunlight MiniOmni Ultrasound Bone Sonometer), self-regulation (Heads-Toes-Knees-Shoulders, executive function tasks, and proxy-report Temperament and Approaches to learning scales), and educator and parent self-efficacy. Extensive quantitative and qualitative process evaluation and a cost-effectiveness evaluation will be conducted. The Jump Start intervention is a

Maternal and child health nurse screening and care for mothers experiencing domestic violence (MOVE): a cluster randomised trial.

Science.gov (United States)

Taft, Angela J; Hooker, Leesa; Humphreys, Cathy; Hegarty, Kelsey; Walter, Ruby; Adams, Catina; Agius, Paul; Small, Rhonda

2015-06-25

Mothers are at risk of domestic violence (DV) and its harmful consequences postpartum. There is no evidence to date for sustainability of DV screening in primary care settings. We aimed to test whether a theory-informed, maternal and child health (MCH) nurse-designed model increased and sustained DV screening, disclosure, safety planning and referrals compared with usual care. Cluster randomised controlled trial of 12 month MCH DV screening and care intervention with 24 month follow-up. The study was set in community-based MCH nurse teams (91 centres, 163 nurses) in north-west Melbourne, Australia. Eight eligible teams were recruited. Team randomisation occurred at a public meeting using opaque envelopes. Teams were unable to be blinded. The intervention was informed by Normalisation Process Theory, the nurse-designed good practice model incorporated nurse mentors, strengthened relationships with DV services, nurse safety, a self-completion maternal health screening checklist at three or four month consultations and DV clinical guidelines. Usual care involved government mandated face-to-face DV screening at four weeks postpartum and follow-up as required. Primary outcomes were MCH team screening, disclosure, safety planning and referral rates from routine government data and a postal survey sent to 10,472 women with babies ≤ 12 months in study areas. Secondary outcomes included DV prevalence (Composite Abuse Scale, CAS) and harm measures (postal survey). No significant differences were found in routine screening at four months (IG 2,330/6,381 consultations (36.5 %) versus CG 1,792/7,638 consultations (23.5 %), RR = 1.56 CI 0.96-2.52) but data from maternal health checklists (n = 2,771) at three month IG consultations showed average screening rates of 63.1 %. Two years post-intervention, IG safety planning rates had increased from three (RR 2.95, CI 1.11-7.82) to four times those of CG (RR 4.22 CI 1.64-10.9). Referrals remained low in both intervention groups (IGs

Efficacy of community-based physiotherapy networks for patients with Parkinson's disease: a cluster-randomised trial.

Science.gov (United States)

Munneke, Marten; Nijkrake, Maarten J; Keus, Samyra Hj; Kwakkel, Gert; Berendse, Henk W; Roos, Raymund Ac; Borm, George F; Adang, Eddy M; Overeem, Sebastiaan; Bloem, Bastiaan R

2010-01-01

Many patients with Parkinson's disease are treated with physiotherapy. We have developed a community-based professional network (ParkinsonNet) that involves training of a selected number of expert physiotherapists to work according to evidence-based recommendations, and structured referrals to these trained physiotherapists to increase the numbers of patients they treat. We aimed to assess the efficacy of this approach for improving health-care outcomes. Between February, 2005, and August, 2007, we did a cluster-randomised trial with 16 clusters (defined as community hospitals and their catchment area). Clusters were randomly allocated by use of a variance minimisation algorithm to ParkinsonNet care (n=8) or usual care (n=8). Patients were assessed at baseline and at 8, 16, and 24 weeks of follow-up. The primary outcome was a patient preference disability score, the patient-specific index score, at 16 weeks. Health secondary outcomes were functional mobility, mobility-related quality of life, and total societal costs over 24 weeks. Analysis was by intention to treat. This trial is registered, number NCT00330694. We included 699 patients. Baseline characteristics of the patients were comparable between the ParkinsonNet clusters (n=358) and usual-care clusters (n=341). The primary endpoint was similar for patients within the ParkinsonNet clusters (mean 47.7, SD 21.9) and control clusters (48.3, 22.4). Health secondary endpoints were also similar for patients in both study groups. Total costs over 24 weeks were lower in ParkinsonNet clusters compared with usual-care clusters (difference euro727; 95% CI 56-1399). Implementation of ParkinsonNet networks did not change health outcomes for patients living in ParkinsonNet clusters. However, health-care costs were reduced in ParkinsonNet clusters compared with usual-care clusters. ZonMw; Netherlands Organisation for Scientific Research; Dutch Parkinson's Disease Society; National Parkinson Foundation; Stichting Robuust

Promoting Recruitment using Information Management Efficiently (PRIME): a stepped-wedge, cluster randomised trial of a complex recruitment intervention embedded within the REstart or Stop Antithrombotics Randomised Trial.

Science.gov (United States)

Maxwell, Amy E; Parker, Richard A; Drever, Jonathan; Rudd, Anthony; Dennis, Martin S; Weir, Christopher J; Al-Shahi Salman, Rustam

2017-12-28

Few interventions are proven to increase recruitment in clinical trials. Recruitment to RESTART, a randomised controlled trial of secondary prevention after stroke due to intracerebral haemorrhage, has been slower than expected. Therefore, we sought to investigate an intervention to boost recruitment to RESTART. We conducted a stepped-wedge, cluster randomised trial of a complex intervention to increase recruitment, embedded within the RESTART trial. The primary objective was to investigate if the PRIME complex intervention (a recruitment co-ordinator who conducts a recruitment review, provides access to bespoke stroke audit data exports, and conducts a follow-up review after 6 months) increases the recruitment rate to RESTART. We included 72 hospital sites located in England, Wales, or Scotland that were active in RESTART in June 2015. All sites began in the control state and were allocated using block randomisation stratified by hospital location (Scotland versus England/Wales) to start the complex intervention in one of 12 different months. The primary outcome was the number of patients randomised into RESTART per month per site. We quantified the effect of the complex intervention on the primary outcome using a negative binomial, mixed model adjusting for site, December/January months, site location, and background time trends in recruitment rate. We recruited and randomised 72 sites and recorded their monthly recruitment to RESTART over 24 months (March 2015 to February 2017 inclusive), providing 1728 site-months of observations for the primary analysis. The adjusted rate ratio for the number of patients randomised per month after allocation to the PRIME complex intervention versus control time before allocation to the PRIME complex intervention was 1.06 (95% confidence interval 0.55 to 2.03, p = 0.87). Although two thirds of respondents to the 6-month follow-up questionnaire agreed that the audit reports were useful, only six patients were reported to

A Cluster Randomised Controlled Trial of a Brief Child Health Nurse Intervention to Reduce Infant Secondhand Smoke Exposure.

Science.gov (United States)

Daly, Justine B; Freund, Megan; Burrows, Sally; Considine, Robyn; Bowman, Jennifer A; Wiggers, John H

2017-01-01

Background Exposure to secondhand smoke (SHS) is a significant contributor to ill health in children. A study was undertaken to determine the effectiveness of two brief multi-strategic child health nurse delivered interventions in: decreasing the prevalence of infants exposed to SHS; decreasing the prevalence of smoking amongst parent/carers of infants and increasing the prevalence of household smoking bans. Methods This study was a 3 arm, cluster randomised controlled trial. Clusters were 39 community based well child health clinics in one local area health service. Clinics were stratified according to annual number of client appointments and then randomly assigned in a 1:1:1 ratio, (Intervention 1: Intervention 2: Control), with 13 clinics in each cluster. Parents/carers of infants in the intervention groups received a brief multi-strategic intervention from child health nurses during clinic consultations. Treatment condition 1 included computer delivered risk assessment and feedback and nurse brief advice. Treatment condition 2 included all elements of Treatment condition 1 with the addition of biochemical feedback of infant SHS exposure. Results When compared to the Control group at 12 months, no significant differences in the prevalence of infant exposure to SHS were detected from baseline to follow-up for Treatment condition 1 (OR 1.16, 95 % CI 0.73-1.85, p = 0.53) or Treatment condition 2 (OR 1.30, 95 % CI 0.88-1.92, p = 0.19) Similarly, no significant differences were detected in the proportion of parent/carers who reported that they were smokers (T1:OR 0.95, 95 % CI 0.78-1.15, p = 0.58 and T2:OR 0.97, 95 % CI 0.80-1.18, p = 0.77), or in the proportion of households reported to have a complete smoking ban (T1:OR 1.21, 95 % CI 0.89-1.64, p = 0.23 and T2:OR 1.06, 95 % CI 0.79-1.43, p = 0.68). Conclusions Further research is required to identify effective interventions that can be consistently provided by child health nurses if the

A quasiparticle-based multi-reference coupled-cluster method.

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Rolik, Zoltán; Kállay, Mihály

2014-10-07

The purpose of this paper is to introduce a quasiparticle-based multi-reference coupled-cluster (MRCC) approach. The quasiparticles are introduced via a unitary transformation which allows us to represent a complete active space reference function and other elements of an orthonormal multi-reference (MR) basis in a determinant-like form. The quasiparticle creation and annihilation operators satisfy the fermion anti-commutation relations. On the basis of these quasiparticles, a generalization of the normal-ordered operator products for the MR case can be introduced as an alternative to the approach of Mukherjee and Kutzelnigg [Recent Prog. Many-Body Theor. 4, 127 (1995); Mukherjee and Kutzelnigg, J. Chem. Phys. 107, 432 (1997)]. Based on the new normal ordering any quasiparticle-based theory can be formulated using the well-known diagram techniques. Beyond the general quasiparticle framework we also present a possible realization of the unitary transformation. The suggested transformation has an exponential form where the parameters, holding exclusively active indices, are defined in a form similar to the wave operator of the unitary coupled-cluster approach. The definition of our quasiparticle-based MRCC approach strictly follows the form of the single-reference coupled-cluster method and retains several of its beneficial properties. Test results for small systems are presented using a pilot implementation of the new approach and compared to those obtained by other MR methods.

Behavioural graded activity results in better exercise adherence and more physical activity than usual care in people with osteoarthritis: a cluster-randomised trial

NARCIS (Netherlands)

Pisters, M.F.; Veenhof, C.; de Bakker, D.H.; Schellevis, F.G.; Dekker, J.

2010-01-01

Question: Does behavioural graded activity result in better exercise adherence and more physical activity than usual care in people with osteoarthritis of the hip or knee? Design: Analysis of secondary outcomes of a cluster-randomised trial with concealed allocation, assessor blinding, and

Participatory women's groups and counselling through home visits to improve child growth in rural eastern India: protocol for a cluster randomised controlled trial.

Science.gov (United States)

Nair, Nirmala; Tripathy, Prasanta; Sachdev, Harshpal S; Bhattacharyya, Sanghita; Gope, Rajkumar; Gagrai, Sumitra; Rath, Shibanand; Rath, Suchitra; Sinha, Rajesh; Roy, Swati Sarbani; Shewale, Suhas; Singh, Vijay; Srivastava, Aradhana; Pradhan, Hemanta; Costello, Anthony; Copas, Andrew; Skordis-Worrall, Jolene; Haghparast-Bidgoli, Hassan; Saville, Naomi; Prost, Audrey

2015-04-15

Child stunting (low height-for-age) is a marker of chronic undernutrition and predicts children's subsequent physical and cognitive development. Around one third of the world's stunted children live in India. Our study aims to assess the impact, cost-effectiveness, and scalability of a community intervention with a government-proposed community-based worker to improve growth in children under two in rural India. The study is a cluster randomised controlled trial in two rural districts of Jharkhand and Odisha (eastern India). The intervention tested involves a community-based worker carrying out two activities: (a) one home visit to all pregnant women in the third trimester, followed by subsequent monthly home visits to all infants aged 0-24 months to support appropriate feeding, infection control, and care-giving; (b) a monthly women's group meeting using participatory learning and action to catalyse individual and community action for maternal and child health and nutrition. Both intervention and control clusters also receive an intervention to strengthen Village Health Sanitation and Nutrition Committees. The unit of randomisation is a purposively selected cluster of approximately 1000 population. A total of 120 geographical clusters covering an estimated population of 121,531 were randomised to two trial arms: 60 clusters in the intervention arm receive home visits, group meetings, and support to Village Health Sanitation and Nutrition Committees; 60 clusters in the control arm receive support to Committees only. The study participants are pregnant women identified in the third trimester of pregnancy and their children (n = 2520). Mothers and their children are followed up at seven time points: during pregnancy, within 72 hours of delivery, and at 3, 6, 9, 12 and 18 months after birth. The trial's primary outcome is children's mean length-for-age Z scores at 18 months. Secondary outcomes include wasting and underweight at all time points, birth weight, growth

Clustered iterative stochastic ensemble method for multi-modal calibration of subsurface flow models

KAUST Repository

Elsheikh, Ahmed H.

2013-05-01

A novel multi-modal parameter estimation algorithm is introduced. Parameter estimation is an ill-posed inverse problem that might admit many different solutions. This is attributed to the limited amount of measured data used to constrain the inverse problem. The proposed multi-modal model calibration algorithm uses an iterative stochastic ensemble method (ISEM) for parameter estimation. ISEM employs an ensemble of directional derivatives within a Gauss-Newton iteration for nonlinear parameter estimation. ISEM is augmented with a clustering step based on k-means algorithm to form sub-ensembles. These sub-ensembles are used to explore different parts of the search space. Clusters are updated at regular intervals of the algorithm to allow merging of close clusters approaching the same local minima. Numerical testing demonstrates the potential of the proposed algorithm in dealing with multi-modal nonlinear parameter estimation for subsurface flow models. © 2013 Elsevier B.V.

Multi-centre audit of VMAT planning and pre-treatment verification.

Science.gov (United States)

Jurado-Bruggeman, Diego; Hernández, Victor; Sáez, Jordi; Navarro, David; Pino, Francisco; Martínez, Tatiana; Alayrach, Maria-Elena; Ailleres, Norbert; Melero, Alejandro; Jornet, Núria

2017-08-01

We performed a multi-centre intercomparison of VMAT dose planning and pre-treatment verification. The aims were to analyse the dose plans in terms of dosimetric quality and deliverability, and to validate whether in-house pre-treatment verification results agreed with those of an external audit. The nine participating centres encompassed different machines, equipment, and methodologies. Two mock cases (prostate and head and neck) were planned using one and two arcs. A plan quality index was defined to compare the plans and different complexity indices were calculated to check their deliverability. We compared gamma index pass rates using the centre's equipment and methodology to those of an external audit (global 3D gamma, absolute dose differences, 10% of maximum dose threshold). Log-file analysis was performed to look for delivery errors. All centres fulfilled the dosimetric goals but plan quality and delivery complexity were heterogeneous and uncorrelated, depending on the manufacturer and the planner's methodology. Pre-treatment verifications results were within tolerance in all cases for gamma 3%-3mm evaluation. Nevertheless, differences between the external audit and in-house measurements arose due to different equipment or methodology, especially for 2%-2mm criteria with differences up to 20%. No correlation was found between complexity indices and verification results amongst centres. All plans fulfilled dosimetric constraints, but plan quality and complexity did not correlate and were strongly dependent on the planner and the vendor. In-house measurements cannot completely replace external audits for credentialing. Copyright © 2017 Elsevier B.V. All rights reserved.

Population deworming every 6 months with albendazole in 1 million pre-school children in north India: DEVTA, a cluster-randomised trial

Science.gov (United States)

Awasthi, Shally; Peto, Richard; Read, Simon; Richards, Susan M; Pande, Vinod; Bundy, Donald; the DEVTA (Deworming and Enhanced Vitamin A) team

2013-01-01

Summary Background In north India many pre-school children are underweight, many have intestinal worms, and 2–3% die at ages 1·0–6·0 years. We used the state-wide Integrated Child Development Service (ICDS) infrastructure to help to assess any effects of regular deworming on mortality. Methods Participants in this cluster-randomised study were children in catchment areas of 8338 ICDS-staffed village child-care centres (under-5 population 1 million) in 72 administrative blocks. Groups of four neighbouring blocks were cluster-randomly allocated in Oxford between 6-monthly vitamin A (retinol capsule of 200 000 IU retinyl acetate in oil, to be cut and dripped into the child's mouth every 6 months), albendazole (400 mg tablet every 6 months), both, or neither (open control). Analyses of albendazole effects are by block (36 vs 36 clusters). The study spanned 5 calendar years, with 11 6-monthly mass-treatment days for all children then aged 6–72 months. Annually, one centre per block was randomly selected and visited by a study team 1–5 months after any trial deworming to sample faeces (for presence of worm eggs, reliably assessed only after mid-study), weigh children, and interview caregivers. Separately, all 8338 centres were visited every 6 months to monitor pre-school deaths (100 000 visits, 25 000 deaths at age 1·0–6·0 years [the primary outcome]). This trial is registered at ClinicalTrials.gov, NCT00222547. Findings Estimated compliance with 6-monthly albendazole was 86%. Among 2589 versus 2576 children surveyed during the second half of the study, nematode egg prevalence was 16% versus 36%, and most infection was light. After at least 2 years of treatment, weight at ages 3·0–6·0 years (standardised to age 4·0 years, 50% male) was 12·72 kg albendazole versus 12·68 kg control (difference 0·04 kg, 95% CI −0·14 to 0·21, p=0·66). Comparing the 36 albendazole-allocated versus 36 control blocks in analyses of the primary outcome, deaths

The evaluation of enhanced feedback interventions to reduce unnecessary blood transfusions (AFFINITIE): protocol for two linked cluster randomised factorial controlled trials.

Science.gov (United States)

Hartley, Suzanne; Foy, Robbie; Walwyn, Rebecca E A; Cicero, Robert; Farrin, Amanda J; Francis, Jill J; Lorencatto, Fabiana; Gould, Natalie J; Grant-Casey, John; Grimshaw, Jeremy M; Glidewell, Liz; Michie, Susan; Morris, Stephen; Stanworth, Simon J

2017-07-03

Blood for transfusion is a frequently used clinical intervention, and is also a costly and limited resource with risks. Many transfusions are given to stable and non-bleeding patients despite no clear evidence of benefit from clinical studies. Audit and feedback (A&F) is widely used to improve the quality of healthcare, including appropriate use of blood. However, its effects are often inconsistent, indicating the need for coordinated research including more head-to-head trials comparing different ways of delivering feedback. A programmatic series of research projects, termed the 'Audit and Feedback INterventions to Increase evidence-based Transfusion practIcE' (AFFINITIE) programme, aims to test different ways of developing and delivering feedback within an existing national audit structure. The evaluation will comprise two linked 2×2 factorial, cross-sectional cluster-randomised controlled trials. Each trial will estimate the effects of two feedback interventions, 'enhanced content' and 'enhanced follow-on support', designed in earlier stages of the AFFINITIE programme, compared to current practice. The interventions will be embedded within two rounds of the UK National Comparative Audit of Blood Transfusion (NCABT) focusing on patient blood management in surgery and use of blood transfusions in patients with haematological malignancies. The unit of randomisation will be National Health Service (NHS) trust or health board. Clusters providing care relevant to the audit topics will be randomised following each baseline audit (separately for each trial), with stratification for size (volume of blood transfusions) and region (Regional Transfusion Committee). The primary outcome for each topic will be the proportion of patients receiving a transfusion coded as unnecessary. For each audit topic a linked, mixed-method fidelity assessment and cost-effectiveness analysis will be conducted in parallel to the trial. AFFINITIE involves a series of studies to explore how A

The value of episodic, intensive blood glucose monitoring in non-insulin treated persons with Type 2 Diabetes: design of the Structured Testing Program (STeP) study, a cluster-randomised, clinical trial [NCT00674986].

Science.gov (United States)

Polonsky, William; Fisher, Lawrence; Schikman, Charles; Hinnen, Deborah; Parkin, Christopher; Jelsovsky, Zhihong; Amstutz, Linda; Schweitzer, Matthias; Wagner, Robin

2010-05-18

The value and utility of self-monitoring of blood glucose (SMBG) in non-insulin treated T2DM has yet to be clearly determined. Findings from studies in this population have been inconsistent, due mainly to design differences and limitations, including the prescribed frequency and timing of SMBG, role of the patient and physician in responding to SMBG results, inclusion criteria that may contribute to untoward floor effects, subject compliance, and cross-arm contamination. We have designed an SMBG intervention study that attempts to address these issues. The Structured Testing Program (STeP) study is a 12-month, cluster-randomised, multi-centre clinical trial to evaluate whether poorly controlled (HbA1c >or= 7.5%), non-insulin treated T2DM patients will benefit from a comprehensive, integrated physician/patient intervention using structured SMBG in US primary care practices. Thirty-four practices will be recruited and randomly assigned to an active control group (ACG) that receives enhanced usual care or to an enhanced usual care group plus structured SMBG (STG). A total of 504 patients will be enrolled; eligible patients at each site will be randomly selected using a defined protocol. Anticipated attrition of 20% will yield a sample size of at least 204 per arm, which will provide a 90% power to detect a difference of at least 0.5% in change from baseline in HbA1c values, assuming a common standard deviation of 1.5%. Differences in timing and degree of treatment intensification, cost effectiveness, and changes in patient self-management behaviours, mood, and quality of life (QOL) over time will also be assessed. Analysis of change in HbA1c and other dependent variables over time will be performed using both intent-to-treat and per protocol analyses. Trial results will be available in 2010. The intervention and trial design builds upon previous research by emphasizing appropriate and collaborative use of SMBG by both patients and physicians. Utilization of per

The value of episodic, intensive blood glucose monitoring in non-insulin treated persons with type 2 diabetes: Design of the Structured Testing Program (STeP Study, a cluster-randomised, clinical trial [NCT00674986

Directory of Open Access Journals (Sweden)

Jelsovsky Zhihong

2010-05-01

Full Text Available Abstract Background The value and utility of self-monitoring of blood glucose (SMBG in non-insulin treated T2DM has yet to be clearly determined. Findings from studies in this population have been inconsistent, due mainly to design differences and limitations, including the prescribed frequency and timing of SMBG, role of the patient and physician in responding to SMBG results, inclusion criteria that may contribute to untoward floor effects, subject compliance, and cross-arm contamination. We have designed an SMBG intervention study that attempts to address these issues. Methods/design The Structured Testing Program (STeP study is a 12-month, cluster-randomised, multi-centre clinical trial to evaluate whether poorly controlled (HbA1c ≥ 7.5%, non-insulin treated T2DM patients will benefit from a comprehensive, integrated physician/patient intervention using structured SMBG in US primary care practices. Thirty-four practices will be recruited and randomly assigned to an active control group (ACG that receives enhanced usual care or to an enhanced usual care group plus structured SMBG (STG. A total of 504 patients will be enrolled; eligible patients at each site will be randomly selected using a defined protocol. Anticipated attrition of 20% will yield a sample size of at least 204 per arm, which will provide a 90% power to detect a difference of at least 0.5% in change from baseline in HbA1c values, assuming a common standard deviation of 1.5%. Differences in timing and degree of treatment intensification, cost effectiveness, and changes in patient self-management behaviours, mood, and quality of life (QOL over time will also be assessed. Analysis of change in HbA1c and other dependent variables over time will be performed using both intent-to-treat and per protocol analyses. Trial results will be available in 2010. Discussion The intervention and trial design builds upon previous research by emphasizing appropriate and collaborative use of

REFOCUS Trial: protocol for a cluster randomised controlled trial of a pro-recovery intervention within community based mental health teams.

Science.gov (United States)

Slade, Mike; Bird, Victoria; Le Boutillier, Clair; Williams, Julie; McCrone, Paul; Leamy, Mary

2011-11-23

There is a consensus about the importance of 'recovery' in mental health services, but the evidence base is limited. A two centre, cluster randomised controlled trial. Participants are community-based mental health teams, and service users aged 18-65 years with a primary clinical diagnosis of psychosis. In relation to the REFOCUS Manual researchintorecovery.com/refocus, which describes a 12-month, pro-recovery intervention based on the REFOCUS Model, the objectives are: (1) To establish the effectiveness of the intervention described in the REFOCUS Manual; (2) To validate the REFOCUS Model; (3) To establish and optimise trial parameters for the REFOCUS Manual; and (4) To understand the relationship between clinical outcomes and recovery outcomes. The hypothesis for the main study is that service users in the intervention arm will experience significantly greater increases in measures of personal recovery (as measured by the QPR) compared to service users receiving care from control teams. The hypothesis for the secondary study is that black service users in the intervention arm will experience significantly greater increases in measures of personal recovery (as measured by the QPR) and client satisfaction (as measured by the CSQ) compared to Black service users receiving care from control teams. The intervention comprises treatment as usual plus two components: recovery-promoting relationships and working practices. The control condition is treatment as usual. The primary outcme is the Process of Recovery Questionnaire (QPR). Secondary outcomes are satisfaction, Goal setting - Personal Primary Outcome, hope, well-being, empowerment, and quality of life. Primary outcomes for the secondary study will be QPR and satisfaction. Cost data will be estimated, and clinical outcomes will also be reported (symptomatology, need, social disability, functioning). 29 teams (15 intervention and 14 control) will be randomised. Within each team, 15 services users will be randomly

Design of Lamifuse: a randomised, multi-centre controlled trial comparing laminectomy without or with dorsal fusion for cervical myeloradiculopathy

Directory of Open Access Journals (Sweden)

Grotenhuis J André

2007-11-01

Full Text Available Abstract Background laminectomy is a valuable surgical treatment for some patients with a cervical radiculomyelopathy due to cervical spinal stenosis. More recently attention has been given to motion of the spinal cord over spondylotic spurs as a cause of myelopathic changes. Immobilisation by fusion could have a positive effect on the recovery of myelopathic signs or changes. This has never been investigated in a prospective, randomised trial. Lamifuse is an acronyme for laminectomy and fusion. Methods/Design Lamifuse is a multicentre, randomised controlled trial comparing laminectomy with and without fusion in patients with a symptomatic cervical canal stenosis. The study population will be enrolled from patients that are 60 years or older with myelopathic signs and/or symptoms due to a cervical canal stenosis. A kyphotis shape of the cervical spine is an exclusion criterium. Each treatment arm needs 30 patients. Discussion This study will contribute to the discussion whether additional fusion after a cervical laminectomy results in a better clinical outcome. ISRCT number ISRCTN72800446

A cluster-randomised trial of a multifaceted quality improvement intervention in Brazilian intensive care units (Checklist-ICU trial): statistical analysis plan.

Science.gov (United States)

Damiani, Lucas P; Cavalcanti, Alexandre B; Moreira, Frederico R; Machado, Flavia; Bozza, Fernando A; Salluh, Jorge I F; Campagnucci, Valquiria P; Normilio-Silva, Karina; Chiattone, Viviane C; Angus, Derek C; Berwanger, Otavio; Chou H Chang, Chung-

2015-06-01

The Checklist During Multidisciplinary Visits for Reduction of Mortality in Intensive Care Units (Checklist- ICU) trial is a pragmatic, two-arm, cluster-randomised trial involving 118 intensive care units in Brazil, with the primary objective of determining if a multifaceted qualityimprovement intervention with a daily checklist, definition of daily care goals during multidisciplinary daily rounds and clinician prompts can reduce inhospital mortality. To describe our trial statistical analysis plan (SAP). This is an ongoing trial conducted in two phases. In the preparatory observational phase, we collect three sets of baseline data: ICU characteristics; patient characteristics, processes of care and outcomes; and completed safety attitudes questionnaires (SAQs). In the randomised phase, ICUs are assigned to the experimental or control arms and we collect patient data and repeat the SAQ. Our SAP includes the prespecified model for the primary and secondary outcome analyses, which account for the cluster-randomised design and availability of baseline data. We also detail the multiple mediation models that we will use to assess our secondary hypothesis (that the effect of the intervention on inhospital mortality is mediated not only through care processes targeted by the checklist, but also through changes in safety culture). We describe our approach to sensitivity and subgroup analyses and missing data. We report our SAP before closing our study database and starting analysis. We anticipate that this should prevent analysis bias and enhance the utility of results.

Image Segmentation Method Using Fuzzy C Mean Clustering Based on Multi-Objective Optimization

Science.gov (United States)

Chen, Jinlin; Yang, Chunzhi; Xu, Guangkui; Ning, Li

2018-04-01

Image segmentation is not only one of the hottest topics in digital image processing, but also an important part of computer vision applications. As one kind of image segmentation algorithms, fuzzy C-means clustering is an effective and concise segmentation algorithm. However, the drawback of FCM is that it is sensitive to image noise. To solve the problem, this paper designs a novel fuzzy C-mean clustering algorithm based on multi-objective optimization. We add a parameter λ to the fuzzy distance measurement formula to improve the multi-objective optimization. The parameter λ can adjust the weights of the pixel local information. In the algorithm, the local correlation of neighboring pixels is added to the improved multi-objective mathematical model to optimize the clustering cent. Two different experimental results show that the novel fuzzy C-means approach has an efficient performance and computational time while segmenting images by different type of noises.

Chemical Compositions of Stars in the Globular Cluster NGC 3201: Tracers of Multi-Epoch Star Formation

Science.gov (United States)

Simmerer, Jennifer A.; Ivans, I. I.; Filler, D.

2012-01-01

The retrograde halo globular cluster NGC 3201 contains stars of substantially different iron abundance ([Fe/H]), a property that puts it at odds with the vast majority of the Galactic cluster system. Though its unusual orbit prompted speculation that NGC 3201 was the remnant of a captured object, much like the multi-metallicity globular cluster Omega Centauri, NGC 3201 is much less massive than Omega Centauri and all of the other halo globular clusters that have internal metallicity variations. We present the abundances of 21 elements in 24 red giant branch stars in NGC 3201 based on high-resolution (R 40,000), high signal-to-noise (S/N 70) spectra. We find that the detailed abundance pattern of NGC 3201 is unique amongst multi-metallicity halo clusters. Unlike M22, Omega Centauri, and NGC 1851, neither metal-poor nor metal-rich stars show any evidence of s-process enrichment (a product of the advanced evolution of low- and intermediate-mass stars). We find that while Na, O, and Al vary from star to star as is typical in globular clusters, there is no systematic difference between the abundance pattern in the metal-poor cluster stars and that of the metal-rich cluster stars. Furthermore, we find that the metallicity variations in NGC 3201 are independent of the well-known Na-O anticorrelation, which separates it from every other multi-metallicity cluster. In the context of a multi-episode star formation model, this implies that NGC 3201 began life with the [Fe/H] variations we measure now.

Building Multi-Discipline, Multi-Format Digital Libraries Using Clusters and Buckets. Degree rewarded by Old Dominion Univ. on Aug. 1997

Science.gov (United States)

Nelson, Michael L.

1997-01-01

Our objective was to study the feasibility of extending the Dienst protocol to enable a multi-discipline, multi-format digital library. We implemented two new technologies: cluster functionality and publishing buckets. We have designed a possible implementation of clusters and buckets, and have prototyped some aspects of the resultant digital library. Currently, digital libraries are segregated by the disciplines they serve (computer science, aeronautics, etc.), and by the format of their holdings (reports, software, datasets, etc.). NCSTRL+ is a multi-discipline, multi-format digital library (DL) prototype created to explore the feasibility of the design and implementation issues involved with created a unified, canonical scientific and technical information (STI) DL. NCSTRL+ is based on the Networked Computer Science Technical Report Library (NCSTRL), a World Wide Web (WWW) accessible DL that provides access to over 80 university departments and laboratories. We have extended the Dienst protocol (version 4.1.8), the protocol underlying NCSTRL, to provide the ability to cluster independent collections into a logically centralized DL based upon subject category classification, type of organization, and genre of material. The concept of buckets provides a mechanism for publishing and managing logically linked entities with multiple data formats.

Cost-effectiveness of the Australian Medical Sheepskin for the prevention of pressure ulcers in somatic nursing home patients: study protocol for a prospective multi-centre randomised controlled trial (ISRCTN17553857).

Science.gov (United States)

Mistiaen, Patriek; Achterberg, Wilco; Ament, Andre; Halfens, Ruud; Huizinga, Janneke; Montgomery, Ken; Post, Henri; Francke, Anneke L

2008-01-07

Pressure ulcers are a major problem, especially in nursing home patients, although they are regarded as preventable and there are many pressure relieving methods and materials. One such pressure relieving material is the recently developed Australian Medical Sheepskin, which has been shown in two randomized controlled trials 12 to be an effective intervention in the prevention of sacral pressure ulcers in hospital patients. However, the use of sheepskins has been debated and in general discouraged by most pressure ulcer working groups and pressure ulcer guidelines, but these debates were based on old forms of sheepskins. Furthermore, nothing is yet known about the (cost-)effectiveness of the Australian Medical sheepskin in nursing home patients. The objective of this study is to assess the effects and costs of the use of the Australian Medical Sheepskin combined with usual care with regard to the prevention of sacral pressure ulcers in somatic nursing home patients, versus usual care only. In a multi-centre randomised controlled trial 750 patients admitted for a primarily somatic reason to one of the five participating nursing homes, and not having pressure ulcers on the sacrum at admission, will be randomized to either usual care only or usual care plus the use of the Australian Medical Sheepskin as an overlay on the mattress. Outcome measures are: incidence of sacral pressure ulcers in the first month after admission; sacrum pressure ulcer free days; costs; patient comfort; and ease of use. The skin of all the patients will be observed once a day from admission on for 30 days. Patient characteristics and pressure risk scores are assessed at admission and at day 30 after it. Additional to the empirical phase, systematic reviews will be performed in order to obtain data for economic weighting and modelling. The protocol is registered in the Controlled Trial Register as ISRCTN17553857.

Evaluation of the preliminary auditory profile test battery in an international multi-centre study

NARCIS (Netherlands)

van Esch, T.E.M.; Kollmeier, B.; Vormann, M.; Lijzenga, J.; Houtgast, T.; Hallgren, M.; Larsby, B.; Athalye, S.P.; Lutman, M.E.; Dreschler, W.A.

2013-01-01

Objective: This paper describes the composition and international multi-centre evaluation of a battery of tests termed the preliminary auditory profile. It includes measures of loudness perception, listening effort, speech perception, spectral and temporal resolution, spatial hearing, self-reported

Schedulability-Driven Frame Packing for Multi-Cluster Distributed Embedded Systems

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2003-01-01

We present an approach to frame packing for multi-cluster distributed embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways. In our approach, the application messages are packed into frames such that the application is schedulable. Thus, we have...... also proposed a schedulability analysis for applications consisting of mixed event-triggered and time-triggered processes and messages, and a worst case queuing delay analysis for the gateways, responsible for routing inter-cluster traffic. Optimization heuristics for frame packing aiming at producing...... a schedulable system have been proposed. Extensive experiments and a real-life example show the efficiency of our frame-packing approach....

Pilot cluster randomised controlled trial of flooring to reduce injuries from falls in elderly care units: study protocol.

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Drahota, Amy; Gal, Diane; Windsor, Julie; Dixon, Simon; Udell, Julie; Ward, Derek; Soilemezi, Dia; Dean, Taraneh; Severs, Martin

2011-12-01

Falls are an issue disproportionately affecting older people who are at increased risk of falls and injury. This protocol describes a pilot study investigating shock-absorbing flooring for fall-related injuries in wards for older people. To inform future research by evaluating fall-related injuries on the intervention and existing flooring, assessing the sustainability of the flooring in ward environments, estimating the cost-effectiveness of the floor and assessing how the floor affects patients and other users. This study uses mixed methods a pilot cluster randomised controlled trial, observation via mechanical testing and interviews. Eight participating wards (clusters) are randomised using a computer-generated list. No blinding is incorporated into the study. Each site has a baseline period of approximately 6 months. Then, four sites receive the intervention floor, while four continue using standard floors. Sites are then followed up for approximately 1 year. Any person admitted to a bed in the 'study area' of a participating ward can be entered into the trial. Orientated patients, visitors and any hospital staff who use the floor in a study area are eligible for inclusion in an interview. An 8.3 mm thick vinyl floor covering with polyvinyl chloride foam backing (Tarkett Omnisports EXCEL). The primary outcome is fall-related injuries. Severity of injuries, falls, cost-effectiveness, user views and mechanical performance (shock absorbency and slip resistance) are also being assessed.

Cluster-randomised controlled trials of individual and combined water, sanitation, hygiene and nutritional interventions in rural Bangladesh and Kenya: the WASH Benefits study design and rationale

Science.gov (United States)

Arnold, Benjamin F; Null, Clair; Luby, Stephen P; Unicomb, Leanne; Stewart, Christine P; Dewey, Kathryn G; Ahmed, Tahmeed; Ashraf, Sania; Christensen, Garret; Clasen, Thomas; Dentz, Holly N; Fernald, Lia C H; Haque, Rashidul; Hubbard, Alan E; Kariger, Patricia; Leontsini, Elli; Lin, Audrie; Njenga, Sammy M; Pickering, Amy J; Ram, Pavani K; Tofail, Fahmida; Winch, Peter J; Colford, John M

2013-01-01

Introduction Enteric infections are common during the first years of life in low-income countries and contribute to growth faltering with long-term impairment of health and development. Water quality, sanitation, handwashing and nutritional interventions can independently reduce enteric infections and growth faltering. There is little evidence that directly compares the effects of these individual and combined interventions on diarrhoea and growth when delivered to infants and young children. The objective of the WASH Benefits study is to help fill this knowledge gap. Methods and analysis WASH Benefits includes two cluster-randomised trials to assess improvements in water quality, sanitation, handwashing and child nutrition—alone and in combination—to rural households with pregnant women in Kenya and Bangladesh. Geographically matched clusters (groups of household compounds in Bangladesh and villages in Kenya) will be randomised to one of six intervention arms or control. Intervention arms include water quality, sanitation, handwashing, nutrition, combined water+sanitation+handwashing (WSH) and WSH+nutrition. The studies will enrol newborn children (N=5760 in Bangladesh and N=8000 in Kenya) and measure outcomes at 12 and 24 months after intervention delivery. Primary outcomes include child length-for-age Z-scores and caregiver-reported diarrhoea. Secondary outcomes include stunting prevalence, markers of environmental enteropathy and child development scores (verbal, motor and personal/social). We will estimate unadjusted and adjusted intention-to-treat effects using semiparametric estimators and permutation tests. Ethics and dissemination Study protocols have been reviewed and approved by human subjects review boards at the University of California, Berkeley, Stanford University, the International Centre for Diarrheal Disease Research, Bangladesh, the Kenya Medical Research Institute, and Innovations for Poverty Action. Independent data safety monitoring

Community-led trials: Intervention co-design in a cluster randomised controlled trial.

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Andersson, Neil

2017-05-30

In conventional randomised controlled trials (RCTs), researchers design the interventions. In the Camino Verde trial, each intervention community designed its own programmes to prevent dengue. Instead of fixed actions or menus of activities to choose from, the trial randomised clusters to a participatory research protocol that began with sharing and discussing evidence from a local survey, going on to local authorship of the action plan for vector control.Adding equitable stakeholder engagement to RCT infrastructure anchors the research culturally, making it more meaningful to stakeholders. Replicability in other conditions is straightforward, since all intervention clusters used the same engagement protocol to discuss and to mobilize for dengue prevention. The ethical codes associated with RCTs play out differently in community-led pragmatic trials, where communities essentially choose what they want to do. Several discussion groups in each intervention community produced multiple plans for prevention, recognising different time lines. Some chose fast turnarounds, like elimination of breeding sites, and some chose longer term actions like garbage disposal and improving water supplies.A big part of the skill set for community-led trials is being able to stand back and simply support communities in what they want to do and how they want to do it, something that does not come naturally to many vector control programs or to RCT researchers. Unexpected negative outcomes can come from the turbulence implicit in participatory research. One example was the gender dynamic in the Mexican arm of the Camino Verde trial. Strong involvement of women in dengue control activities seems to have discouraged men in settings where activity in public spaces or outside of the home would ordinarily be considered a "male competence".Community-led trials address the tension between one-size-fits-all programme interventions and local needs. Whatever the conventional wisdom about how

Community-led trials: Intervention co-design in a cluster randomised controlled trial

Directory of Open Access Journals (Sweden)

Neil Andersson

2017-05-01

Full Text Available Abstract In conventional randomised controlled trials (RCTs, researchers design the interventions. In the Camino Verde trial, each intervention community designed its own programmes to prevent dengue. Instead of fixed actions or menus of activities to choose from, the trial randomised clusters to a participatory research protocol that began with sharing and discussing evidence from a local survey, going on to local authorship of the action plan for vector control. Adding equitable stakeholder engagement to RCT infrastructure anchors the research culturally, making it more meaningful to stakeholders. Replicability in other conditions is straightforward, since all intervention clusters used the same engagement protocol to discuss and to mobilize for dengue prevention. The ethical codes associated with RCTs play out differently in community-led pragmatic trials, where communities essentially choose what they want to do. Several discussion groups in each intervention community produced multiple plans for prevention, recognising different time lines. Some chose fast turnarounds, like elimination of breeding sites, and some chose longer term actions like garbage disposal and improving water supplies. A big part of the skill set for community-led trials is being able to stand back and simply support communities in what they want to do and how they want to do it, something that does not come naturally to many vector control programs or to RCT researchers. Unexpected negative outcomes can come from the turbulence implicit in participatory research. One example was the gender dynamic in the Mexican arm of the Camino Verde trial. Strong involvement of women in dengue control activities seems to have discouraged men in settings where activity in public spaces or outside of the home would ordinarily be considered a “male competence”. Community-led trials address the tension between one-size-fits-all programme interventions and local needs. Whatever the

Improvement of perinatal and newborn care in rural Pakistan through community-based strategies: a cluster-randomised effectiveness trial.

Science.gov (United States)

Bhutta, Zulfiqar A; Soofi, Sajid; Cousens, Simon; Mohammad, Shah; Memon, Zahid A; Ali, Imran; Feroze, Asher; Raza, Farrukh; Khan, Amanullah; Wall, Steve; Martines, Jose

2011-01-29

Newborn deaths account for 57% of deaths in children younger than 5 years in Pakistan. Although a large programme of trained lady health workers (LHWs) exists, the effectiveness of this training on newborn outcomes has not been studied. We aimed to evaluate the effectiveness of a community-based intervention package, principally delivered through LHWs working with traditional birth attendants and community health committees, for reduction of perinatal and neonatal mortality in a rural district of Pakistan. We undertook a cluster randomised trial between February, 2006, and March, 2008, in Hala and Matiari subdistricts, Pakistan. Catchment areas of primary care facilities and all affiliated LHWs were used to define clusters, which were allocated to intervention and control groups by restricted, stratified randomisation. The intervention package delivered by LHWs through group sessions consisted of promotion of antenatal care and maternal health education, use of clean delivery kits, facility births, immediate newborn care, identification of danger signs, and promotion of careseeking; control clusters received routine care. Independent data collectors undertook quarterly household surveillance to capture data for births, deaths, and household practices related to maternal and newborn care. Data collectors were masked to cluster allocation; those analysing data were not. The primary outcome was perinatal and all-cause neonatal mortality. Analysis was by intention to treat. This trial is registered, ISRCTN16247511. 16 clusters were assigned to intervention (23,353 households, 12,391 total births) and control groups (23,768 households, 11,443 total births). LHWs in the intervention clusters were able to undertake 4428 (63%) of 7084 planned group sessions, but were only able to visit 2943 neonates (24%) of a total 12,028 livebirths in their catchment villages. Stillbirths were reduced in intervention clusters (39·1 stillbirths per 1000 total births) compared with

Pragmatic randomised controlled trial of group psychoeducation versus group support in the maintenance of bipolar disorder

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Roberts Christopher

2011-07-01

Full Text Available Abstract Background Non-didactically delivered curriculum based group psychoeducation has been shown to be more effective than both group support in a specialist mood disorder centre in Spain (with effects lasting up to five years, and treatment as usual in Australia. It is unclear whether the specific content and form of group psychoeducation is effective or the chance to meet and work collaboratively with other peers. The main objective of this trial is to determine whether curriculum based group psychoeducation is more clinically and cost effective than unstructured peer group support. Methods/design Single blind two centre cluster randomised controlled trial of 21 sessions group psychoeducation versus 21 sessions group peer support in adults with bipolar 1 or 2 disorder, not in current episode but relapsed in the previous two years. Individual randomisation is to either group at each site. The groups are carefully matched for the number and type of therapists, length and frequency of the interventions and overall aim of the groups but differ in content and style of delivery. The primary outcome is time to next bipolar episode with measures of the therapeutic process, barriers and drivers to the effective delivery of the interventions and economic analysis. Follow up is for 96 weeks after randomisation. Discussion The trial has features of both an efficacy and an effectiveness trial design. For generalisability in England it is set in routine public mental health practice with a high degree of expert patient involvement. Trial Registration ISRCTN62761948 Funding National Institute for Health Research, England.

Participatory ergonomics to reduce exposure to psychosocial and physical risk factors for low back pain and neck pain: Results of a cluster randomised controlled trial

NARCIS (Netherlands)

Driessen, M.T.; Proper, K.I.; Anema, J.R.; Knol, D.L.; Bongers, P.M.; Beek, A.J. van der

2011-01-01

Objectives: This study investigated the effectiveness of the Stay@Work participatory ergonomics programme to reduce workers9 exposure to psychosocial and physical risk factors. Methods: 37 departments (n=3047 workers) from four Dutch companies participated in this cluster randomised controlled

Assessing the effectiveness of a patient-centred computer-based clinic intervention, Health-E You/Salud iTu, to reduce health disparities in unintended pregnancies among Hispanic adolescents: study protocol for a cluster randomised control trial.

Science.gov (United States)

Tebb, Kathleen P; Rodriguez, Felicia; Pollack, Lance M; Trieu, Sang Leng; Hwang, Loris; Puffer, Maryjane; Adams, Sally; Ozer, Elizabeth M; Brindis, Claire D

2018-01-10

Teen pregnancy rates in the USA remain higher than any other industrialised nation, and pregnancies among Hispanic adolescents are disproportionately high. Computer-based interventions represent a promising approach to address sexual health and contraceptive use disparities. Preliminary findings have demonstrated that the Health-E You/Salud iTu, computer application (app) is feasible to implement, acceptable to Latina adolescents and improves sexual health knowledge and interest in selecting an effective contraceptive method when used in conjunction with a healthcare visit. The app is now ready for efficacy testing. The purpose of this manuscript is to describe patient-centred approaches used both in developing and testing the Health-E You app and to present the research methods used to evaluate its effectiveness in improving intentions to use an effective method of contraception as well as actual contraceptive use. This study is designed to assess the effectiveness of a patient-centred computer-based clinic intervention, Health-E You/Salud  iTu, on its ability to reduce health disparities in unintended pregnancies among Latina adolescent girls. This study uses a cluster randomised control trial design in which 18 school-based health centers from the Los Angeles Unified School District were randomly assigned, at equal chance, to either the intervention ( Health-E You app) or control group. Analyses will examine differences between the control and intervention group's knowledge of and attitudes towards contraceptive use, receipt of contraception at the clinic visit and self-reported use of contraception at 3-month and 6-month follow-ups. The study began enrolling participants in August 2016, and a total of 1400 participants (700 per treatment group) are expected to be enrolled by March 2018. Ethics approval was obtained through the University of California, San Francisco Institutional Review Board. Results of this trial will be submitted for publication in peer

Gamma-ray and X-ray emission from the Galactic centre: hints on the nuclear star cluster formation history

Science.gov (United States)

Arca-Sedda, Manuel; Kocsis, Bence; Brandt, Timothy D.

2018-06-01

The Milky Way centre exhibits an intense flux in the gamma and X-ray bands, whose origin is partly ascribed to the possible presence of a large population of millisecond pulsars (MSPs) and cataclysmic variables (CVs), respectively. However, the number of sources required to generate such an excess is much larger than what is expected from in situ star formation and evolution, opening a series of questions about the formation history of the Galactic nucleus. In this paper we make use of direct N-body simulations to investigate whether these sources could have been brought to the Galactic centre by a population of star clusters that underwent orbital decay and formed the Galactic nuclear star cluster (NSC). Our results suggest that the gamma ray emission is compatible with a population of MSPs that were mass segregated in their parent clusters, while the X-ray emission is consistent with a population of CVs born via dynamical interactions in dense star clusters. Combining observations with our modelling, we explore how the observed γ ray flux can be related to different NSC formation scenarios. Finally, we show that the high-energy emission coming from the galactic central regions can be used to detect black holes heavier than 105M⊙ in nearby dwarf galaxies.

Ethical dilemmas of a large national multi-centre study in Australia: time for some consistency.

Science.gov (United States)

Driscoll, Andrea; Currey, Judy; Worrall-Carter, Linda; Stewart, Simon

2008-08-01

To examine the impact and obstacles that individual Institutional Research Ethics Committee (IRECs) had on a large-scale national multi-centre clinical audit called the National Benchmarks and Evidence-based National Clinical guidelines for Heart failure management programmes Study. Multi-centre research is commonplace in the health care system. However, IRECs continue to fail to differentiate between research and quality audit projects. The National Benchmarks and Evidence-based National Clinical guidelines for Heart failure management programmes study used an investigator-developed questionnaire concerning a clinical audit for heart failure programmes throughout Australia. Ethical guidelines developed by the National governing body of health and medical research in Australia classified the National Benchmarks and Evidence-based National Clinical guidelines for Heart failure management programmes Study as a low risk clinical audit not requiring ethical approval by IREC. Fifteen of 27 IRECs stipulated that the research proposal undergo full ethical review. None of the IRECs acknowledged: national quality assurance guidelines and recommendations nor ethics approval from other IRECs. Twelve of the 15 IRECs used different ethics application forms. Variability in the type of amendments was prolific. Lack of uniformity in ethical review processes resulted in a six- to eight-month delay in commencing the national study. Development of a national ethics application form with full ethical review by the first IREC and compulsory expedited review by subsequent IRECs would resolve issues raised in this paper. IRECs must change their ethics approval processes to one that enhances facilitation of multi-centre research which is now normative process for health services. The findings of this study highlight inconsistent ethical requirements between different IRECs. Also highlighted are the obstacles and delays that IRECs create when undertaking multi-centre clinical audits

Process evaluation of a cluster-randomised trial testing a pressure ulcer prevention care bundle: a mixed-methods study.

Science.gov (United States)

Roberts, Shelley; McInnes, Elizabeth; Bucknall, Tracey; Wallis, Marianne; Banks, Merrilyn; Chaboyer, Wendy

2017-02-13

As pressure ulcers contribute to significant patient burden and increased health care costs, their prevention is a clinical priority. Our team developed and tested a complex intervention, a pressure ulcer prevention care bundle promoting patient participation in care, in a cluster-randomised trial. The UK Medical Research Council recommends process evaluation of complex interventions to provide insight into why they work or fail and how they might be improved. This study aimed to evaluate processes underpinning implementation of the intervention and explore end-users' perceptions of it, in order to give a deeper understanding of its effects. A pre-specified, mixed-methods process evaluation was conducted as an adjunct to the main trial, guided by a framework for process evaluation of cluster-randomised trials. Data was collected across eight Australian hospitals but mainly focused on the four intervention hospitals. Quantitative and qualitative data were collected across the evaluation domains: recruitment, reach, intervention delivery and response to intervention, at both cluster and individual patient level. Quantitative data were analysed using descriptive and inferential statistics. Qualitative data were analysed using thematic analysis. In the context of the main trial, which found a 42% reduction in risk of pressure ulcer with the intervention that was not significant after adjusting for clustering and covariates, this process evaluation provides important insights. Recruitment and reach among clusters and individuals was high, indicating that patients, nurses and hospitals are willing to engage with a pressure ulcer prevention care bundle. Of 799 intervention patients in the trial, 96.7% received the intervention, which took under 10 min to deliver. Patients and nurses accepted the care bundle, recognising benefits to it and describing how it enabled participation in pressure ulcer prevention (PUP) care. This process evaluation found no major failures

Educational outreach to general practitioners reduces children's asthma symptoms: a cluster randomised controlled trial

Directory of Open Access Journals (Sweden)

Sladden Michael

2007-09-01

Full Text Available Abstract Background Childhood asthma is common in Cape Town, a province of South Africa, but is underdiagnosed by general practitioners. Medications are often prescribed inappropriately, and care is episodic. The objective of this study is to assess the impact of educational outreach to general practitioners on asthma symptoms of children in their practice. Methods This is a cluster randomised trial with general practices as the unit of intervention, randomisation, and analysis. The setting is Mitchells Plain (population 300,000, a dormitory town near Cape Town. Solo general practitioners, without nurse support, operate from storefront practices. Caregiver-reported symptom data were collected for 318 eligible children (2 to 17 years with moderate to severe asthma, who were attending general practitioners in Mitchells Plain. One year post-intervention follow-up data were collected for 271 (85% of these children in all 43 practices. Practices randomised to intervention (21 received two 30-minute educational outreach visits by a trained pharmacist who left materials describing key interventions to improve asthma care. Intervention and control practices received the national childhood asthma guideline. Asthma severity was measured in a parent-completed survey administered through schools using a symptom frequency and severity scale. We compared intervention and control group children on the change in score from pre-to one-year post-intervention. Results Symptom scores declined an additional 0.84 points in the intervention vs. control group (on a nine-point scale. p = 0.03. For every 12 children with asthma exposed to a doctor allocated to the intervention, one extra child will have substantially reduced symptoms. Conclusion Educational outreach was accepted by general practitioners and was effective. It could be applied to other health care quality problems in this setting.

Effect on the process of care of an active strategy to implement clinical guidelines on physiotherapy for low back pain: a cluster randomised controlled trial

NARCIS (Netherlands)

Bekkering, G.E.; Hendriks, H.J.M.; Tulder, van M.; Knol, D.L.; Hoeijenbos, M.; Oostendorp, R.A.B.; Bouter, L.M.

2005-01-01

OBJECTIVES: To evaluate the effect on the process of care of an active strategy to implement clinical guidelines on physiotherapy for low back pain. DESIGN: A cluster randomised controlled trial comparing an active strategy with standard dissemination. SETTING: Primary care physiotherapy practices.

Metabolic manipulation in chronic heart failure: study protocol for a randomised controlled trial

Directory of Open Access Journals (Sweden)

Leon Francisco

2011-06-01

Full Text Available Abstract Background Heart failure is a major cause of morbidity and mortality in society. Current medical therapy centres on neurohormonal modulation with angiotensin converting enzyme inhibitors and β-blockers. There is growing evidence for the use of metabolic manipulating agents as adjunctive therapy in patients with heart failure. We aim to determine the effect of perhexiline on cardiac energetics and alterations in substrate utilisation in patients with non-ischaemic dilated cardiomyopathy. Methods A multi-centre, prospective, randomised double-blind, placebo-controlled trial of 50 subjects with non-ischaemic dilated cardiomyopathy recruited from University Hospital Birmingham NHS Foundation Trust and Cardiff and Vale NHS Trust. Baseline investigations include magnetic resonance spectroscopy to assess cardiac energetic status, echocardiography to assess left ventricular function and assessment of symptomatic status. Subjects are then randomised to receive 200 mg perhexiline maleate or placebo daily for 4 weeks with serum drug level monitoring. All baseline investigations will be repeated at the end of the treatment period. A subgroup of patients will undergo invasive investigations with right and left heart catheterisation to calculate respiratory quotient, and mechanical efficiency. The primary endpoint is an improvement in the phosphocreatine to adenosine triphosphate ratio at 4 weeks. Secondary end points are: i respiratory quotient; ii mechanical efficiency; iii change in left ventricular (LV function. Trial Registration ClinicalTrials.gov: NCT00841139 ISRCTN: ISRCTN2887836

The Effects of Skill Training on Social Workers' Professional Competences in Norway: Results of a Cluster-Randomised Study

Science.gov (United States)

Malmberg-Heimonen, Ira; Natland, Sidsel; Tøge, Anne Grete; Hansen, Helle Cathrine

2016-01-01

Using a cluster-randomised design, this study analyses the effects of a government-administered skill training programme for social workers in Norway. The training programme aims to improve social workers' professional competences by enhancing and systematising follow-up work directed towards longer-term unemployed clients in the following areas: encountering the user, system-oriented efforts and administrative work. The main tools and techniques of the programme are based on motivational interviewing and appreciative inquiry. The data comprise responses to baseline and eighteen-month follow-up questionnaires administered to all social workers (n = 99) in eighteen participating Labour and Welfare offices randomised into experimental and control groups. The findings indicate that the skill training programme positively affected the social workers' evaluations of their professional competences and quality of work supervision received. The acquisition and mastering of combinations of specific tools and techniques, a comprehensive supervision structure and the opportunity to adapt the learned skills to local conditions were important in explaining the results. PMID:27559232

Multi-cellular natural killer (NK) cell clusters enhance NK cell activation through localizing IL-2 within the cluster

Science.gov (United States)

Kim, Miju; Kim, Tae-Jin; Kim, Hye Mi; Doh, Junsang; Lee, Kyung-Mi

2017-01-01

Multi-cellular cluster formation of natural killer (NK) cells occurs during in vivo priming and potentiates their activation to IL-2. However, the precise mechanism underlying this synergy within NK cell clusters remains unclear. We employed lymphocyte-laden microwell technologies to modulate contact-mediated multi-cellular interactions among activating NK cells and to quantitatively assess the molecular events occurring in multi-cellular clusters of NK cells. NK cells in social microwells, which allow cell-to-cell contact, exhibited significantly higher levels of IL-2 receptor (IL-2R) signaling compared with those in lonesome microwells, which prevent intercellular contact. Further, CD25, an IL-2R α chain, and lytic granules of NK cells in social microwells were polarized toward MTOC. Live cell imaging of lytic granules revealed their dynamic and prolonged polarization toward neighboring NK cells without degranulation. These results suggest that IL-2 bound on CD25 of one NK cells triggered IL-2 signaling of neighboring NK cells. These results were further corroborated by findings that CD25-KO NK cells exhibited lower proliferation than WT NK cells, and when mixed with WT NK cells, underwent significantly higher level of proliferation. These data highlights the existence of IL-2 trans-presentation between NK cells in the local microenvironment where the availability of IL-2 is limited.

Effect of the daily consumption of protein enriched bread and protein enriched drinking yoghurt on the total protein intake in older adults in a rehabilitation centre: a single blind randomised controlled trial

NARCIS (Netherlands)

Til, van A.J.; Naumann, E.; Cox-Claessens, I.J.H.M.; Kremer, S.; Boelsma, E.; Schueren, van der D.E.

2015-01-01

Objectives To investigate the effects of protein enriched bread and drinking yoghurt, substituting regular products, on the total protein intake and the distribution of protein intake over the day in older adults. Design A single blind randomised controlled trial. Setting Rehabilitation centre.

The impact of a disease management program (COACH) on the attainment of better cardiovascular risk control in dyslipidaemic patients at primary care centres (The DISSEMINATE Study): a randomised controlled trial.

Science.gov (United States)

Selvaraj, Francis Jude; Mohamed, Mafauzy; Omar, Khairani; Nanthan, Sudha; Kusiar, Zainab; Subramaniam, Selvaraj Y; Ali, Norsiah; Karanakaran, Kamalakaran; Ahmad, Fauziah; Low, Wilson H H

2012-10-10

To evaluate the efficacy of Counselling and Advisory Care for Health (COACH) programme in managing dyslipidaemia among primary care practices in Malaysia. This open-label, parallel, randomised controlled trial compared the COACH programme delivered by primary care physicians alone (PCP arm) and primary care physicians assisted by nurse educators (PCP-NE arm). This was a multi-centre, open label, randomised trial of a disease management programme (COACH) among dyslipidaemic patients in 21 Malaysia primary care practices. The participating centres enrolled 297 treatment naïve subjects who had the primary diagnosis of dyslipidaemia; 149 were randomised to the COACH programme delivered by primary care physicians assisted by nurse educators (PCP-NE) and 148 to care provided by primary care physicians (PCP) alone. The primary efficacy endpoint was the mean percentage change from baseline LDL-C at week 24 between the 2 study arms. Secondary endpoints included mean percentage change from baseline of lipid profile (TC, LDL-C, HDL-C, TG, TC: HDL ratio), Framingham Cardiovascular Health Risk Score and absolute risk change from baseline in blood pressure parameters at week 24. The study also assessed the sustainability of programme efficacy at week 36. Both study arms demonstrated improvement in LDL-C from baseline. The least squares (LS) mean change from baseline LDL-C were -30.09% and -27.54% for PCP-NE and PCP respectively. The difference in mean change between groups was 2.55% (p=0.288), with a greater change seen in the PCP-NE arm. Similar observations were made between the study groups in relation to total cholesterol change at week 24. Significant difference in percentage change from baseline of HDL-C were observed between the PCP-NE and PCP groups, 3.01%, 95% CI 0.12-5.90, p=0.041, at week 24. There was no significant difference in lipid outcomes between 2 study groups at week 36 (12 weeks after the programme had ended). Patients who received coaching and advice from

Falls prevention and balance rehabilitation in multiple sclerosis: a bi-centre randomised controlled trial.

Science.gov (United States)

Cattaneo, Davide; Rasova, Kamila; Gervasoni, Elisa; Dobrovodská, Gabriela; Montesano, Angelo; Jonsdottir, Johanna

2018-03-01

People with Multiple Sclerosis (PwMS) have a high incidence of accidental falls that have a potentially detrimental effect on their daily life participation. The effect of balance specific rehabilitation on clinical balance measures and frequency of falls in PwMS was studied. A bi-centre randomised rater-blinded controlled trial. Participants in both groups received 20 treatment sessions. Participants in the intervention group received treatment aimed at improving balance and mobility. Participants in the control group received treatments to reduce limitations at activity and body function level. Primary measures were frequency of fallers (>1 fall in two months) and responders (>3 points improvement) at the Berg Balance Scale (BBS). Data was analysed according to an intention to treat approach. One hundred and nineteen participants were randomised. Following treatment frequency of fallers was 22% in the intervention group and 23% in the control group, odds ratio (OR) and (confidence limits): 1.05 (0.41 to 2.77). Responders on the BBS were 28% in the intervention group and 33% in the control group, OR = 0.75 (0.30 to 1.91). At follow up ORs for fallers and responders at BBS were 0.98 (0.48 to 2.01) and 0.79 (0.26 to 2.42), respectively. Twenty sessions 2-3 times/week of balance specific rehabilitation did not reduce fall frequency nor improve balance suggesting the need for more frequent and challenging interventions. Implications for Rehabilitation Programs for balance rehabilitation can improve balance but their effects in fall prevention are unclear. Twenty treatments sessions 2/3 times per week did not reduced frequency of falls in MS. The comparison with similar studies suggests that higher intensity of practice of highly challenging balance activities appears to be critical to maximizing effectiveness.

Feasibility and acceptability of training community health workers in ear and hearing care in Malawi: a cluster randomised controlled trial.

Science.gov (United States)

Mulwafu, Wakisa; Kuper, Hannah; Viste, Asgaut; Goplen, Frederik K

2017-10-11

To assess the feasibility and acceptability of training community health workers (CHWs) in ear and hearing care, and their ability to identify patients with ear and hearing disorders. Cluster randomised controlled trial (RCT). Health centres in Thyolo district, Malawi. Ten health centres participated, 5 intervention (29 CHWs) and 5 control (28 CHWs). Intervention CHWs received 3 days of training in primary ear and hearing care, while among control CHWs, training was delayed for 6 months. Both groups were given a pretest that assessed knowledge about ear and hearing care, only the intervention group was given the posttest on the third day of training. The intervention group was given 1 month to identify patients with ear and hearing disorders in their communities, and these people were screened for hearing disorders by ear, nose and throat clinical specialists. Primary outcome measure was improvement in knowledge of ear and hearing care among CHWs after the training. Secondary outcome measures were number of patients with ear or hearing disorders identified by CHWs and number recorded at health centres during routine activities, and the perceived feasibility and acceptability of the intervention. The average overall correct answers increased from 55% to 68% (95% CI 65 to 71) in the intervention group (phearing disorders were identified by CHWs and 860 patients attended the screening camps, of whom 400 had hearing loss (73 patients determined through bilateral fail on otoacoustic emissions, 327 patients through audiometry). Where cause could be determined, the most common cause of ear and hearing disorders was chronic suppurative otitis media followed by impacted wax. The intervention was perceived as feasible and acceptable to implement. Training was effective in improving the knowledge of CHW in ear and hearing care in Malawi and allowing them to identify patients with ear and hearing disorders. This intervention could be scaled up to other CHWs in low-income and

From superdeformation to clusters

Energy Technology Data Exchange (ETDEWEB)

Betts, R R [Argonne National Lab., IL (United States). Physics Div.

1992-08-01

Much of the discussion at the conference centred on superdeformed states and their study by precise gamma spectrometry. The author suggests that the study of superdeformation by fission fragments and by auto-scattering is of importance, and may become more important. He concludes that there exists clear evidence of shell effects at extreme deformation in light nuclei studied by fission or cluster decay. The connection between the deformed shell model and the multi-center shell model can be exploited to give give insight into the cluster structure of these extremely deformed states, and also gives hope of a spectroscopy based on selection rules for cluster decay. A clear disadvantage at this stage is inability to make this spectroscopy more quantitative through calculation of the decay widths. The introduction of a new generation of high segmentation, high resolution, particle arrays has and will have a major impact on this aspect of the study of highly deformed nuclei. 20 refs., 16 figs.

A pragmatic cluster randomised controlled trial to evaluate the safety, clinical effectiveness, cost effectiveness and satisfaction with point of care testing in a general practice setting - rationale, design and baseline characteristics.

Science.gov (United States)

Laurence, Caroline; Gialamas, Angela; Yelland, Lisa; Bubner, Tanya; Ryan, Philip; Willson, Kristyn; Glastonbury, Briony; Gill, Janice; Shephard, Mark; Beilby, Justin

2008-08-06

Point of care testing (PoCT) may be a useful adjunct in the management of chronic conditions in general practice (GP). The provision of pathology test results at the time of the consultation could lead to enhanced clinical management, better health outcomes, greater convenience and satisfaction for patients and general practitioners (GPs), and savings in costs and time. It could also result in inappropriate testing, increased consultations and poor health outcomes resulting from inaccurate results. Currently there are very few randomised controlled trials (RCTs) in GP that have investigated these aspects of PoCT. The Point of Care Testing in General Practice Trial (PoCT Trial) was an Australian Government funded multi-centre, cluster randomised controlled trial to determine the safety, clinical effectiveness, cost effectiveness and satisfaction of PoCT in a GP setting.The PoCT Trial covered an 18 month period with the intervention consisting of the use of PoCT for seven tests used in the management of patients with diabetes, hyperlipidaemia and patients on anticoagulant therapy. The primary outcome measure was the proportion of patients within target range, a measure of therapeutic control. In addition, the PoCT Trial investigated the safety of PoCT, impact of PoCT on patient compliance to medication, stakeholder satisfaction, cost effectiveness of PoCT versus laboratory testing, and influence of geographic location. The paper provides an overview of the Trial Design, the rationale for the research methodology chosen and how the Trial was implemented in a GP environment. The evaluation protocol and data collection processes took into account the large number of patients, the broad range of practice types distributed over a large geographic area, and the inclusion of pathology test results from multiple pathology laboratories.The evaluation protocol developed reflects the complexity of the Trial setting, the Trial Design and the approach taken within the funding

Change in cardiovascular risk factors following early diagnosis of type 2 diabetes: a cohort analysis of a cluster-randomised trial

OpenAIRE

Black, James A; Sharp, Stephen J; Wareham, Nicholas J; Sandbæk, Annelli; Rutten, Guy EHM; Lauritzen, Torsten; Khunti, Kamlesh; Davies, Melanie J; Borch-Johnsen, Knut; Griffin, Simon J; Simmons, Rebecca K

2014-01-01

Background There is little evidence to inform the targeted treatment of individuals found early in the diabetes disease trajectory. Aim To describe cardiovascular disease (CVD) risk profiles and treatment of individual CVD risk factors by modelled CVD risk at diagnosis; changes in treatment, modelled CVD risk, and CVD risk factors in the 5 years following diagnosis; and how these are patterned by socioeconomic status. Design and setting Cohort analysis of a cluster-randomised trial (ADDITION-...

Changes in body weight and food choice in those attempting smoking cessation: a cluster randomised controlled trial

Directory of Open Access Journals (Sweden)

Leslie Wilma S

2012-05-01

Full Text Available Abstract Background Fear of weight gain is a barrier to smoking cessation and significant cause of relapse for many people. The provision of nutritional advice as part of a smoking cessation programme may assist some in smoking cessation and perhaps limit weight gain. The aim of this study was to determine the effect of a structured programme of dietary advice on weight change and food choice, in adults attempting smoking cessation. Methods Cluster randomised controlled design. Classes randomised to intervention commenced a 24-week intervention, focussed on improving food choice and minimising weight gain. Classes randomised to control received “usual care”. Results Twenty-seven classes in Greater Glasgow were randomised between January and August 2008. Analysis, including those who continued to smoke, showed that actual weight gain and percentage weight gain was similar in both groups. Examination of data for those successful at giving up smoking showed greater mean weight gain in intervention subjects (3.9 (SD 3.1 vs. 2.7 (SD 3.7 kg. Between group differences were not significant (p = 0.23, 95% CI −0.9 to 3.5. In comparison to baseline improved consumption of fruit and vegetables and breakfast cereal were reported in the intervention group. A higher percentage of control participants continued smoking (74% vs. 66%. Conclusions The intervention was not successful at minimising weight gain in comparison to control but was successful in facilitating some sustained improvements in the dietary habits of intervention participants. Improved quit rates in the intervention group suggest that continued contact with advisors may have reduced anxieties regarding weight gain and encouraged cessation despite weight gain. Research should continue in this area as evidence suggests that the negative effects of obesity could outweigh the health benefits achieved through reductions in smoking prevalence. Trial registration Current Controlled Trials

Multi-conjugate adaptive optics observations of the Orion Trapezium Cluster

International Nuclear Information System (INIS)

Petr-Gotzens, M G; Kolb, J; Marchetti, E; Sterzik, M F; Ivanov, V D; Nuernberger, D; Koehler, R; Bouy, H; MartIn, E L; Huelamo, N; Navascues, D Barrado y

2008-01-01

We obtained very deep and high spatial resolution near-infrared images of the Orion Trapezium Cluster using the Multi-Conjugate Adaptive Optics Demonstrator (MAD) instrument at the VLT. The goal of these observations has been to search for objects at the very low-mass end of the IMF down to the planetary-mass regime. Three fields in the innermost dense part of the Trapezium Cluster, with a total area of 3.5 sq.arcmin have been surveyed at 1.65μm and 2.2μm. Several new candidate planetary mass objects with potential masses Jup have been detected based on their photometry and on their location in the colour-magnitude diagram. The performance of the multi-conjugate adaptive optics correction is excellent over a large field-of-view of ∼ 1'. The final data has a spatial resolution of Jup ), however, must await future confirmation by spectroscopic and/or photometric observations.

Menstrual cups and sanitary pads to reduce school attrition, and sexually transmitted and reproductive tract infections: a cluster randomised controlled feasibility study in rural Western Kenya

NARCIS (Netherlands)

Phillips-Howard, Penelope A.; Nyothach, Elizabeth; ter Kuile, Feiko O.; Omoto, Jackton; Wang, Duolao; Zeh, Clement; Onyango, Clayton; Mason, Linda; Alexander, Kelly T.; Odhiambo, Frank O.; Eleveld, Alie; Mohammed, Aisha; van Eijk, Anna M.; Edwards, Rhiannon Tudor; Vulule, John; Faragher, Brian; Laserson, Kayla F.

2016-01-01

Conduct a feasibility study on the effect of menstrual hygiene on schoolgirls' school and health (reproductive/sexual) outcomes. 3-arm single-site open cluster randomised controlled pilot study. 30 primary schools in rural western Kenya, within a Health and Demographic Surveillance System. Primary

Non-extensive statistical aspects of clustering and nuclear multi-fragmentation

International Nuclear Information System (INIS)

Calboreanu, A.

2002-01-01

Recent developments concerning an application of the non-extensive Tsalis statistics to describe clustering phenomena is briefly presented. Cluster formation is a common feature of a large number of physical phenomena encountered in molecular and nuclear physics, astrophysics, condensed matter and biophysics. Common to all these is the large number of degrees of freedom, thus justifying a statistical approach. However the conventional statistical mechanics paradigm seems to fail in dealing with clustering. Whether this is due to the prevalence of complex dynamical constrains, or it is a manifestation of new statistics is a subject of considerable interest, which was intensively debated during the last few years. Tsalis conjecture has proved extremely appealing due to its rather elegant and transparent basic arguments. We present here evidence for its adequacy for the study of a large class of physical phenomena related to cluster formation. An application to nuclear multi-fragmentation is presented. (author)

A Dimensionality Reduction-Based Multi-Step Clustering Method for Robust Vessel Trajectory Analysis

Directory of Open Access Journals (Sweden)

Huanhuan Li

2017-08-01

Full Text Available The Shipboard Automatic Identification System (AIS is crucial for navigation safety and maritime surveillance, data mining and pattern analysis of AIS information have attracted considerable attention in terms of both basic research and practical applications. Clustering of spatio-temporal AIS trajectories can be used to identify abnormal patterns and mine customary route data for transportation safety. Thus, the capacities of navigation safety and maritime traffic monitoring could be enhanced correspondingly. However, trajectory clustering is often sensitive to undesirable outliers and is essentially more complex compared with traditional point clustering. To overcome this limitation, a multi-step trajectory clustering method is proposed in this paper for robust AIS trajectory clustering. In particular, the Dynamic Time Warping (DTW, a similarity measurement method, is introduced in the first step to measure the distances between different trajectories. The calculated distances, inversely proportional to the similarities, constitute a distance matrix in the second step. Furthermore, as a widely-used dimensional reduction method, Principal Component Analysis (PCA is exploited to decompose the obtained distance matrix. In particular, the top k principal components with above 95% accumulative contribution rate are extracted by PCA, and the number of the centers k is chosen. The k centers are found by the improved center automatically selection algorithm. In the last step, the improved center clustering algorithm with k clusters is implemented on the distance matrix to achieve the final AIS trajectory clustering results. In order to improve the accuracy of the proposed multi-step clustering algorithm, an automatic algorithm for choosing the k clusters is developed according to the similarity distance. Numerous experiments on realistic AIS trajectory datasets in the bridge area waterway and Mississippi River have been implemented to compare our

A Dimensionality Reduction-Based Multi-Step Clustering Method for Robust Vessel Trajectory Analysis.

Science.gov (United States)

Li, Huanhuan; Liu, Jingxian; Liu, Ryan Wen; Xiong, Naixue; Wu, Kefeng; Kim, Tai-Hoon

2017-08-04

The Shipboard Automatic Identification System (AIS) is crucial for navigation safety and maritime surveillance, data mining and pattern analysis of AIS information have attracted considerable attention in terms of both basic research and practical applications. Clustering of spatio-temporal AIS trajectories can be used to identify abnormal patterns and mine customary route data for transportation safety. Thus, the capacities of navigation safety and maritime traffic monitoring could be enhanced correspondingly. However, trajectory clustering is often sensitive to undesirable outliers and is essentially more complex compared with traditional point clustering. To overcome this limitation, a multi-step trajectory clustering method is proposed in this paper for robust AIS trajectory clustering. In particular, the Dynamic Time Warping (DTW), a similarity measurement method, is introduced in the first step to measure the distances between different trajectories. The calculated distances, inversely proportional to the similarities, constitute a distance matrix in the second step. Furthermore, as a widely-used dimensional reduction method, Principal Component Analysis (PCA) is exploited to decompose the obtained distance matrix. In particular, the top k principal components with above 95% accumulative contribution rate are extracted by PCA, and the number of the centers k is chosen. The k centers are found by the improved center automatically selection algorithm. In the last step, the improved center clustering algorithm with k clusters is implemented on the distance matrix to achieve the final AIS trajectory clustering results. In order to improve the accuracy of the proposed multi-step clustering algorithm, an automatic algorithm for choosing the k clusters is developed according to the similarity distance. Numerous experiments on realistic AIS trajectory datasets in the bridge area waterway and Mississippi River have been implemented to compare our proposed method with

Meta Salud Diabetes study protocol: a cluster-randomised trial to reduce cardiovascular risk among a diabetic population of Mexico

Science.gov (United States)

Cornejo Vucovich, Elsa; Ingram, Maia; Valenica, Celina; Castro Vasquez, Maria del Carmen; Gonzalez-Fagoaga, Eduardo; Geurnsey de Zapien, Jill

2018-01-01

Introduction Northern Mexico has among the highest rates of cardiovascular disease (CVD) and diabetes in the world. This research addresses core gaps in implementation science to develop, test and scale-up CVD risk-reduction interventions in diabetics through a national primary care health system. Methods and analysis The Meta Salud Diabetes (MSD) research project is a parallel two-arm cluster-randomised clinical behavioural trial based in 22 (n=22) health centres in Sonora, Mexico. MSD aims to evaluate the effectiveness of the MSD intervention for the secondary prevention of CVD risk factors among a diabetic population (n=320) compared with the study control of usual care. The MSD intervention consists of 2-hour class sessions delivered over a 13-week period providing educational information to encourage sustainable behavioural change to prevent disease complications including the adoption of physical activity. MSD is delivered within the context of Mexico’s national primary care health centre system by health professionals, including nurses, physicians and community health workers via existing social support groups for individuals diagnosed with chronic disease. Mixed models are used to estimate the effect of MSD by comparing cardiovascular risk, as measured by the Framingham Risk Score, between the trial arms. Secondary outcomes include hypertension, behavioural risk factors and psychosocial factors. Ethics and dissemination This work is supported by the National Institutes of Health, National Heart Lung and Blood Institute (1R01HL125996-01) and approved by the University of Arizona Research Institutional Review Board (Protocol 1508040144) and the Research Bioethics Committee at the University of Sonora. The first Internal Review Board approval date was 31 August 2015 with five subsequent approved amendments. This article refers to protocol V.0.2, dated 30 January 2017. Results will be disseminated via peer-reviewed publication and presentation at

Meta Salud Diabetes study protocol: a cluster-randomised trial to reduce cardiovascular risk among a diabetic population of Mexico.

Science.gov (United States)

Sabo, Samantha; Denman Champion, Catalina; Bell, Melanie L; Cornejo Vucovich, Elsa; Ingram, Maia; Valenica, Celina; Castro Vasquez, Maria Del Carmen; Gonzalez-Fagoaga, Eduardo; Geurnsey de Zapien, Jill; Rosales, Cecilia B

2018-03-12

Northern Mexico has among the highest rates of cardiovascular disease (CVD) and diabetes in the world. This research addresses core gaps in implementation science to develop, test and scale-up CVD risk-reduction interventions in diabetics through a national primary care health system. The Meta Salud Diabetes (MSD) research project is a parallel two-arm cluster-randomised clinical behavioural trial based in 22 (n=22) health centres in Sonora, Mexico. MSD aims to evaluate the effectiveness of the MSD intervention for the secondary prevention of CVD risk factors among a diabetic population (n=320) compared with the study control of usual care. The MSD intervention consists of 2-hour class sessions delivered over a 13-week period providing educational information to encourage sustainable behavioural change to prevent disease complications including the adoption of physical activity. MSD is delivered within the context of Mexico's national primary care health centre system by health professionals, including nurses, physicians and community health workers via existing social support groups for individuals diagnosed with chronic disease. Mixed models are used to estimate the effect of MSD by comparing cardiovascular risk, as measured by the Framingham Risk Score, between the trial arms. Secondary outcomes include hypertension, behavioural risk factors and psychosocial factors. This work is supported by the National Institutes of Health, National Heart Lung and Blood Institute (1R01HL125996-01) and approved by the University of Arizona Research Institutional Review Board (Protocol 1508040144) and the Research Bioethics Committee at the University of Sonora. The first Internal Review Board approval date was 31 August 2015 with five subsequent approved amendments. This article refers to protocol V.0.2, dated 30 January 2017. Results will be disseminated via peer-reviewed publication and presentation at international conferences and will be shared through meetings with health

Use of malaria rapid diagnostic tests by community health workers in Afghanistan: cluster randomised trial.

Science.gov (United States)

Leslie, Toby; Rowland, Mark; Mikhail, Amy; Cundill, Bonnie; Willey, Barbara; Alokozai, Asif; Mayan, Ismail; Hasanzai, Anwar; Baktash, Sayed Habibullah; Mohammed, Nader; Wood, Molly; Rahimi, Habib-U-Rahman; Laurent, Baptiste; Buhler, Cyril; Whitty, Christopher J M

2017-07-07

The World Health Organisation (WHO) recommends parasitological diagnosis of malaria before treatment, but use of malaria rapid diagnostic tests (mRDTs) by community health workers (CHWs) has not been fully tested within health services in south and central Asia. mRDTs could allow CHWs to diagnose malaria accurately, improving treatment of febrile illness. A cluster randomised trial in community health services was undertaken in Afghanistan. The primary outcome was the proportion of suspected malaria cases correctly treated for polymerase chain reaction (PCR)-confirmed malaria and PCR negative cases receiving no antimalarial drugs measured at the level of the patient. CHWs from 22 clusters (clinics) received standard training on clinical diagnosis and treatment of malaria; 11 clusters randomised to the intervention arm received additional training and were provided with mRDTs. CHWs enrolled cases of suspected malaria, and the mRDT results and treatments were compared to blind-read PCR diagnosis. In total, 256 CHWs enrolled 2400 patients with 2154 (89.8%) evaluated. In the intervention arm, 75.3% (828/1099) were treated appropriately vs. 17.5% (185/1055) in the control arm (cluster adjusted risk ratio: 3.72, 95% confidence interval 2.40-5.77; p < 0.001). In the control arm, 85.9% (164/191) with confirmed Plasmodium vivax received chloroquine compared to 45.1% (70/155) in the intervention arm (p < 0.001). Overuse of chloroquine in the control arm resulted in 87.6% (813/928) of those with no malaria (PCR negative) being treated vs. 10.0% (95/947) in the intervention arm, p < 0.001. In the intervention arm, 71.4% (30/42) of patients with P. falciparum did not receive artemisinin-based combination therapy, partly because operational sensitivity of the RDTs was low (53.2%, 38.1-67.9). There was high concordance between recorded RDT result and CHW prescription decisions: 826/950 (87.0%) with a negative test were not prescribed an antimalarial. Co

REFOCUS Trial: protocol for a cluster randomised controlled trial of a pro-recovery intervention within community based mental health teams

Directory of Open Access Journals (Sweden)

Slade Mike

2011-11-01

Full Text Available Abstract Background There is a consensus about the importance of 'recovery' in mental health services, but the evidence base is limited. Methods/Design A two centre, cluster randomised controlled trial. Participants are community-based mental health teams, and service users aged 18-65 years with a primary clinical diagnosis of psychosis. In relation to the REFOCUS Manual researchintorecovery.com/refocus, which describes a 12-month, pro-recovery intervention based on the REFOCUS Model, the objectives are: (1 To establish the effectiveness of the intervention described in the REFOCUS Manual; (2 To validate the REFOCUS Model; (3 To establish and optimise trial parameters for the REFOCUS Manual; and (4 To understand the relationship between clinical outcomes and recovery outcomes. The hypothesis for the main study is that service users in the intervention arm will experience significantly greater increases in measures of personal recovery (as measured by the QPR compared to service users receiving care from control teams. The hypothesis for the secondary study is that black service users in the intervention arm will experience significantly greater increases in measures of personal recovery (as measured by the QPR and client satisfaction (as measured by the CSQ compared to Black service users receiving care from control teams. The intervention comprises treatment as usual plus two components: recovery-promoting relationships and working practices. The control condition is treatment as usual. The primary outcme is the Process of Recovery Questionnaire (QPR. Secondary outcomes are satisfaction, Goal setting - Personal Primary Outcome, hope, well-being, empowerment, and quality of life. Primary outcomes for the secondary study will be QPR and satisfaction. Cost data will be estimated, and clinical outcomes will also be reported (symptomatology, need, social disability, functioning. 29 teams (15 intervention and 14 control will be randomised. Within

SU(3) techniques for angular momentum projected matrix elements in multi-cluster problems

International Nuclear Information System (INIS)

Hecht, K.T.; Zahn, W.

1978-01-01

In the theory of integral transforms for the evaluation of the resonating group kernels needed for cluster model calculations, the evaluation of matrix elements in an angular momentum coupled basis has proved to be difficult for cluster problems involving more than two fragments. For multi-cluster wave functions SU(3) coupling and recoupling techniques can furnish a tool for the practical evaluation matrix elements in an angular momentum coupled basis if the several relative motion harmonic oscillator functions in Bargmann space have simple SU(3) coupling properties. The method is illustrated by a three-cluster problem, such as 12 C = α + α + α, involving three 1 S clusters. 2 references

Patch: platelet transfusion in cerebral haemorrhage: study protocol for a multicentre, randomised, controlled trial

Directory of Open Access Journals (Sweden)

Dijkgraaf Marcel G

2010-03-01

Full Text Available Abstract Background Patients suffering from intracerebral haemorrhage have a poor prognosis, especially if they are using antiplatelet therapy. Currently, no effective acute treatment option for intracerebral haemorrhage exists. Limiting the early growth of intracerebral haemorrhage volume which continues the first hours after admission seems a promising strategy. Because intracerebral haemorrhage patients who are on antiplatelet therapy have been shown to be particularly at risk of early haematoma growth, platelet transfusion may have a beneficial effect. Methods/Design The primary objective is to investigate whether platelet transfusion improves outcome in intracerebral haemorrhage patients who are on antiplatelet treatment. The PATCH study is a prospective, randomised, multi-centre study with open treatment and blind endpoint evaluation. Patients will be randomised to receive platelet transfusion within six hours or standard care. The primary endpoint is functional health after three months. The main secondary endpoints are safety of platelet transfusion and the occurrence of haematoma growth. To detect an absolute poor outcome reduction of 20%, a total of 190 patients will be included. Discussion To our knowledge this is the first randomised controlled trial of platelet transfusion for an acute haemorrhagic disease. Trial registration The Netherlands National Trial Register (NTR1303

SLA-based optimisation of virtualised resource for multi-tier web applications in cloud data centres

Science.gov (United States)

Bi, Jing; Yuan, Haitao; Tie, Ming; Tan, Wei

2015-10-01

Dynamic virtualised resource allocation is the key to quality of service assurance for multi-tier web application services in cloud data centre. In this paper, we develop a self-management architecture of cloud data centres with virtualisation mechanism for multi-tier web application services. Based on this architecture, we establish a flexible hybrid queueing model to determine the amount of virtual machines for each tier of virtualised application service environments. Besides, we propose a non-linear constrained optimisation problem with restrictions defined in service level agreement. Furthermore, we develop a heuristic mixed optimisation algorithm to maximise the profit of cloud infrastructure providers, and to meet performance requirements from different clients as well. Finally, we compare the effectiveness of our dynamic allocation strategy with two other allocation strategies. The simulation results show that the proposed resource allocation method is efficient in improving the overall performance and reducing the resource energy cost.

A pragmatic cluster randomised controlled trial to evaluate the safety, clinical effectiveness, cost effectiveness and satisfaction with point of care testing in a general practice setting – rationale, design and baseline characteristics

Directory of Open Access Journals (Sweden)

Glastonbury Briony

2008-08-01

Full Text Available Abstract Background Point of care testing (PoCT may be a useful adjunct in the management of chronic conditions in general practice (GP. The provision of pathology test results at the time of the consultation could lead to enhanced clinical management, better health outcomes, greater convenience and satisfaction for patients and general practitioners (GPs, and savings in costs and time. It could also result in inappropriate testing, increased consultations and poor health outcomes resulting from inaccurate results. Currently there are very few randomised controlled trials (RCTs in GP that have investigated these aspects of PoCT. Design/Methods The Point of Care Testing in General Practice Trial (PoCT Trial was an Australian Government funded multi-centre, cluster randomised controlled trial to determine the safety, clinical effectiveness, cost effectiveness and satisfaction of PoCT in a GP setting. The PoCT Trial covered an 18 month period with the intervention consisting of the use of PoCT for seven tests used in the management of patients with diabetes, hyperlipidaemia and patients on anticoagulant therapy. The primary outcome measure was the proportion of patients within target range, a measure of therapeutic control. In addition, the PoCT Trial investigated the safety of PoCT, impact of PoCT on patient compliance to medication, stakeholder satisfaction, cost effectiveness of PoCT versus laboratory testing, and influence of geographic location. Discussion The paper provides an overview of the Trial Design, the rationale for the research methodology chosen and how the Trial was implemented in a GP environment. The evaluation protocol and data collection processes took into account the large number of patients, the broad range of practice types distributed over a large geographic area, and the inclusion of pathology test results from multiple pathology laboratories. The evaluation protocol developed reflects the complexity of the Trial setting

Improving person-centred care in nursing homes through dementia-care mapping: design of a cluster-randomised controlled trial.

NARCIS (Netherlands)

Ven, G. van de; Draskovic, I.; Adang, E.M.M.; Donders, R.; Post, A.; Zuidema, S.U.; Koopmans, R.T.C.M.; Vernooij-Dassen, M.J.F.J.

2012-01-01

BACKGROUND: The effectiveness and efficiency of nursing-home dementia care are suboptimal: there are high rates of neuropsychiatric symptoms among the residents and work-related stress among the staff. Dementia-care mapping is a person-centred care method that may alleviate both the resident and the

Evidence-based care of older people with suspected cognitive impairment in general practice: protocol for the IRIS cluster randomised trial.

Science.gov (United States)

McKenzie, Joanne E; French, Simon D; O'Connor, Denise A; Mortimer, Duncan S; Browning, Colette J; Russell, Grant M; Grimshaw, Jeremy M; Eccles, Martin P; Francis, Jill J; Michie, Susan; Murphy, Kerry; Kossenas, Fiona; Green, Sally E

2013-08-19

Dementia is a common and complex condition. Evidence-based guidelines for the management of people with dementia in general practice exist; however, detection, diagnosis and disclosure of dementia have been identified as potential evidence-practice gaps. Interventions to implement guidelines into practice have had varying success. The use of theory in designing implementation interventions has been limited, but is advocated because of its potential to yield more effective interventions and aid understanding of factors modifying the magnitude of intervention effects across trials. This protocol describes methods of a randomised trial that tests a theory-informed implementation intervention that, if effective, may provide benefits for patients with dementia and their carers. This trial aims to estimate the effectiveness of a theory-informed intervention to increase GPs' (in Victoria, Australia) adherence to a clinical guideline for the detection, diagnosis, and management of dementia in general practice, compared with providing GPs with a printed copy of the guideline. Primary objectives include testing if the intervention is effective in increasing the percentage of patients with suspected cognitive impairment who receive care consistent with two key guideline recommendations: receipt of a i) formal cognitive assessment, and ii) depression assessment using a validated scale (primary outcomes for the trial). The design is a parallel cluster randomised trial, with clusters being general practices. We aim to recruit 60 practices per group. Practices will be randomised to the intervention and control groups using restricted randomisation. Patients meeting the inclusion criteria, and GPs' detection and diagnosis behaviours directed toward these patients, will be identified and measured via an electronic search of the medical records nine months after the start of the intervention. Practitioners in the control group will receive a printed copy of the guideline. In

Extended Traffic Crash Modelling through Precision and Response Time Using Fuzzy Clustering Algorithms Compared with Multi-layer Perceptron

Directory of Open Access Journals (Sweden)

Iman Aghayan

2012-11-01

Full Text Available This paper compares two fuzzy clustering algorithms – fuzzy subtractive clustering and fuzzy C-means clustering – to a multi-layer perceptron neural network for their ability to predict the severity of crash injuries and to estimate the response time on the traffic crash data. Four clustering algorithms – hierarchical, K-means, subtractive clustering, and fuzzy C-means clustering – were used to obtain the optimum number of clusters based on the mean silhouette coefficient and R-value before applying the fuzzy clustering algorithms. The best-fit algorithms were selected according to two criteria: precision (root mean square, R-value, mean absolute errors, and sum of square error and response time (t. The highest R-value was obtained for the multi-layer perceptron (0.89, demonstrating that the multi-layer perceptron had a high precision in traffic crash prediction among the prediction models, and that it was stable even in the presence of outliers and overlapping data. Meanwhile, in comparison with other prediction models, fuzzy subtractive clustering provided the lowest value for response time (0.284 second, 9.28 times faster than the time of multi-layer perceptron, meaning that it could lead to developing an on-line system for processing data from detectors and/or a real-time traffic database. The model can be extended through improvements based on additional data through induction procedure.

Characterizing Heterogeneity within Head and Neck Lesions Using Cluster Analysis of Multi-Parametric MRI Data.

Directory of Open Access Journals (Sweden)

Marco Borri

Full Text Available To describe a methodology, based on cluster analysis, to partition multi-parametric functional imaging data into groups (or clusters of similar functional characteristics, with the aim of characterizing functional heterogeneity within head and neck tumour volumes. To evaluate the performance of the proposed approach on a set of longitudinal MRI data, analysing the evolution of the obtained sub-sets with treatment.The cluster analysis workflow was applied to a combination of dynamic contrast-enhanced and diffusion-weighted imaging MRI data from a cohort of squamous cell carcinoma of the head and neck patients. Cumulative distributions of voxels, containing pre and post-treatment data and including both primary tumours and lymph nodes, were partitioned into k clusters (k = 2, 3 or 4. Principal component analysis and cluster validation were employed to investigate data composition and to independently determine the optimal number of clusters. The evolution of the resulting sub-regions with induction chemotherapy treatment was assessed relative to the number of clusters.The clustering algorithm was able to separate clusters which significantly reduced in voxel number following induction chemotherapy from clusters with a non-significant reduction. Partitioning with the optimal number of clusters (k = 4, determined with cluster validation, produced the best separation between reducing and non-reducing clusters.The proposed methodology was able to identify tumour sub-regions with distinct functional properties, independently separating clusters which were affected differently by treatment. This work demonstrates that unsupervised cluster analysis, with no prior knowledge of the data, can be employed to provide a multi-parametric characterization of functional heterogeneity within tumour volumes.

Promoting smoking cessation in Pakistani and Bangladeshi men in the UK: pilot cluster randomised controlled trial of trained community outreach workers

Directory of Open Access Journals (Sweden)

Barton Pelham

2011-08-01

Full Text Available Abstract Background Smoking prevalence is high among Pakistani and Bangladeshi men in the UK, but there are few tailored smoking cessation programmes for Pakistani and Bangladeshi communities. The aim of this study was to pilot a cluster randomised controlled trial comparing the effectiveness of Pakistani and Bangladeshi smoking cessation outreach workers with standard care to improve access to and the success of English smoking cessation services. Methods A pilot cluster randomised controlled trial was conducted in Birmingham, UK. Geographical lower layer super output areas were used to identify natural communities where more than 10% of the population were of Pakistani and Bangladeshi origin. 16 agglomerations of super output areas were randomised to normal care controls vs. outreach intervention. The number of people setting quit dates using NHS services, validated abstinence from smoking at four weeks, and stated abstinence at three and six months were assessed. The impact of the intervention on choice and adherence to treatments, attendance at clinic appointments and patient satisfaction were also assessed. Results We were able to randomise geographical areas and deliver the outreach worker-based services. More Pakistani and Bangladeshi men made quit attempts with NHS services in intervention areas compared with control areas, rate ratio (RR 1.32 (95%CI: 1.03-1.69. There was a small increase in the number of 4-week abstinent smokers in intervention areas (RR 1.30, 95%CI: 0.82-2.06. The proportion of service users attending weekly appointments was lower in intervention areas than control areas. No difference was found between intervention and control areas in choice and adherence to treatments or patient satisfaction with the service. The total cost of the intervention was £124,000; an estimated cost per quality-adjusted life year (QALY gained of £8,500. Conclusions The intervention proved feasible and acceptable. Outreach workers expanded

Prediction of difficult mask ventilation using a systematic assessment of risk factors vs. existing practice - a cluster randomised clinical trial in 94,006 patients

DEFF Research Database (Denmark)

Nørskov, A K; Wetterslev, J; Rosenstock, C V

2017-01-01

We compared implementation of systematic airway assessment with existing practice of airway assessment on prediction of difficult mask ventilation. Twenty-six departments were cluster-randomised to assess eleven risk factors for difficult airway management (intervention) or to continue with their......We compared implementation of systematic airway assessment with existing practice of airway assessment on prediction of difficult mask ventilation. Twenty-six departments were cluster-randomised to assess eleven risk factors for difficult airway management (intervention) or to continue...... with their existing airway assessment (control). In both groups, patients predicted as a difficult mask ventilation and/or difficult intubation were registered in the Danish Anaesthesia Database, with a notational summary of airway management. The trial's primary outcome was the respective incidence of unpredicted...... difficult and easy mask ventilation in the two groups. Among 94,006 patients undergoing mask ventilation, the incidence of unpredicted difficult mask ventilation in the intervention group was 0.91% and 0.88% in the control group; (OR) 0.98 (95% CI 0.66-1.44), p = 0.90. The incidence of patients predicted...

Predictors of primary care referrals to a vascular disease prevention lifestyle program among participants in a cluster randomised trial.

Science.gov (United States)

Passey, Megan E; Laws, Rachel A; Jayasinghe, Upali W; Fanaian, Mahnaz; McKenzie, Suzanne; Powell-Davies, Gawaine; Lyle, David; Harris, Mark F

2012-08-03

Cardiovascular disease accounts for a large burden of disease, but is amenable to prevention through lifestyle modification. This paper examines patient and practice predictors of referral to a lifestyle modification program (LMP) offered as part of a cluster randomised controlled trial (RCT) of prevention of vascular disease in primary care. Data from the intervention arm of a cluster RCT which recruited 36 practices through two rural and three urban primary care organisations were used. In each practice, 160 eligible high risk patients were invited to participate. Practices were randomly allocated to intervention or control groups. Intervention practice staff were trained in screening, motivational interviewing and counselling and encouraged to refer high risk patients to a LMP involving individual and group sessions. Data include patient surveys; clinical audit; practice survey on capacity for preventive care; referral records from the LMP. Predictors of referral were examined using multi-level logistic regression modelling after adjustment for confounding factors. Of 301 eligible patients, 190 (63.1%) were referred to the LMP. Independent predictors of referral were baseline BMI ≥ 25 (OR 2.87 95%CI:1.10, 7.47), physical inactivity (OR 2.90 95%CI:1.36,6.14), contemplation/preparation/action stage of change for physical activity (OR 2.75 95%CI:1.07, 7.03), rural location (OR 12.50 95%CI:1.43, 109.7) and smaller practice size (1-3 GPs) (OR 16.05 95%CI:2.74, 94.24). Providing a well-structured evidence-based lifestyle intervention, free of charge to patients, with coordination and support for referral processes resulted in over 60% of participating high risk patients being referred for disease prevention. Contrary to expectations, referrals were more frequent from rural and smaller practices suggesting that these practices may be more ready to engage with these programs. ACTRN12607000423415.

Hemicraniectomy after middle cerebral artery infarction with life-threatening Edema trial (HAMLET). Protocol for a randomised controlled trial of decompressive surgery in space-occupying hemispheric infarction.

Science.gov (United States)

Hofmeijer, Jeannette; Amelink, G Johan; Algra, Ale; van Gijn, Jan; Macleod, Malcolm R; Kappelle, L Jaap; van der Worp, H Bart

2006-09-11

Patients with a hemispheric infarct and massive space-occupying brain oedema have a poor prognosis. Despite maximal conservative treatment, the case fatality rate may be as high as 80%, and most survivors are left severely disabled. Non-randomised studies suggest that decompressive surgery reduces mortality substantially and improves functional outcome of survivors. This study is designed to compare the efficacy of decompressive surgery to improve functional outcome with that of conservative treatment in patients with space-occupying supratentorial infarction The study design is that of a multi-centre, randomised clinical trial, which will include 112 patients aged between 18 and 60 years with a large hemispheric infarct with space-occupying oedema that leads to a decrease in consciousness. Patients will be randomised to receive either decompressive surgery in combination with medical treatment or best medical treatment alone. Randomisation will be stratified for the intended mode of conservative treatment (intensive care or stroke unit care). The primary outcome measure will be functional outcome, as determined by the score on the modified Rankin Scale, at one year.

Clustering of Multi-Temporal Fully Polarimetric L-Band SAR Data for Agricultural Land Cover Mapping

Science.gov (United States)

Tamiminia, H.; Homayouni, S.; Safari, A.

2015-12-01

Recently, the unique capabilities of Polarimetric Synthetic Aperture Radar (PolSAR) sensors make them an important and efficient tool for natural resources and environmental applications, such as land cover and crop classification. The aim of this paper is to classify multi-temporal full polarimetric SAR data using kernel-based fuzzy C-means clustering method, over an agricultural region. This method starts with transforming input data into the higher dimensional space using kernel functions and then clustering them in the feature space. Feature space, due to its inherent properties, has the ability to take in account the nonlinear and complex nature of polarimetric data. Several SAR polarimetric features extracted using target decomposition algorithms. Features from Cloude-Pottier, Freeman-Durden and Yamaguchi algorithms used as inputs for the clustering. This method was applied to multi-temporal UAVSAR L-band images acquired over an agricultural area near Winnipeg, Canada, during June and July in 2012. The results demonstrate the efficiency of this approach with respect to the classical methods. In addition, using multi-temporal data in the clustering process helped to investigate the phenological cycle of plants and significantly improved the performance of agricultural land cover mapping.

Six-monthly vitamin A from 1 to 6 years of age DEVTA: cluster ...

Indian Academy of Sciences (India)

Six-monthly vitamin A from 1 to 6 years of age DEVTA: cluster-randomised trial in 1 million children in Northern India · Pre-school rural Northern India · DEVTA: cluster-randomised trial in 8000+ villages (ie, AWCs) in 72 clusters (ie, blocks) · DEVTA vitamin A schedule, 05/1999 - 04/2004 · DEVTA: biomedical monitoring.

The Effect of Brief Interventions on the Drinking Behaviour of Pregnant Women in a High-Risk Rural South African Community: A Cluster Randomised Trial

Science.gov (United States)

Marais, Sandra; Jordaan, Esme; Viljoen, Dennis; Olivier, Leana; de Waal, Johanna; Poole, Caroline

2011-01-01

The purpose of this paper is to assess the impact of a series of brief interventions (BIs) on anti-natal alcohol consumption of women from a disadvantaged and high-risk background attending state health clinics in a rural district, Western Cape Province, South Africa. A pragmatic cluster randomised trial design was followed. All pregnant women,…

A designated centre for people with disabilities operated by Brothers of Charity Services Galway, Galway

LENUS (Irish Health Repository)

Murphy, Andrew W

2005-07-29

BACKGROUND: The aim of the SPHERE study is to design, implement and evaluate tailored practice and personal care plans to improve the process of care and objective clinical outcomes for patients with established coronary heart disease (CHD) in general practice across two different health systems on the island of Ireland. CHD is a common cause of death and a significant cause of morbidity in Ireland. Secondary prevention has been recommended as a key strategy for reducing levels of CHD mortality and general practice has been highlighted as an ideal setting for secondary prevention initiatives. Current indications suggest that there is considerable room for improvement in the provision of secondary prevention for patients with established heart disease on the island of Ireland. The review literature recommends structured programmes with continued support and follow-up of patients; the provision of training, tailored to practice needs of access to evidence of effectiveness of secondary prevention; structured recall programmes that also take account of individual practice needs; and patient-centred consultations accompanied by attention to disease management guidelines. METHODS: SPHERE is a cluster randomised controlled trial, with practice-level randomisation to intervention and control groups, recruiting 960 patients from 48 practices in three study centres (Belfast, Dublin and Galway). Primary outcomes are blood pressure, total cholesterol, physical and mental health status (SF-12) and hospital re-admissions. The intervention takes place over two years and data is collected at baseline, one-year and two-year follow-up. Data is obtained from medical charts, consultations with practitioners, and patient postal questionnaires. The SPHERE intervention involves the implementation of a structured systematic programme of care for patients with CHD attending general practice. It is a multi-faceted intervention that has been developed to respond to barriers and solutions to

Family-centred care for hospitalised children aged 0-12 years.

Science.gov (United States)

Shields, Linda; Zhou, Huaqiong; Pratt, Jan; Taylor, Marjory; Hunter, Judith; Pascoe, Elaine

2012-10-17

This is an update of the Cochrane systematic review of family-centred care published in 2007 (Shields 2007). Family-centred care (FCC) is a widely used model in paediatrics, is thought to be the best way to provide care to children in hospital and is ubiquitous as a way of delivering care. When a child is admitted, the whole family is affected. In giving care, nurses, doctors and others must consider the impact of the child's admission on all family members. However, the effectiveness of family-centred care as a model of care has not been measured systematically. To assess the effects of family-centred models of care for hospitalised children aged from birth (unlike the previous version of the review, this update excludes premature neonates) to 12 years, when compared to standard models of care, on child, family and health service outcomes. In the original review, we searched up until 2004. For this update, we searched: the Cochrane Central Register of Controlled Trials (CENTRAL,The Cochrane Library, Issue 12 2011); MEDLINE (Ovid SP); EMBASE (Ovid SP); PsycINFO (Ovid SP); CINAHL (EBSCO Host); and Sociological Abstracts (CSA). We did not search three that were included in the original review: Social Work Abstracts, the Australian Medical Index and ERIC. We searched EMBASE in this update only and searched from 2004 onwards. There was no limitation by language. We performed literature searches in May and June 2009 and updated them again in December 2011. We searched for randomised controlled trials (RCTs) including cluster randomised trials in which family-centred care models are compared with standard models of care for hospitalised children (0 to 12 years, but excluding premature neonates). Studies had to meet criteria for family-centredness. In order to assess the degree of family-centredness, we used a modified rating scale based on a validated instrument, (same instrument used in the initial review), however, we decreased the family-centredness score for

Randomised and non-randomised studies to estimate the effect of community-level public health interventions: definitions and methodological considerations.

Science.gov (United States)

Schmidt, Wolf-Peter

2017-01-01

The preferred method to evaluate public health interventions delivered at the level of whole communities is the cluster randomised trial (CRT). The practical limitations of CRTs and the need for alternative methods continue to be debated. There is no consensus on how to classify study designs to evaluate interventions, and how different design features are related to the strength of evidence. This article proposes that most study designs for the evaluation of cluster-level interventions fall into four broad categories: the CRT, the non-randomised cluster trial (NCT), the controlled before-and-after study (CBA), and the before-and-after study without control (BA). A CRT needs to fulfil two basic criteria: (1) the intervention is allocated at random; (2) there are sufficient clusters to allow a statistical between-arm comparison. In a NCT, statistical comparison is made across trial arms as in a CRT, but treatment allocation is not random. The defining feature of a CBA is that intervention and control arms are not compared directly, usually because there are insufficient clusters in each arm to allow a statistical comparison. Rather, baseline and follow-up measures of the outcome of interest are compared in the intervention arm, and separately in the control arm. A BA is a CBA without a control group. Each design may provide useful or misleading evidence. A precise baseline measurement of the outcome of interest is critical for causal inference in all studies except CRTs. Apart from statistical considerations the exploration of pre/post trends in the outcome allows a more transparent discussion of study weaknesses than is possible in non-randomised studies without a baseline measure.

Social Dancing and Incidence of Falls in Older Adults: A Cluster Randomised Controlled Trial.

Science.gov (United States)

Merom, Dafna; Mathieu, Erin; Cerin, Ester; Morton, Rachael L; Simpson, Judy M; Rissel, Chris; Anstey, Kaarin J; Sherrington, Catherine; Lord, Stephen R; Cumming, Robert G

2016-08-01

The prevention of falls among older people is a major public health challenge. Exercises that challenge balance are recognized as an efficacious fall prevention strategy. Given that small-scale trials have indicated that diverse dance styles can improve balance and gait of older adults, two of the strongest risk factors for falls in older people, this study aimed to determine whether social dance is effective in i) reducing the number of falls and ii) improving physical and cognitive fall-related risk factors. A parallel two-arm cluster randomized controlled trial was undertaken in 23 self-care retirement villages (clusters) around Sydney, Australia. Eligible villages had to have an appropriate hall for dancing, house at least 60 residents, and not be currently offering dance as a village activity. Retirement villages were randomised using a computer generated randomisation method, constrained using minimisation. Eligible participants had to be a resident of the village, be able to walk at least 50 m, and agree to undergo physical and cognitive testing without cognitive impairment. Residents of intervention villages (12 clusters) were offered twice weekly one-hour social dancing classes (folk or ballroom dancing) over 12 mo (80 h in total). Programs were standardized across villages and were delivered by eight dance teachers. Participants in the control villages (11 clusters) were advised to continue with their regular activities. falls during the 12 mo trial and Trail Making Tests. The Physiological Performance Assessment (i.e., postural sway, proprioception, reaction time, leg strength) and the Short Physical Performance Battery; health-related physical and mental quality of life from the Short-Form 12 (SF-12) Survey. Data on falls were obtained from 522 of 530 (98%) randomised participants (mean age 78 y, 85% women) and 424 (80%) attended the 12-mo reassessment, which was lower among folk dance participants (71%) than ballroom dancing (82%) or control

Social Dancing and Incidence of Falls in Older Adults: A Cluster Randomised Controlled Trial.

Directory of Open Access Journals (Sweden)

Dafna Merom

2016-08-01

Full Text Available The prevention of falls among older people is a major public health challenge. Exercises that challenge balance are recognized as an efficacious fall prevention strategy. Given that small-scale trials have indicated that diverse dance styles can improve balance and gait of older adults, two of the strongest risk factors for falls in older people, this study aimed to determine whether social dance is effective in i reducing the number of falls and ii improving physical and cognitive fall-related risk factors.A parallel two-arm cluster randomized controlled trial was undertaken in 23 self-care retirement villages (clusters around Sydney, Australia. Eligible villages had to have an appropriate hall for dancing, house at least 60 residents, and not be currently offering dance as a village activity. Retirement villages were randomised using a computer generated randomisation method, constrained using minimisation. Eligible participants had to be a resident of the village, be able to walk at least 50 m, and agree to undergo physical and cognitive testing without cognitive impairment. Residents of intervention villages (12 clusters were offered twice weekly one-hour social dancing classes (folk or ballroom dancing over 12 mo (80 h in total. Programs were standardized across villages and were delivered by eight dance teachers. Participants in the control villages (11 clusters were advised to continue with their regular activities.falls during the 12 mo trial and Trail Making Tests.The Physiological Performance Assessment (i.e., postural sway, proprioception, reaction time, leg strength and the Short Physical Performance Battery; health-related physical and mental quality of life from the Short-Form 12 (SF-12 Survey. Data on falls were obtained from 522 of 530 (98% randomised participants (mean age 78 y, 85% women and 424 (80% attended the 12-mo reassessment, which was lower among folk dance participants (71% than ballroom dancing (82% or control

Cost-effectiveness of the Australian Medical Sheepskin for the prevention of pressure ulcers in somatic nursing home patients: study protocol for a prospective multi-centre randomised controlled trial (ISRCTN17553857

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Montgomery Ken

2008-01-01

Full Text Available Abstract Background Pressure ulcers are a major problem, especially in nursing home patients, although they are regarded as preventable and there are many pressure relieving methods and materials. One such pressure relieving material is the recently developed Australian Medical Sheepskin, which has been shown in two randomized controlled trials 12 to be an effective intervention in the prevention of sacral pressure ulcers in hospital patients. However, the use of sheepskins has been debated and in general discouraged by most pressure ulcer working groups and pressure ulcer guidelines, but these debates were based on old forms of sheepskins. Furthermore, nothing is yet known about the (cost-effectiveness of the Australian Medical sheepskin in nursing home patients. The objective of this study is to assess the effects and costs of the use of the Australian Medical Sheepskin combined with usual care with regard to the prevention of sacral pressure ulcers in somatic nursing home patients, versus usual care only. Methods/Design In a multi-centre randomised controlled trial 750 patients admitted for a primarily somatic reason to one of the five participating nursing homes, and not having pressure ulcers on the sacrum at admission, will be randomized to either usual care only or usual care plus the use of the Australian Medical Sheepskin as an overlay on the mattress. Outcome measures are: incidence of sacral pressure ulcers in the first month after admission; sacrum pressure ulcer free days; costs; patient comfort; and ease of use. The skin of all the patients will be observed once a day from admission on for 30 days. Patient characteristics and pressure risk scores are assessed at admission and at day 30 after it. Additional to the empirical phase, systematic reviews will be performed in order to obtain data for economic weighting and modelling. The protocol is registered in the Controlled Trial Register as ISRCTN17553857.

Schedulability Analysis and Optimization for the Synthesis of Multi-Cluster Distributed Embedded Systems

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2003-01-01

We present an approach to schedulability analysis for the synthesis of multi-cluster distributed embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways. We have also proposed a buffer size and worst case queuing delay analysis for the gateways......, responsible for routing inter-cluster traffic. Optimization heuristics for the priority assignment and synthesis of bus access parameters aimed at producing a schedulable system with minimal buffer needs have been proposed. Extensive experiments and a real-life example show the efficiency of our approaches....

Schedulability Analysis and Optimization for the Synthesis of Multi-Cluster Distributed Embedded Systems

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2003-01-01

An approach to schedulability analysis for the synthesis of multi-cluster distributed embedded systems consisting of time-triggered and event-triggered clusters, interconnected via gateways, is presented. A buffer size and worst case queuing delay analysis for the gateways, responsible for routing...... inter-cluster traffic, is also proposed. Optimisation heuristics for the priority assignment and synthesis of bus access parameters aimed at producing a schedulable system with minimal buffer needs have been proposed. Extensive experiments and a real-life example show the efficiency of the approaches....

Multi-Cluster Network on a Chip Reconfigurable Radiation Hardened Radio, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The objective of the Phase-I research is to architect, model and simulate a multi-cluster Network on a Chip (NoC) reconfigurable Radio in SystemC RTL, with...

Psycho-education with problem solving (PEPS therapy for adults with personality disorder: A pragmatic multi-site community-based randomised clinical trial

Directory of Open Access Journals (Sweden)

Duggan Conor

2011-08-01

Full Text Available Abstract Background Impairment in social functioning is a key component of personality disorder. Therefore psycho-education and problem solving (PEPS therapy may benefit people with this disorder. Psycho-education aims to educate, build rapport, and motivate people for problem solving therapy. Problem solving therapy aims to help clients solve interpersonal problems positively and rationally, thereby improving social functioning and reducing distress. PEPS therapy has been evaluated with community adults with personality disorder in an exploratory trial. At the end of treatment, compared to a wait-list control group, those treated with PEPS therapy showed better social functioning, as measured by the Social Functioning Questionnaire (SFQ. A definitive evaluation is now being conducted to determine whether PEPS therapy is a clinically and cost-effective treatment for people with personality disorder Methods This is a pragmatic, two-arm, multi-centre, parallel, randomised controlled clinical trial. The target population is community-dwelling adults with one or more personality disorder, as identified by the International Personality Disorder Examination (IPDE. Inclusion criteria are: Living in the community (including residential or supported care settings; presence of one or more personality disorder; aged 18 or over; proficiency in spoken English; capacity to provide informed consent. Exclusion criteria are: Primary diagnosis of a functional psychosis; insufficient degree of literacy, comprehension or attention to be able to engage in trial therapy and assessments; currently engaged in a specific programme of psychological treatment for personality disorder or likely to start such treatment during the trial period; currently enrolled in any other trial. Suitable participants are randomly allocated to PEPS therapy plus treatment as usual (TAU or TAU only. We aim to recruit 340 men and women. The primary outcome is social functioning as measured

A-centres build-up kinetics in the conductive matrix of pulled n-type silicon with calculation of their recharges at defect clusters

International Nuclear Information System (INIS)

Dolgolenko, A.P.; Fishchuk, I.I.

1981-01-01

Pulled n-Si samples with rho approximately 40 Ωcm are investigated after irradiation with different doses of fast-pile neutrons. It is known that the simple defects are created not only in the conductive matrix but also in the region of the space charge of defect clusters. Then the charge state, for example, of A-centres in the region of the space charge is defined by both, the temperature and the value of the electrostatical potential. If this circumstance is not taken into account the calculation of the conductive volume is not precise enough. In the present paper the temperature dependence of the volume fraction is calculated, in which the space charge of defect clusters occurs, taking into account the recharges of A-centres in the region of the space charge. Using the expression obtained the A-centres build-up kinetics in the conductive matrix of pulled n-type silicon is calculated. (author)

A priori data-driven multi-clustered reservoir generation algorithm for echo state network.

Directory of Open Access Journals (Sweden)

Xiumin Li

Full Text Available Echo state networks (ESNs with multi-clustered reservoir topology perform better in reservoir computing and robustness than those with random reservoir topology. However, these ESNs have a complex reservoir topology, which leads to difficulties in reservoir generation. This study focuses on the reservoir generation problem when ESN is used in environments with sufficient priori data available. Accordingly, a priori data-driven multi-cluster reservoir generation algorithm is proposed. The priori data in the proposed algorithm are used to evaluate reservoirs by calculating the precision and standard deviation of ESNs. The reservoirs are produced using the clustering method; only the reservoir with a better evaluation performance takes the place of a previous one. The final reservoir is obtained when its evaluation score reaches the preset requirement. The prediction experiment results obtained using the Mackey-Glass chaotic time series show that the proposed reservoir generation algorithm provides ESNs with extra prediction precision and increases the structure complexity of the network. Further experiments also reveal the appropriate values of the number of clusters and time window size to obtain optimal performance. The information entropy of the reservoir reaches the maximum when ESN gains the greatest precision.

A cluster randomised controlled trial of a nutrition education intervention in the community.

Science.gov (United States)

Madigan, S M; Fleming, P; Wright, M E; Stevenson, M; Macauley, D

2014-04-01

Patients with enteral feeding tubes are increasingly managed in their home environment and these patients require support from a range of healthcare professionals. A cluster randomised trial of an educational intervention was undertaken among General Practitioners and nurses both in the community and in nursing home caring for patients recently discharged to primary care. This was a short, duration (nutrition education programme delivered in the work place soon after the patient was discharged from hospital. The primary outcome was an improvement in knowledge immediately after the intervention and the secondary outcome was knowledge at 6 months. Those in the intervention group had improved knowledge, which was significantly greater than those in the control group (P work-based targeted nutrition education programme is effective for improving knowledge among general practitioners and nurses both in the community and in nursing homes. © 2013 The Authors Journal of Human Nutrition and Dietetics © 2013 The British Dietetic Association Ltd.

A community mobilisation intervention to prevent violence against women and reduce HIV/AIDS risk in Kampala, Uganda (the SASA! Study): study protocol for a cluster randomised controlled trial.

Science.gov (United States)

Abramsky, Tanya; Devries, Karen; Kiss, Ligia; Francisco, Leilani; Nakuti, Janet; Musuya, Tina; Kyegombe, Nambusi; Starmann, Elizabeth; Kaye, Dan; Michau, Lori; Watts, Charlotte

2012-06-29

Gender based violence, including violence by an intimate partner, is a major global human rights and public health problem, with important connections with HIV risk. Indeed, the elimination of sexual and gender based violence is a core pillar of HIV prevention for UNAIDS. Integrated strategies to address the gender norms, relations and inequities that underlie both violence against women and HIV/AIDS are needed. However there is limited evidence about the potential impact of different intervention models. This protocol describes the SASA! an evaluation of a community mobilisation intervention to prevent violence against women and reduce HIV/AIDS risk in Kampala, Uganda. The SASA! STUDY is a pair-matched cluster randomised controlled trial being conducted in eight communities in Kampala. It is designed to assess the community-level impact of the SASA! intervention on the following six primary outcomes: attitudes towards the acceptability of violence against women and the acceptability of a woman refusing sex (among male and female community members); past year experience of physical intimate partner violence and sexual intimate partner violence (among females); community responses to women experiencing violence (among women reporting past year physical/sexual partner violence); and past year concurrency of sexual partners (among males). 1583 women and men (aged 18-49 years) were surveyed in intervention and control communities prior to intervention implementation in 2007/8. A follow-up cross-sectional survey of community members will take place in 2012. The primary analysis will be an adjusted cluster-level intention to treat analysis, comparing outcomes in intervention and control communities at follow-up. Complementary monitoring and evaluation and qualitative research will be used to explore and describe the process of intervention implementation and the pathways through which change is achieved. This is one of few cluster randomised trials globally to assess

A community mobilisation intervention to prevent violence against women and reduce HIV/AIDS risk in Kampala, Uganda (the SASA! Study): study protocol for a cluster randomised controlled trial

Science.gov (United States)

2012-01-01

cluster randomised trials globally to assess the impact of a gender-focused community mobilisation intervention. The multi-disciplinary research approach will enable us to address questions of intervention impact and mechanisms of action, as well as its feasibility, acceptability and transferability to other contexts. The results will be of importance to researchers, policy makers and those working on the front line to prevent violence against women and HIV. Trial registration ClinicalTrials.Gov NCT00790959 PMID:22747846

Centre-excised X-ray luminosity as an efficient mass proxy for future galaxy cluster surveys

Science.gov (United States)

Mantz, Adam B.; Allen, Steven W.; Morris, R. Glenn; von der Linden, Anja

2018-01-01

The cosmological constraining power of modern galaxy cluster catalogues can be improved by obtaining low-scatter mass proxy measurements for even a small fraction of sources. In the context of large upcoming surveys that will reveal the cluster population down to the group scale and out to high redshifts, efficient strategies for obtaining such mass proxies will be valuable. In this work, we use high-quality weak-lensing and X-ray mass estimates for massive clusters in current X-ray-selected catalogues to revisit the scaling relations of the projected, centre-excised X-ray luminosity (Lce), which previous work suggests correlates tightly with total mass. Our data confirm that this is the case with Lce having an intrinsic scatter at fixed mass comparable to that of gas mass, temperature or YX. Compared to the other proxies, however, Lce is less susceptible to systematic uncertainties due to background modelling, and can be measured precisely with shorter exposures. This opens up the possibility of using Lce to estimate masses for large numbers of clusters discovered by new X-ray surveys (e.g. eROSITA) directly from the survey data, as well as for clusters discovered at other wavelengths with relatively short follow-up observations. We describe a simple procedure for making such estimates from X-ray surface brightness data, and comment on the spatial resolution required to apply this method as a function of cluster mass and redshift. We also explore the potential impact of Chandra and XMM-Newton follow-up observations over the next decade on dark energy constraints from new cluster surveys.

An Ontological-Fuzzy Approach to Advance Reservation in Multi-Cluster Grids

International Nuclear Information System (INIS)

Ferreira, D J; Dantas, M A R; Bauer, Michael A

2010-01-01

Advance reservation is an important mechanism for a successful utilization of available resources in distributed multi-cluster environments. This mechanism allows, for example, a user to provide parameters aiming to satisfy requirements related to applications' execution time and temporal dependence. This predictability can lead the system to reach higher levels of QoS. However, the support for advance reservation has been restricted due to the complexity of large scale configurations and also dynamic changes verified in these systems. In this research work it is proposed an advance reservation method, based on a ontology-fuzzy approach. It allows a user to reserve a wide variety of resources and enable large jobs to be reserved among different nodes. In addition, it dynamically verifies the possibility of reservation with the local RMS, avoiding future allocation conflicts. Experimental results of the proposal, through simulation, indicate that the proposed mechanism reached a successful level of flexibility for large jobs and more appropriated distribution of resources in a distributed multi-cluster configuration.

Matrix multiplication with a hypercube algorithm on multi-core processor cluster

Directory of Open Access Journals (Sweden)

José Crispín Zavala-Díaz

2015-01-01

Full Text Available Se analiza, modifica e implementa el algoritmo de multiplicación de matrices de Dekel, Nassimi y Sahani o hipercubo en un cluster de procesadores multi-core, donde el número de procesadores utilizado es menor al requerido por el algoritmo de n3. Se utilizan 23, 43 y 83 unidades procesadoras para multiplicar matrices de orden de magnitud de 10X10, 102X102 y 103X103. Los resultados del modelo matemático del algoritmo modificado y los obtenidos de la experimentación computacional muestran que es posible alcanzar rapidez y eficiencias paralelas aceptables, en función del número de unidades procesadoras utilizadas. También se muestra que la influencia del enlace externo de comunicación entre los nodos disminuye si se utiliza una combinación de los canales de comunicación disponibles entre los núcleos en un cluster multi-core.

An Ontological-Fuzzy Approach to Advance Reservation in Multi-Cluster Grids

Energy Technology Data Exchange (ETDEWEB)

Ferreira, D J; Dantas, M A R; Bauer, Michael A, E-mail: ded@inf.ufsc.br, E-mail: mario@inf.ufsc.br, E-mail: bauer@csd.uwo.ca

2010-11-01

Advance reservation is an important mechanism for a successful utilization of available resources in distributed multi-cluster environments. This mechanism allows, for example, a user to provide parameters aiming to satisfy requirements related to applications' execution time and temporal dependence. This predictability can lead the system to reach higher levels of QoS. However, the support for advance reservation has been restricted due to the complexity of large scale configurations and also dynamic changes verified in these systems. In this research work it is proposed an advance reservation method, based on a ontology-fuzzy approach. It allows a user to reserve a wide variety of resources and enable large jobs to be reserved among different nodes. In addition, it dynamically verifies the possibility of reservation with the local RMS, avoiding future allocation conflicts. Experimental results of the proposal, through simulation, indicate that the proposed mechanism reached a successful level of flexibility for large jobs and more appropriated distribution of resources in a distributed multi-cluster configuration.

The impact of study design and diagnostic approach in a large multi-centre ADHD study. Part 1: ADHD symptom patterns

Directory of Open Access Journals (Sweden)

Roeyers Herbert

2011-04-01

Full Text Available Abstract Background The International Multi-centre ADHD Genetics (IMAGE project with 11 participating centres from 7 European countries and Israel has collected a large behavioural and genetic database for present and future research. Behavioural data were collected from 1068 probands with the combined type of attention deficit/hyperactivity disorder (ADHD-CT and 1446 'unselected' siblings. The aim was to analyse the IMAGE sample with respect to demographic features (gender, age, family status, and recruiting centres and psychopathological characteristics (diagnostic subtype, symptom frequencies, age at symptom detection, and comorbidities. A particular focus was on the effects of the study design and the diagnostic procedure on the homogeneity of the sample in terms of symptom-based behavioural data, and potential consequences for further analyses based on these data. Methods Diagnosis was based on the Parental Account of Childhood Symptoms (PACS interview and the DSM-IV items of the Conners' teacher questionnaire. Demographics of the full sample and the homogeneity of a subsample (all probands were analysed by using robust statistical procedures which were adjusted for unequal sample sizes and skewed distributions. These procedures included multi-way analyses based on trimmed means and winsorised variances as well as bootstrapping. Results Age and proband/sibling ratios differed between participating centres. There was no significant difference in the distribution of gender between centres. There was a significant interaction between age and centre for number of inattentive, but not number of hyperactive symptoms. Higher ADHD symptom frequencies were reported by parents than teachers. The diagnostic symptoms differed from each other in their frequencies. The face-to-face interview was more sensitive than the questionnaire. The differentiation between ADHD-CT probands and unaffected siblings was mainly due to differences in hyperactive

The impact of study design and diagnostic approach in a large multi-centre ADHD study. Part 1: ADHD symptom patterns.

LENUS (Irish Health Repository)

Muller, Ueli C

2011-04-07

Abstract Background The International Multi-centre ADHD Genetics (IMAGE) project with 11 participating centres from 7 European countries and Israel has collected a large behavioural and genetic database for present and future research. Behavioural data were collected from 1068 probands with the combined type of attention deficit\\/hyperactivity disorder (ADHD-CT) and 1446 \\'unselected\\' siblings. The aim was to analyse the IMAGE sample with respect to demographic features (gender, age, family status, and recruiting centres) and psychopathological characteristics (diagnostic subtype, symptom frequencies, age at symptom detection, and comorbidities). A particular focus was on the effects of the study design and the diagnostic procedure on the homogeneity of the sample in terms of symptom-based behavioural data, and potential consequences for further analyses based on these data. Methods Diagnosis was based on the Parental Account of Childhood Symptoms (PACS) interview and the DSM-IV items of the Conners\\' teacher questionnaire. Demographics of the full sample and the homogeneity of a subsample (all probands) were analysed by using robust statistical procedures which were adjusted for unequal sample sizes and skewed distributions. These procedures included multi-way analyses based on trimmed means and winsorised variances as well as bootstrapping. Results Age and proband\\/sibling ratios differed between participating centres. There was no significant difference in the distribution of gender between centres. There was a significant interaction between age and centre for number of inattentive, but not number of hyperactive symptoms. Higher ADHD symptom frequencies were reported by parents than teachers. The diagnostic symptoms differed from each other in their frequencies. The face-to-face interview was more sensitive than the questionnaire. The differentiation between ADHD-CT probands and unaffected siblings was mainly due to differences in hyperactive

The impact of a disease management program (COACH on the attainment of better cardiovascular risk control in dyslipidaemic patients at primary care centres (The DISSEMINATE Study: a randomised controlled trial

Directory of Open Access Journals (Sweden)

Selvaraj Francis Jude

2012-10-01

Full Text Available Abstract Background To evaluate the efficacy of Counselling and Advisory Care for Health (COACH programme in managing dyslipidaemia among primary care practices in Malaysia. This open-label, parallel, randomised controlled trial compared the COACH programme delivered by primary care physicians alone (PCP arm and primary care physicians assisted by nurse educators (PCP-NE arm. Methods This was a multi-centre, open label, randomised trial of a disease management programme (COACH among dyslipidaemic patients in 21 Malaysia primary care practices. The participating centres enrolled 297 treatment naïve subjects who had the primary diagnosis of dyslipidaemia; 149 were randomised to the COACH programme delivered by primary care physicians assisted by nurse educators (PCP-NE and 148 to care provided by primary care physicians (PCP alone. The primary efficacy endpoint was the mean percentage change from baseline LDL-C at week 24 between the 2 study arms. Secondary endpoints included mean percentage change from baseline of lipid profile (TC, LDL-C, HDL-C, TG, TC: HDL ratio, Framingham Cardiovascular Health Risk Score and absolute risk change from baseline in blood pressure parameters at week 24. The study also assessed the sustainability of programme efficacy at week 36. Results Both study arms demonstrated improvement in LDL-C from baseline. The least squares (LS mean change from baseline LDL-C were −30.09% and −27.54% for PCP-NE and PCP respectively. The difference in mean change between groups was 2.55% (p=0.288, with a greater change seen in the PCP-NE arm. Similar observations were made between the study groups in relation to total cholesterol change at week 24. Significant difference in percentage change from baseline of HDL-C were observed between the PCP-NE and PCP groups, 3.01%, 95% CI 0.12-5.90, p=0.041, at week 24. There was no significant difference in lipid outcomes between 2 study groups at week 36 (12 weeks after the programme had

Study protocol to assess the effectiveness and safety of a flexible family visitation model for delirium prevention in adult intensive care units: a cluster-randomised, crossover trial (The ICU Visits Study).

Science.gov (United States)

Rosa, Regis Goulart; Falavigna, Maicon; Robinson, Caroline Cabral; da Silva, Daiana Barbosa; Kochhann, Renata; de Moura, Rafaela Moraes; Santos, Mariana Martins Siqueira; Sganzerla, Daniel; Giordani, Natalia Elis; Eugênio, Cláudia; Ribeiro, Tarissa; Cavalcanti, Alexandre Biasi; Bozza, Fernando; Azevedo, Luciano Cesar Pontes; Machado, Flávia Ribeiro; Salluh, Jorge Ibrain Figueira; Pellegrini, José Augusto Santos; Moraes, Rafael Barberena; Hochegger, Taís; Amaral, Alexandre; Teles, José Mario Meira; da Luz, Lucas Gobetti; Barbosa, Mirceli Goulart; Birriel, Daniella Cunha; Ferraz, Iris de Lima; Nobre, Vandack; Valentim, Helen Martins; Corrêa E Castro, Livia; Duarte, Péricles Almeida Delfino; Tregnago, Rogério; Barilli, Sofia Louise Santin; Brandão, Nilton; Giannini, Alberto; Teixeira, Cassiano

2018-04-13

Flexible intensive care unit (ICU) visiting hours have been proposed as a means to improve patient-centred and family-centred care. However, randomised trials evaluating the effects of flexible family visitation models (FFVMs) are scarce. This study aims to compare the effectiveness and safety of an FFVM versus a restrictive family visitation model (RFVM) on delirium prevention among ICU patients, as well as to analyse its potential effects on family members and ICU professionals. A cluster-randomised crossover trial involving adult ICU patients, family members and ICU professionals will be conducted. Forty medical-surgical Brazilian ICUs with RFVMs (<4.5 hours/day) will be randomly assigned to either an RFVM (visits according to local policies) or an FFVM (visitation during 12 consecutive hours per day) group at a 1:1 ratio. After enrolment and follow-up of 25 patients, each ICU will be switched over to the other visitation model, until 25 more patients per site are enrolled and followed. The primary outcome will be the cumulative incidence of delirium among ICU patients, measured twice a day using the Confusion Assessment Method for the ICU. Secondary outcome measures will include daily hazard of delirium, ventilator-free days, any ICU-acquired infections, ICU length of stay and hospital mortality among the patients; symptoms of anxiety and depression and satisfaction among the family members; and prevalence of burnout symptoms among the ICU professionals. Tertiary outcomes will include need for antipsychotic agents and/or mechanical restraints, coma-free days, unplanned loss of invasive devices and ICU-acquired pneumonia, urinary tract infection or bloodstream infection among the patients; self-perception of involvement in patient care among the family members; and satisfaction among the ICU professionals. The study protocol has been approved by the research ethics committee of all participant institutions. We aim to disseminate the findings through

Multi-scale Clustering of Points Synthetically Considering Lines and Polygons Distribution

Directory of Open Access Journals (Sweden)

YU Li

2015-10-01

Full Text Available Considering the complexity and discontinuity of spatial data distribution, a clustering algorithm of points was proposed. To accurately identify and express the spatial correlation among points,lines and polygons, a Voronoi diagram that is generated by all spatial features is introduced. According to the distribution characteristics of point's position, an area threshold used to control clustering granularity was calculated. Meanwhile, judging scale convergence by constant area threshold, the algorithm classifies spatial features based on multi-scale, with an O(n log n running time.Results indicate that spatial scale converges self-adaptively according with distribution of points.Without the custom parameters, the algorithm capable to discover arbitrary shape clusters which be bound by lines and polygons, and is robust for outliers.

Multi-centre experience of implementing image-guided intensity-modulated radiotherapy using the TomoTherapy platform

International Nuclear Information System (INIS)

Dean, J.C.; Tudor, G.S.J.; Mott, J.H.; Dunlop, P.R.; Morris, S.L.; Harron, E.C.; Christian, J.A.; Sanghera, P.; Elsworthy, M.; Burnet, N.G.

2013-01-01

Use of image guided (IG) intensity modulated radiotherapy (IMRT) is increasing, and helical tomotherapy provides an effective, integrated solution. Practical experience of implementation, shared at a recent UK TomoTherapy Users' meeting, may help centres introducing these techniques using TomoTherapy or other platforms. Seven centres participated, with data shared from 6, varying from 2500 - 4800 new patients per year. Case selection of patients “most likely” to benefit from IG-IMRT was managed in all centres by multi-professional groups comprising clinical oncologists, physicists, treatment planners and radiographers. Radical treatments ranged from 94% to 100%. The proportions of tumour types varied substantially: head and neck: range 0%–100% (mean of centres 50%), prostate: 3%–96% (mean of centres 28%). Head and neck cases were considered most likely to benefit from IMRT, prostate cases from IGRT, or IG-IMRT if pelvic nodes were being treated. IMRT was also selected for complex target volumes, to avoid field junctions, for technical treatment difficulties, and retreatments. Across the centres, every patient was imaged every day, with positional correction before treatment. In one centre, for prostate patients including pelvic treatment, the pelvis was also imaged weekly. All centres had designed a ‘ramp up’ of patient numbers, which was similar in 5. One centre, treating 96% prostate patients, started with 3 and increased to 36 patients per day within 3 months. The variation in case mix implies wide applicability of IG-IMRT. Daily on-line IGRT with IMRT can be routinely implemented into busy departments

Evaluating the effect of innovative motivation and supervision approaches on community health worker performance and retention in Uganda and Mozambique: study protocol for a randomised controlled trial.

Science.gov (United States)

Källander, Karin; Strachan, Daniel; Soremekun, Seyi; Hill, Zelee; Lingam, Raghu; Tibenderana, James; Kasteng, Frida; Vassall, Anna; Meek, Sylvia; Kirkwood, Betty

2015-04-12

If trained, equipped and utilised, community health workers (CHWs) delivering integrated community case management for sick children can potentially reduce child deaths by 60%. However, it is essential to maintain CHW motivation and performance. The inSCALE project aims to evaluate, using a cluster randomised controlled trial, the effect of interventions to increase CHW supervision and performance on the coverage of appropriate treatment for children with diarrhoea, pneumonia and malaria. Participatory methods were used to identify best practices and innovative solutions. Quantitative community based baseline surveys were conducted to allow restricted randomisation of clusters into intervention and control arms. Individual informed consent was obtained from all respondents. Following formative research and stakeholder consultations, two intervention packages were developed in Uganda and one in Mozambique. In Uganda, approximately 3,500 CHWs in 39 clusters were randomised into a mobile health (mHealth) arm, a participatory community engagement arm and a control arm. In Mozambique, 275 CHWs in 12 clusters were randomised into a mHealth arm and a control arm. The mHealth interventions encompass three components: 1) free phone communication between users; 2) data submission using phones with automated feedback, messages to supervisors for targeted supervision, and online data access for district statisticians; and 3) motivational messages. The community engagement arm in Uganda established village health clubs seeking to 1) improve the status and standing of CHWs, 2) increase demand for health services and 3) communicate that CHWs' work is important. Process evaluation was conducted after 10 months and end-line surveys will establish impact after 12 months in Uganda and 18 months in Mozambique. Main outcomes include proportion of sick children appropriately treated, CHW performance and motivation, and cost effectiveness of interventions. Study strengths include a user-centred

Extracting Synthetic Multi-Cluster Platform Configurations from Grid'5000 for Driving Simulation Experiments

OpenAIRE

Suter , Frédéric; Casanova , Henri

2007-01-01

This report presents a collection of synthetic but realistic distributed computing platform configurations. These configurations are intended for simulation experiments in the study of parallel applications on multi-cluster platforms.

Early intervention for adolescents with Patellofemoral Pain Syndrome - a pragmatic cluster randomised controlled trial

Science.gov (United States)

2012-01-01

Background Self-reported knee pain is highly prevalent among adolescents. As much as 50% of the non-specific knee pain may be attributed to Patellofemoral Pain Syndrome (PFPS). In the short term, exercise therapy appears to have a better effect than patient education consisting of written information and general advice on exercise or compared with placebo treatment. But the long-term effect of exercise therapy compared with patient education is conflicting. The purpose of this study is to examine the short- and long-term effectiveness of patient education compared with patient education and multimodal physiotherapy applied at a very early stage of the condition among adolescents. Methods/Design This study is a single blind pragmatic cluster randomised controlled trial. Four upper secondary schools have been invited to participate in the study (approximately 2500 students, aged 15-19 years). Students are asked to answer an online questionnaire regarding musculoskeletal pain. The students who report knee pain are contacted by telephone and offered a clinical examination by a rheumatologist. Subjects who fit the inclusion criteria and are diagnosed with PFPS are invited to participate in the study. A minimum of 102 students with PFPS are then cluster-randomised into two intervention groups based on which school they attend. Both intervention groups receive written information and education. In addition to patient education, one group receives multimodal physiotherapy consisting primarily of neuromuscular training of the muscles around the foot, knee and hip and home exercises. The students with PFPS fill out self-reported questionnaires at baseline, 3, 6, 12 and 24 months after inclusion in the study. The primary outcome measure is perception of recovery measured on a 7-point Likert scale ranging from "completely recovered" to "worse than ever" at 12 months. Discussion This study is designed to investigate the effectiveness of patient education compared with patient

Home-based cardiac rehabilitation is as effective as centre-based cardiac rehabilitation among elderly with coronary heart disease: results from a randomised clinical trial

DEFF Research Database (Denmark)

Oerkild, Bodil; Frederiksen, Marianne; Hansen, Jorgen Fischer

2011-01-01

BACKGROUND: participation in centre-based cardiac rehabilitation (CR) is known to reduce morbidity and mortality but participation rates among the elderly are low. Establishing alternative programmes is important, and home-based CR is the predominant alternative. However, no studies have...... investigated the effect of home-based CR among a group of elderly patients with coronary heart disease with a long-term follow-up. METHODS: randomised clinical trial comparing home-based CR with comprehensive centre-based CR among patients = 65 years with coronary heart disease. RESULTS: seventy-five patients...... in the secondary outcomes of systolic blood pressure (-0.6 mmHg, 95% CI -11.3, 10.0), LDL cholesterol (0.3 mmol/l, 95% CI -0.04, 0.7), HDL cholesterol (0.2 mmol/l, 95% CI -0.01, 0.3), body composition, proportion of smokers and health-related quality of life. A group of patients who did not have an effect...

Person-centred web-based support--development through a Swedish multi-case study.

Science.gov (United States)

Josefsson, Ulrika; Berg, Marie; Koinberg, Ingalill; Hellström, Anna-Lena; Nolbris, Margaretha Jenholt; Ranerup, Agneta; Lundin, Carina Sparud; Skärsäter, Ingela

2013-10-19

Departing from the widespread use of the internet in modern society and the emerging use of web applications in healthcare this project captures persons' needs and expectations in order to develop highly usable web recourses. The purpose of this paper is to outline a multi-case research project focused on the development and evaluation of person-centred web-based support for people with long-term illness. To support the underlying idea to move beyond the illness, we approach the development of web support from the perspective of the emergent area of person-centred care. The project aims to contribute to the ongoing development of web-based supports in health care and to the emerging field of person-centred care. The research design uses a meta-analytical approach through its focus on synthesizing experiences from four Swedish regional and national cases of design and use of web-based support in long-term illness. The cases include children (bladder dysfunction and urogenital malformation), young adults (living close to persons with mental illness), and two different cases of adults (women with breast cancer and childbearing women with type 1 diabetes). All of the cases are ongoing, though in different stages of design, implementation, and analysis. This, we argue, will lead to a synthesis of results on a meta-level not yet described. To allow valid comparisons between the four cases we explore and problematize them in relation to four main aspects: 1) The use of people's experiences and needs; 2) The role of use of theories in the design of person-centred web-based supports; 3) The evaluation of the effects of health outcomes for the informants involved and 4) The development of a generic person-centred model for learning and social support for people with long-term illness and their significant others. Person-centred web-based support is a new area and few studies focus on how web-based interventions can contribute to the development of person-centred care. In

Mediating effects of resistance training skill competency on health-related fitness and physical activity: the ATLAS cluster randomised controlled trial.

Science.gov (United States)

Smith, Jordan J; Morgan, Philip J; Plotnikoff, Ronald C; Stodden, David F; Lubans, David R

2016-01-01

The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered "at-risk" of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys.

SMART: self-management of anticoagulation, a randomised trial [ISRCTN19313375].

Science.gov (United States)

McCahon, Deborah; Fitzmaurice, David A; Murray, Ellen T; Fuller, Christopher J; Hobbs, Richard F D; Allan, Teresa F; Raftery, James P

2003-09-18

Oral anticoagulation monitoring has traditionally taken place in secondary care because of the need for a laboratory blood test, the international normalised ratio (INR). The development of reliable near patient testing (NPT) systems for INR estimation has facilitated devolution of testing to primary care. Patient self-management is a logical progression from the primary care model. This study will be the first to randomise non-selected patients in primary care, to either self-management or standard care. The study was a multi-centred randomised controlled trial with patients from 49 general practices recruited. Those suitable for inclusion were aged 18 or over, with a long term indication for oral anticoagulation, who had taken warfarin for at least six months. Patients randomised to the intervention arm attended at least two training sessions which were practice-based, 1 week apart. Each patient was assessed on their capability to undertake self management. If considered capable, they were given a near patient INR testing monitor, test strips and quality control material for home testing. Patients managed their own anticoagulation for a period of 12 months and performed their INR test every 2 weeks. Control patients continued with their pre-study care either attending hospital or practice based anticoagulant clinics. The methodology used in this trial will overcome concerns from previous trials of selection bias and relevance to the UK health service. The study will give a clearer understanding of the benefits of self-management in terms of clinical and cost effectiveness and patient preference.

SMART: Self-Management of Anticoagulation, a Randomised Trial [ISRCTN19313375

Directory of Open Access Journals (Sweden)

Murray Ellen T

2003-09-01

Full Text Available Abstract Background Oral anticoagulation monitoring has traditionally taken place in secondary care because of the need for a laboratory blood test, the international normalised ratio (INR. The development of reliable near patient testing (NPT systems for INR estimation has facilitated devolution of testing to primary care. Patient self-management is a logical progression from the primary care model. This study will be the first to randomise non-selected patients in primary care, to either self-management or standard care. Method The study was a multi-centred randomised controlled trial with patients from 49 general practices recruited. Those suitable for inclusion were aged 18 or over, with a long term indication for oral anticoagulation, who had taken warfarin for at least six months. Patients randomised to the intervention arm attended at least two training sessions which were practice-based, 1 week apart. Each patient was assessed on their capability to undertake self management. If considered capable, they were given a near patient INR testing monitor, test strips and quality control material for home testing. Patients managed their own anticoagulation for a period of 12 months and performed their INR test every 2 weeks. Control patients continued with their pre-study care either attending hospital or practice based anticoagulant clinics. Discussion The methodology used in this trial will overcome concerns from previous trials of selection bias and relevance to the UK health service. The study will give a clearer understanding of the benefits of self-management in terms of clinical and cost effectiveness and patient preference.

Dynamical Friction in Multi-component Evolving Globular Clusters

Science.gov (United States)

Alessandrini, Emiliano; Lanzoni, Barbara; Miocchi, Paolo; Ciotti, Luca; Ferraro, Francesco R.

2014-11-01

We use the Chandrasekhar formalism and direct N-body simulations to study the effect of dynamical friction on a test object only slightly more massive than the field stars, orbiting a spherically symmetric background of particles with a mass spectrum. The main goal is to verify whether the dynamical friction time (t DF) develops a non-monotonic radial dependence that could explain the bimodality of the blue straggler radial distributions observed in globular clusters. In these systems, in fact, relaxation effects lead to a mass and velocity radial segregation of the different mass components, so that mass-spectrum effects on t DF are expected to be dependent on radius. We find that in spite of the presence of different masses, t DF is always a monotonic function of radius, at all evolutionary times and independently of the initial concentration of the simulated cluster. This is because the radial dependence of t DF is largely dominated by the total mass density profile of the background stars (which is monotonically decreasing with radius). Hence, a progressive temporal erosion of the blue straggler star (BSS) population at larger and larger distances from the cluster center remains the simplest and the most likely explanation of the shape of the observed BSS radial distributions, as suggested in previous works. We also confirm the theoretical expectation that approximating a multi-mass globular cluster as made of (averaged) equal-mass stars can lead to significant overestimations of t DF within the half-mass radius.

Effectiveness of a minimal intervention for stress-related mental disorders with sick leave (MISS): study protocol of a cluster randomised controlled trial in general practice [ISRCTN43779641

NARCIS (Netherlands)

Bakker, I.M.; Terluin, B.; van Marwijk, H.W.J.; Cundy, C.M.; Smit, J.H.; van Mechelen, W.; Stalman, W.A.B.

2006-01-01

Background: The main aims of this paper are to describe the setting and design of a Minimal Intervention in general practice for Stress-related mental disorders in patients on Sick leave (MISS), as well as to ascertain the study complies with the requirements for a cluster randomised controlled

The impact of study design and diagnostic approach in a large multi-centre ADHD study: Part 2: Dimensional measures of psychopathology and intelligence

Directory of Open Access Journals (Sweden)

Roeyers Herbert

2011-04-01

Full Text Available Abstract Background The International Multi-centre ADHD Genetics (IMAGE project with 11 participating centres from 7 European countries and Israel has collected a large behavioural and genetic database for present and future research. Behavioural data were collected from 1068 probands with ADHD and 1446 unselected siblings. The aim was to describe and analyse questionnaire data and IQ measures from all probands and siblings. In particular, to investigate the influence of age, gender, family status (proband vs. sibling, informant, and centres on sample homogeneity in psychopathological measures. Methods Conners' Questionnaires, Strengths and Difficulties Questionnaires, and Wechsler Intelligence Scores were used to describe the phenotype of the sample. Data were analysed by use of robust statistical multi-way procedures. Results Besides main effects of age, gender, informant, and centre, there were considerable interaction effects on questionnaire data. The larger differences between probands and siblings at home than at school may reflect contrast effects in the parents. Furthermore, there were marked gender by status effects on the ADHD symptom ratings with girls scoring one standard deviation higher than boys in the proband sample but lower than boys in the siblings sample. The multi-centre design is another important source of heterogeneity, particularly in the interaction with the family status. To a large extent the centres differed from each other with regard to differences between proband and sibling scores. Conclusions When ADHD probands are diagnosed by use of fixed symptom counts, the severity of the disorder in the proband sample may markedly differ between boys and girls and across age, particularly in samples with a large age range. A multi-centre design carries the risk of considerable phenotypic differences between centres and, consequently, of additional heterogeneity of the sample even if standardized diagnostic procedures are

The impact of study design and diagnostic approach in a large multi-centre ADHD study: Part 2: Dimensional measures of psychopathology and intelligence.

LENUS (Irish Health Repository)

Muller, Ueli C

2011-04-07

Abstract Background The International Multi-centre ADHD Genetics (IMAGE) project with 11 participating centres from 7 European countries and Israel has collected a large behavioural and genetic database for present and future research. Behavioural data were collected from 1068 probands with ADHD and 1446 unselected siblings. The aim was to describe and analyse questionnaire data and IQ measures from all probands and siblings. In particular, to investigate the influence of age, gender, family status (proband vs. sibling), informant, and centres on sample homogeneity in psychopathological measures. Methods Conners\\' Questionnaires, Strengths and Difficulties Questionnaires, and Wechsler Intelligence Scores were used to describe the phenotype of the sample. Data were analysed by use of robust statistical multi-way procedures. Results Besides main effects of age, gender, informant, and centre, there were considerable interaction effects on questionnaire data. The larger differences between probands and siblings at home than at school may reflect contrast effects in the parents. Furthermore, there were marked gender by status effects on the ADHD symptom ratings with girls scoring one standard deviation higher than boys in the proband sample but lower than boys in the siblings sample. The multi-centre design is another important source of heterogeneity, particularly in the interaction with the family status. To a large extent the centres differed from each other with regard to differences between proband and sibling scores. Conclusions When ADHD probands are diagnosed by use of fixed symptom counts, the severity of the disorder in the proband sample may markedly differ between boys and girls and across age, particularly in samples with a large age range. A multi-centre design carries the risk of considerable phenotypic differences between centres and, consequently, of additional heterogeneity of the sample even if standardized diagnostic procedures are used. These

Accounting for multiple births in randomised trials: a systematic review.

Science.gov (United States)

Yelland, Lisa Nicole; Sullivan, Thomas Richard; Makrides, Maria

2015-03-01

Multiple births are an important subgroup to consider in trials aimed at reducing preterm birth or its consequences. Including multiples results in a unique mixture of independent and clustered data, which has implications for the design, analysis and reporting of the trial. We aimed to determine how multiple births were taken into account in the design and analysis of recent trials involving preterm infants, and whether key information relevant to multiple births was reported. We conducted a systematic review of multicentre randomised trials involving preterm infants published between 2008 and 2013. Information relevant to multiple births was extracted. Of the 56 trials included in the review, 6 (11%) excluded multiples and 24 (43%) failed to indicate whether multiples were included. Among the 26 trials that reported multiples were included, only one (4%) accounted for clustering in the sample size calculations and eight (31%) took the clustering into account in the analysis of the primary outcome. Of the 20 trials that randomised infants, 12 (60%) failed to report how infants from the same birth were randomised. Information on multiple births is often poorly reported in trials involving preterm infants, and clustering due to multiple births is rarely taken into account. Since ignoring clustering could result in inappropriate recommendations for clinical practice, clustering should be taken into account in the design and analysis of future neonatal and perinatal trials including infants from a multiple birth. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The Effect of Using Assessment Instruments on Substance-abuse Outpatients' Adherence to Treatment: a Multi-centre Randomised Controlled Trial

Directory of Open Access Journals (Sweden)

Broekaert Eric

2011-05-01

Full Text Available Abstract Background Drop-out is an important problem in the treatment of substance use disorder. The focus of this study was to investigate the effectiveness of within treatment assessment with feedback directly to patients with multiple substance use disorder on outpatient individual treatment adherence. Feedback consisted of personal resources' and readiness to change status and progress that facilitate or hinder change, thereby using graphical representation. Methods Informed consent was obtained from both the control and experimental groups to be involved in research and follow-up. Following Zelen's single consent design, baseline participants (n = 280 were randomised (sample-size-estimation: 80%power, p=.05, 2-sided and treatment consent was obtained from those allocated to the experiment (n = 142. In both groups, equal numbers of patients did not attend sessions after allocation. So, 227 persons were analyzed according to intention-to-treat analysis (ITT: experiment n = 116;control n = 111. Excluding refusals 211 participants remained for per-protocol analysis (PP: experiment n = 100; control n = 111, The study was conducted in five outpatient treatment-centres of a large network (De Sleutel in Belgium. Participants were people with multiple substance use disorder -abuse and dependence- who had asked for treatment and who had been advised to start individual treatment after a standardised admission assessment with the European Addiction Severity Index. The experimental condition consisted of informing the patient about the intervention and of subsequent assessments plus feedback following a protocol within the first seven sessions. Assessments were made with the Readiness to Change Questionnaire and the Personal Resources Diagnostic System. The control group received the usual treatment without within treatment assessment with feedback. The most important outcome measure in this analysis of the study was the level of adherence to treatment

Evaluator-blinded trial evaluating nurse-led immunotherapy DEcision Coaching In persons with relapsing-remitting Multiple Sclerosis (DECIMS) and accompanying process evaluation: study protocol for a cluster randomised controlled trial.

Science.gov (United States)

Rahn, Anne Christin; Köpke, Sascha; Kasper, Jürgen; Vettorazzi, Eik; Mühlhauser, Ingrid; Heesen, Christoph

2015-03-21

Multiple sclerosis is a chronic neurological condition usually starting in early adulthood and regularly leading to severe disability. Immunotherapy options are growing in number and complexity, while costs of treatments are high and adherence rates remain low. Therefore, treatment decision-making has become more complex for patients. Structured decision coaching, based on the principles of evidence-based patient information and shared decision-making, has the potential to facilitate participation of individuals in the decision-making process. This cluster randomised controlled trial follows the assumption that decision coaching by trained nurses, using evidence-based patient information and preference elicitation, will facilitate informed choices and induce higher decision quality, as well as better decisional adherence. The decision coaching programme will be evaluated through an evaluator-blinded superiority cluster randomised controlled trial, including 300 patients with suspected or definite relapsing-remitting multiple sclerosis, facing an immunotherapy decision. The clusters are 12 multiple sclerosis outpatient clinics in Germany. Further, the trial will be accompanied by a mixed-methods process evaluation and a cost-effectiveness study. Nurses in the intervention group will be trained in shared decision-making, coaching, and evidence-based patient information principles. Patients who meet the inclusion criteria will receive decision coaching (intervention group) with up to three face-to-face coaching sessions with a trained nurse (decision coach) or counselling as usual (control group). Patients in both groups will be given access to an evidence-based online information tool. The primary outcome is 'informed choice' after six months, assessed with the multi-dimensional measure of informed choice including the sub-dimensions risk knowledge (questionnaire), attitude concerning immunotherapy (questionnaire), and immunotherapy uptake (telephone survey

Does the effect of one-day simulation team training in obstetric emergencies decline within one year? A post-hoc analysis of a multicentre cluster randomised controlled trial

NARCIS (Netherlands)

van de Ven, J.; Fransen, A F; Schuit, E.; van Runnard Heimel, P.J.; Mol, Ben W.; Oei, Swan G.

2017-01-01

Does the effect of one-day simulation team training in obstetric emergencies decline within one year? A post-hoc analysis of a multicentre cluster randomised controlled trial. J van de Ven, AF Fransen, E Schuit, PJ van Runnard Heimel, BW Mol, SG Oei Objective To investigate whether the effect of a

MCBT: Multi-Hop Cluster Based Stable Backbone Trees for Data Collection and Dissemination in WSNs

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Tae-Jin Lee

2009-07-01

Full Text Available We propose a stable backbone tree construction algorithm using multi-hop clusters for wireless sensor networks (WSNs. The hierarchical cluster structure has advantages in data fusion and aggregation. Energy consumption can be decreased by managing nodes with cluster heads. Backbone nodes, which are responsible for performing and managing multi-hop communication, can reduce the communication overhead such as control traffic and minimize the number of active nodes. Previous backbone construction algorithms, such as Hierarchical Cluster-based Data Dissemination (HCDD and Multicluster, Mobile, Multimedia radio network (MMM, consume energy quickly. They are designed without regard to appropriate factors such as residual energy and degree (the number of connections or edges to other nodes of a node for WSNs. Thus, the network is quickly disconnected or has to reconstruct a backbone. We propose a distributed algorithm to create a stable backbone by selecting the nodes with higher energy or degree as the cluster heads. This increases the overall network lifetime. Moreover, the proposed method balances energy consumption by distributing the traffic load among nodes around the cluster head. In the simulation, the proposed scheme outperforms previous clustering schemes in terms of the average and the standard deviation of residual energy or degree of backbone nodes, the average residual energy of backbone nodes after disseminating the sensed data, and the network lifetime.

A multi-centre dosimetry audit on advanced radiotherapy in lung as part of the Isotoxic IMRT study

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Yat Tsang

2017-10-01

Conclusion: This multi-centre dosimetry audit of complex IMRT/VMAT delivery provides confidence in the accuracy of modern planning and delivery systems in inhomogeneous tissues. The findings from this study can be used as a reference for future dosimetry audits.

Acute Whiplash Injury Study (AWIS): a protocol for a cluster randomised pilot and feasibility trial of an Active Behavioural Physiotherapy Intervention in an insurance private setting

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Wiangkham, Taweewat; Duda, Joan; Haque, M Sayeed; Price, Jonathan; Rushton, Alison

2016-01-01

Introduction Whiplash-associated disorder (WAD) causes substantial social and economic burden internationally. Up to 60% of patients with WAD progress to chronicity. Research therefore needs to focus on effective management in the acute stage to prevent the development of chronicity. Approximately 93% of patients are classified as WADII (neck complaint and musculoskeletal sign(s)), and in the UK, most are managed in the private sector. In our recent systematic review, a combination of active and behavioural physiotherapy was identified as potentially effective in the acute stage. An Active Behavioural Physiotherapy Intervention (ABPI) was developed through combining empirical (modified Delphi study) and theoretical (social cognitive theory focusing on self-efficacy) evidence. This pilot and feasibility trial has been designed to inform the design of an adequately powered definitive randomised controlled trial. Methods and analysis Two parallel phases. (1) An external pilot and feasibility cluster randomised double-blind (assessor and participants), parallel two-arm (ABPI vs standard physiotherapy) clinical trial to evaluate procedures and feasibility. Six UK private physiotherapy clinics will be recruited and cluster randomised by a computer-generated randomisation sequence. Sixty participants (30 each arm) will be assessed at recruitment (baseline) and at 3 months postbaseline. The planned primary outcome measure is the neck disability index. (2) An embedded exploratory qualitative study using semistructured indepth interviews (n=3–4 physiotherapists) and a focus group (n=6–8 patients) and entailing the recruitment of purposive samples will explore perceptions of the ABPI. Quantitative data will be analysed descriptively. Qualitative data will be coded and analysed deductively (identify themes) and inductively (identify additional themes). Ethics and dissemination This trial is approved by the University of Birmingham Ethics Committee (ERN_15-0542). Trial

A multi-centre evaluation of oral cancer in Southern and Western Nigeria: an African oral pathology research consortium initiative.

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Omitola, Olufemi Gbenga; Soyele, Olujide Oladele; Sigbeku, Opeyemi; Okoh, Dickson; Akinshipo, Abdulwarith Olaitan; Butali, Azeez; Adeola, Henry Ademola

2017-01-01

Oral cancer is a leading cause of cancer deaths among African populations. Lack of standard cancer registries and under-reporting has inaccurately depicted its magnitude in Nigeria. Development of multi-centre collaborative oral pathology networks such as the African Oral Pathology Research Consortium (AOPRC) facilitates skill and expertise exchange and fosters a robust and systematic investigation of oral diseases across Africa. In this descriptive cross-sectional study, we have leveraged the auspices of the AOPRC to examine the burden of oral cancer in Nigeria, using a multi-centre approach. Data from 4 major tertiary health institutions in Western and Southern Nigeria was generated using a standardized data extraction format and analysed using the SPSS data analysis software (version 20.0; SPSS Inc. Chicago, IL). Of the 162 cases examined across the 4 centres, we observed that oral squamous cell carcinomas (OSCC) occurred mostly in the 6 th and 7 th decades of life and maxillary were more frequent than mandibular OSCC lesions. Regional variations were observed both for location, age group and gender distribution. Significant regional differences was found between poorly, moderately and well differentiated OSCC (p value = 0.0071). A multi-centre collaborative oral pathology research approach is an effective way to achieve better insight into the patterns and distribution of various oral diseases in men of African descent. The wider outlook for AOPRC is to employ similar approaches to drive intensive oral pathology research targeted at addressing the current morbidity and mortality of various oral diseases across Africa.

Group art therapy as an adjunctive treatment for people with schizophrenia: a randomised controlled trial (MATISSE).

OpenAIRE

Crawford, MJ; Killaspy, H; Barnes, TR; Barrett, B; Byford, S; Clayton, K; Dinsmore, J; Floyd, S; Hoadley, A; Johnson, T; Kalaitzaki, E; King, M; Leurent, B; Maratos, A; O'Neill, FA

2012-01-01

OBJECTIVE To examine the clinical effectiveness and cost-effectiveness of referral to group art therapy plus standard care, compared with referral to an activity group plus standard care and standard care alone, among people with schizophrenia. DESIGN A three-arm, parallel group, single-blind, pragmatic, randomised controlled trial. Participants were randomised via an independent and remote telephone randomisation service using permuted blocks, stratified by study centre. SETTING Study partic...

A cluster-randomised quality improvement study to improve two inpatient stroke quality indicators.

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Williams, Linda; Daggett, Virginia; Slaven, James E; Yu, Zhangsheng; Sager, Danielle; Myers, Jennifer; Plue, Laurie; Woodward-Hagg, Heather; Damush, Teresa M

2016-04-01

Quality indicator collection and feedback improves stroke care. We sought to determine whether quality improvement training plus indicator feedback was more effective than indicator feedback alone in improving inpatient stroke indicators. We conducted a cluster-randomised quality improvement trial, randomising hospitals to quality improvement training plus indicator feedback versus indicator feedback alone to improve deep vein thrombosis (DVT) prophylaxis and dysphagia screening. Intervention sites received collaborative-based quality improvement training, external facilitation and indicator feedback. Control sites received only indicator feedback. We compared indicators pre-implementation (pre-I) to active implementation (active-I) and post-implementation (post-I) periods. We constructed mixed-effect logistic models of the two indicators with a random intercept for hospital effect, adjusting for patient, time, intervention and hospital variables. Patients at intervention sites (1147 admissions), had similar race, gender and National Institutes of Health Stroke Scale scores to control sites (1017 admissions). DVT prophylaxis improved more in intervention sites during active-I period (ratio of ORs 4.90, pimproved similarly in both groups during active-I, but control sites improved more in post-I period (ratio of ORs 0.67, p=0.04). In logistic models, the intervention was independently positively associated with DVT performance during active-I period, and negatively associated with dysphagia performance post-I period. Quality improvement training was associated with early DVT improvement, but the effect was not sustained over time and was not seen with dysphagia screening. External quality improvement programmes may quickly boost performance but their effect may vary by indicator and may not sustain over time. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

A multi-centre open-label randomised non-inferiority trial comparing watchful waiting to antibiotic treatment for acute otitis media without perforation in low-risk urban Aboriginal and Torres Strait Islander children (the WATCH trial): study protocol for a randomised controlled trial.

Science.gov (United States)

Abbott, Penelope; Gunasekera, Hasantha; Leach, Amanda Jane; Askew, Deborah; Walsh, Robyn; Kong, Kelvin; Girosi, Federico; Bond, Chelsea; Morris, Peter; Lujic, Sanja; Hu, Wendy; Usherwood, Tim; Tyson, Sissy; Spurling, Geoffrey; Douglas, Markeeta; Schubert, Kira; Chapman, Shavaun; Siddiqui, Nadeem; Murray, Reeion; Rabbitt, Keitha; Porykali, Bobby; Woodall, Cheryl; Newman, Tina; Reath, Jennifer

2016-03-03

Treatment guidelines recommend watchful waiting for children older than 2 years with acute otitis media (AOM) without perforation, unless they are at high risk of complications. The high prevalence of chronic suppurative otitis media (CSOM) in remote Aboriginal and Torres Strait Islander communities leads these children to be classified as high risk. Urban Aboriginal and Torres Strait Islander children are at lower risk of complications, but evidence to support the subsequent recommendation for watchful waiting in this population is lacking. This non-inferiority multi-centre randomised controlled trial will determine whether watchful waiting is non-inferior to immediate antibiotics for urban Aboriginal and Torres Strait Islander children with AOM without perforation. Children aged 2 - 16 years with AOM who are considered at low risk for complications will be recruited from six participating urban primary health care services across Australia. We will obtain informed consent from each participant or their guardian. The primary outcome is clinical resolution on day 7 (no pain, no fever of at least 38 °C, no bulging eardrum and no complications of AOM such as perforation or mastoiditis) as assessed by general practitioners or nurse practitioners. Participants and outcome assessors will not be blinded to treatment. With a sample size of 198 children in each arm, we have 80 % power to detect a non-inferiority margin of up to 10 % at a significance level of 5 %, assuming clinical improvement of at least 80 % in both groups. Allowing for a 20 % dropout rate, we aim to recruit 495 children. We will analyse both by intention-to-treat and per protocol. We will assess the cost- effectiveness of watchful waiting compared to immediate antibiotic prescription. We will also report on the implementation of the trial from the perspectives of parents/carers, health professionals and researchers. The trial will provide evidence for the safety and effectiveness of watchful waiting

Comparative cost-effectiveness of two interventions to promote work functioning by targeting mental health complaints among nurses: pragmatic cluster randomised trial.

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Noben, Cindy; Smit, Filip; Nieuwenhuijsen, Karen; Ketelaar, Sarah; Gärtner, Fania; Boon, Brigitte; Sluiter, Judith; Evers, Silvia

2014-10-01

The specific job demands of working in a hospital may place nurses at elevated risk for developing distress, anxiety and depression. Screening followed by referral to early interventions may reduce the incidence of these health problems and promote work functioning. To evaluate the comparative cost-effectiveness of two strategies to promote work functioning among nurses by reducing symptoms of mental health complaints. Three conditions were compared: the control condition consisted of online screening for mental health problems without feedback about the screening results. The occupational physician condition consisted of screening, feedback and referral to the occupational physician for screen-positive nurses. The third condition included screening, feedback, and referral to e-mental health. The study was designed as an economic evaluation alongside a pragmatic cluster randomised controlled trial with randomisation at hospital-ward level. The study included 617 nurses in one academic medical centre in the Netherlands. Treatment response was defined as an improvement on the Nurses Work Functioning Questionnaire of at least 40% between baseline and follow-up. Total per-participant costs encompassed intervention costs, direct medical and non-medical costs, and indirect costs stemming from lost productivity due to absenteeism and presenteeism. All costs were indexed for the year 2011. At 6 months follow-up, significant improvement in work functioning occurred in 20%, 24% and 16% of the participating nurses in the control condition, the occupational physician condition and the e-mental health condition, respectively. In these conditions the total average annualised costs were €1752, €1266 and €1375 per nurse. The median incremental cost-effectiveness ratio for the occupational physician condition versus the control condition was dominant, suggesting cost savings of €5049 per treatment responder. The incremental cost-effectiveness ratio for the e-mental health

A cluster randomised controlled trial of an intervention to promote healthy lifestyle habits to school leavers: study rationale, design, and methods.

Science.gov (United States)

Gillison, Fiona; Standage, Martyn; Verplanken, Bas

2014-03-04

Physical inactivity and a poor diet predict lifestyle diseases such as diabetes, cardiovascular disease, and certain types of cancer. Marked declines in physical activity occur during late adolescence, coinciding with the point at which many young people leave school and enter the workforce and begin to take greater control over their lifestyle behaviours. The work outlined within this paper sought to test a theoretically-informed intervention aimed at supporting increased engagement in physical activity and healthy eating habits in young people at the point of transition from school to work or work-based learning. As actively engaging young people in initiatives based on health messages is challenging, we also tested the efficacy of financial incentives in promoting initial engagement with the programme. A three-arm cluster-randomised design was used. Participants were school pupils from Year 11 and 13 (i.e., in their final year of study), aged 16-18 years. To reduce contamination effects, the unit of randomisation was school. Participants were randomly allocated to receive (i) a 12-week behavioural support intervention consisting of six appointments, (ii) a behavioural support intervention plus incentives (totalling £40), or (iii) an information-only control group. Behavioural support was provided by fitness advisors at local leisure centres following an initial consultation with a dietician. Sessions focused on promoting habit formation through setting implementation intentions as part of an incremental goal setting process. Consistent with self-determination theory, all advisors were trained to provide guidance in an autonomy-supportive manner so that they were equipped to create a social context supportive of autonomous forms of participant motivation. The primary outcome was objectively assessed physical activity (via GT1M accelerometers). Secondary outcome measures were diet, motivation and habit strength. Data were collected at baseline, post

Pathways: patient-centred decision counselling for women at risk of cancer-related infertility: a protocol for a comparative effectiveness cluster randomised trial.

Science.gov (United States)

Woodard, Terri Lynn; Hoffman, Aubri S; Crocker, Laura C; Holman, Deborah A; Hoffman, Derek B; Ma, Jusheng; Bassett, Roland L; Leal, Viola B; Volk, Robert J

2018-02-21

National guidelines recommend that all reproductive-age women with cancer be informed of their fertility risks and offered referral to fertility specialists to discuss fertility preservation options. However, reports indicate that only 5% of patients have consultations, and rates of long-term infertility-related distress remain high. Previous studies report several barriers to fertility preservation; however, initial success has been reported using provider education, patient decision aids and navigation support. This protocol will test effects of a multicomponent intervention compared with usual care on women's fertility preservation knowledge and decision-making outcomes. This cluster-randomised trial will compare the multicomponent intervention (provider education, patient decision aid and navigation support) with usual care (consultation and referral, if requested). One hundred newly diagnosed English-speaking women of reproductive age who are at risk of cancer-related infertility will be recruited from four regional oncology clinics.The Pathways patient decision aid website provides (1) up-to-date evidence and descriptions of fertility preservation and other family-building options, tailored to cancer type; (2) structured guidance to support personalising the information and informed decision-making; and (3) a printable summary to help women prepare for discussions with their oncologist and/or fertility specialist. Four sites will be randomly assigned to intervention or control groups. Participants will be recruited after their oncology consultation and asked to complete online questionnaires at baseline, 1 week and 2 months to assess their demographics, fertility preservation knowledge, and decision-making process and quality. The primary outcome (decisional conflict) will be tested using Fisher's exact test. Secondary outcomes will be assessed using generalised linear mixed models, and sensitivity analyses will be conducted, as appropriate. The University of

Applying Stochastic Metaheuristics to the Problem of Data Management in a Multi-Tenant Database Cluster

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E. A. Boytsov

2014-01-01

Full Text Available A multi-tenant database cluster is a concept of a data-storage subsystem for cloud applications with the multi-tenant architecture. The cluster is a set of relational database servers with the single entry point, combined into one unit with a cluster controller. This system is aimed to be used by applications developed according to Software as a Service (SaaS paradigm and allows to place tenants at database servers so that providing their isolation, data backup and the most effective usage of available computational power. One of the most important problems about such a system is an effective distribution of data into servers, which affects the degree of individual cluster nodes load and faulttolerance. This paper considers the data-management approach, based on the usage of a load-balancing quality measure function. This function is used during initial placement of new tenants and also during placement optimization steps. Standard schemes of metaheuristic optimization such as simulated annealing and tabu search are used to find a better tenant placement.

Evaluation of an Australian health literacy training program for socially disadvantaged adults attending basic education classes: study protocol for a cluster randomised controlled trial.

Science.gov (United States)

McCaffery, Kirsten J; Morony, Suzanne; Muscat, Danielle M; Smith, Sian K; Shepherd, Heather L; Dhillon, Haryana M; Hayen, Andrew; Luxford, Karen; Meshreky, Wedyan; Comings, John; Nutbeam, Don

2016-05-27

People with low literacy and low health literacy have poorer health outcomes. Literacy and health literacy are distinct but overlapping constructs that impact wellbeing. Interventions that target both could improve health outcomes. This is a cluster randomised controlled trial with a qualitative component. Participants are 300 adults enrolled in basic language, literacy and numeracy programs at adult education colleges across New South Wales, Australia. Each adult education institute (regional administrative centre) contributes (at least) two classes matched for student demographics, which may be at the same or different campuses. Classes (clusters) are randomly allocated to receive either the health literacy intervention (an 18-week program with health knowledge and skills embedded in language, literacy, and numeracy training (LLN)), or the standard Language Literacy and Numeracy (LLN) program (usual LLN classes, specifically excluding health content). The primary outcome is functional health literacy skills - knowing how to use a thermometer, and read and interpret food and medicine labels. The secondary outcomes are self-reported confidence, more advanced health literacy skills; shared decision making skills, patient activation, health knowledge and self-reported health behaviour. Data is collected at baseline, and immediately and 6 months post intervention. A sample of participating teachers, students, and community health workers will be interviewed in-depth about their experiences with the program to better understand implementation issues and to strengthen the potential for scaling up the program. Outcomes will provide evidence regarding real-world implementation of a health literacy training program with health worker involvement in an Australian adult education setting. The evaluation trial will provide insight into translating and scaling up health literacy education for vulnerable populations with low literacy. Australian New Zealand Clinical Trials

Computerized detection of breast lesions in multi-centre and multi-instrument DCE-MR data using 3D principal component maps and template matching

Science.gov (United States)

Ertas, Gokhan; Doran, Simon; Leach, Martin O.

2011-12-01

In this study, we introduce a novel, robust and accurate computerized algorithm based on volumetric principal component maps and template matching that facilitates lesion detection on dynamic contrast-enhanced MR. The study dataset comprises 24 204 contrast-enhanced breast MR images corresponding to 4034 axial slices from 47 women in the UK multi-centre study of MRI screening for breast cancer and categorized as high risk. The scans analysed here were performed on six different models of scanner from three commercial vendors, sited in 13 clinics around the UK. 1952 slices from this dataset, containing 15 benign and 13 malignant lesions, were used for training. The remaining 2082 slices, with 14 benign and 12 malignant lesions, were used for test purposes. To prevent false positives being detected from other tissues and regions of the body, breast volumes are segmented from pre-contrast images using a fast semi-automated algorithm. Principal component analysis is applied to the centred intensity vectors formed from the dynamic contrast-enhanced T1-weighted images of the segmented breasts, followed by automatic thresholding to eliminate fatty tissues and slowly enhancing normal parenchyma and a convolution and filtering process to minimize artefacts from moderately enhanced normal parenchyma and blood vessels. Finally, suspicious lesions are identified through a volumetric sixfold neighbourhood connectivity search and calculation of two morphological features: volume and volumetric eccentricity, to exclude highly enhanced blood vessels, nipples and normal parenchyma and to localize lesions. This provides satisfactory lesion localization. For a detection sensitivity of 100%, the overall false-positive detection rate of the system is 1.02/lesion, 1.17/case and 0.08/slice, comparing favourably with previous studies. This approach may facilitate detection of lesions in multi-centre and multi-instrument dynamic contrast-enhanced breast MR data.

Riemannian multi-manifold modeling and clustering in brain networks

Science.gov (United States)

Slavakis, Konstantinos; Salsabilian, Shiva; Wack, David S.; Muldoon, Sarah F.; Baidoo-Williams, Henry E.; Vettel, Jean M.; Cieslak, Matthew; Grafton, Scott T.

2017-08-01

This paper introduces Riemannian multi-manifold modeling in the context of brain-network analytics: Brainnetwork time-series yield features which are modeled as points lying in or close to a union of a finite number of submanifolds within a known Riemannian manifold. Distinguishing disparate time series amounts thus to clustering multiple Riemannian submanifolds. To this end, two feature-generation schemes for brain-network time series are put forth. The first one is motivated by Granger-causality arguments and uses an auto-regressive moving average model to map low-rank linear vector subspaces, spanned by column vectors of appropriately defined observability matrices, to points into the Grassmann manifold. The second one utilizes (non-linear) dependencies among network nodes by introducing kernel-based partial correlations to generate points in the manifold of positivedefinite matrices. Based on recently developed research on clustering Riemannian submanifolds, an algorithm is provided for distinguishing time series based on their Riemannian-geometry properties. Numerical tests on time series, synthetically generated from real brain-network structural connectivity matrices, reveal that the proposed scheme outperforms classical and state-of-the-art techniques in clustering brain-network states/structures.

Screening and brief interventions for hazardous and harmful alcohol use in probation services: a cluster randomised controlled trial protocol

Directory of Open Access Journals (Sweden)

Myles Judy

2009-11-01

Full Text Available Abstract Background A large number of randomised controlled trials in health settings have consistently reported positive effects of brief intervention in terms of reductions in alcohol use. However, although alcohol misuse is common amongst offenders, there is limited evidence of alcohol brief interventions in the criminal justice field. This factorial pragmatic cluster randomised controlled trial with Offender Managers (OMs as the unit of randomisation will evaluate the effectiveness and cost-effectiveness of different models of screening to identify hazardous and harmful drinkers in probation and different intensities of brief intervention to reduce excessive drinking in probation clients. Methods and design Ninety-six OMs from 9 probation areas across 3 English regions (the North East Region (n = 4 and London and the South East Regions (n = 5 will be recruited. OMs will be randomly allocated to one of three intervention conditions: a client information leaflet control condition (n = 32 OMs; 5-minute simple structured advice (n = 32 OMs and 20-minute brief lifestyle counselling delivered by an Alcohol Health Worker (n = 32 OMs. Randomisation will be stratified by probation area. To test the relative effectiveness of different screening methods all OMs will be randomised to either the Modified Single Item Screening Questionnaire (M-SASQ or the Fast Alcohol Screening Test (FAST. There will be a minimum of 480 clients recruited into the trial. There will be an intention to treat analysis of study outcomes at 6 and 12 months post intervention. Analysis will include client measures (screening result, weekly alcohol consumption, alcohol-related problems, re-offending, public service use and quality of life and implementation measures from OMs (the extent of screening and brief intervention beyond the minimum recruitment threshold will provide data on acceptability and feasibility of different models of brief intervention. We will also examine the

Screening and brief interventions for hazardous and harmful alcohol use in probation services: a cluster randomised controlled trial protocol.

Science.gov (United States)

Newbury-Birch, Dorothy; Bland, Martin; Cassidy, Paul; Coulton, Simon; Deluca, Paolo; Drummond, Colin; Gilvarry, Eilish; Godfrey, Christine; Heather, Nick; Kaner, Eileen; Myles, Judy; Oyefeso, Adenekan; Parrott, Steve; Perryman, Katherine; Phillips, Tom; Shenker, Don; Shepherd, Jonathan

2009-11-18

A large number of randomised controlled trials in health settings have consistently reported positive effects of brief intervention in terms of reductions in alcohol use. However, although alcohol misuse is common amongst offenders, there is limited evidence of alcohol brief interventions in the criminal justice field. This factorial pragmatic cluster randomised controlled trial with Offender Managers (OMs) as the unit of randomisation will evaluate the effectiveness and cost-effectiveness of different models of screening to identify hazardous and harmful drinkers in probation and different intensities of brief intervention to reduce excessive drinking in probation clients. Ninety-six OMs from 9 probation areas across 3 English regions (the North East Region (n = 4) and London and the South East Regions (n = 5)) will be recruited. OMs will be randomly allocated to one of three intervention conditions: a client information leaflet control condition (n = 32 OMs); 5-minute simple structured advice (n = 32 OMs) and 20-minute brief lifestyle counselling delivered by an Alcohol Health Worker (n = 32 OMs). Randomisation will be stratified by probation area. To test the relative effectiveness of different screening methods all OMs will be randomised to either the Modified Single Item Screening Questionnaire (M-SASQ) or the Fast Alcohol Screening Test (FAST). There will be a minimum of 480 clients recruited into the trial. There will be an intention to treat analysis of study outcomes at 6 and 12 months post intervention. Analysis will include client measures (screening result, weekly alcohol consumption, alcohol-related problems, re-offending, public service use and quality of life) and implementation measures from OMs (the extent of screening and brief intervention beyond the minimum recruitment threshold will provide data on acceptability and feasibility of different models of brief intervention). We will also examine the practitioner and organisational factors

Energy Efficient Clustering in Multi-hop Wireless Sensor Networks Using Differential Evolutionary MOPSO

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D. Rajendra Prasad

Full Text Available ABSTRACT The primary challenge in organizing sensor networks is energy efficacy. This requisite for energy efficacy is because sensor nodes capacities are limited and replacing them is not viable. This restriction further decreases network lifetime. Node lifetime varies depending on the requisites expected of its battery. Hence, primary element in constructing sensor networks is resilience to deal with decreasing lifetime of all sensor nodes. Various network infrastructures as well as their routing protocols for reduction of power utilization as well as to prolong network lifetime are studied. After analysis, it is observed that network constructions that depend on clustering are the most effective methods in terms of power utilization. Clustering divides networks into inter-related clusters such that every cluster has several sensor nodes with a Cluster Head (CH at its head. Sensor gathered information is transmitted to data processing centers through CH hierarchy in clustered environments. The current study utilizes Multi-Objective Particle Swarm Optimization (MOPSO-Differential Evolution (DE (MOPSO-DE technique for optimizing clustering.

Study protocol: a cluster randomised controlled trial of a school based fruit and vegetable intervention - Project Tomato.

Science.gov (United States)

Kitchen, Meaghan S; Ransley, Joan K; Greenwood, Darren C; Clarke, Graham P; Conner, Mark T; Jupp, Jennifer; Cade, Janet E

2009-06-16

The School Fruit and Vegetable Scheme (SFVS) is an important public health intervention. The aim of this scheme is to provide a free piece of fruit and/or vegetable every day for children in Reception to Year 2. When children are no longer eligible for the scheme (from Year 3) their overall fruit and vegetable consumption decreases back to baseline levels. This proposed study aims to design a flexible multi-component intervention for schools to support the maintenance of fruit and vegetable consumption for Year 3 children who are no longer eligible for the scheme. This study is a cluster randomised controlled trial of Year 2 classes from 54 primary schools across England. The schools will be randomly allocated into two groups to receive either an active intervention called Project Tomato, to support maintenance of fruit intake in Year 3 children, or a less active intervention (control group), consisting of a 5 A DAY booklet. Children's diets will be analysed using the Child And Diet Evaluation Tool (CADET), and height and weight measurements collected, at baseline (Year 2) and 18 month follow-up (Year 4). The primary outcome will be the ability of the intervention (Project Tomato) to maintain consumption of fruit and vegetable portions compared to the control group. A positive result will identify how fruit and vegetable consumption can be maintained in young children, and will be useful for policies supporting the SFVS. A negative result would be used to inform the research agenda and contribute to redefining future strategies for increasing children's fruit and vegetable consumption. Medical Research Council Registry code G0501297.

Growth effects of exclusive breastfeeding promotion by peer counsellors in sub-Saharan Africa: the cluster-randomised PROMISE EBF trial.

Science.gov (United States)

Engebretsen, Ingunn Marie Stadskleiv; Jackson, Debra; Fadnes, Lars Thore; Nankabirwa, Victoria; Diallo, Abdoulaye Hama; Doherty, Tanya; Lombard, Carl; Swanvelder, Sonja; Nankunda, Jolly; Ramokolo, Vundli; Sanders, David; Wamani, Henry; Meda, Nicolas; Tumwine, James K; Ekström, Eva-Charlotte; Van de Perre, Philippe; Kankasa, Chipepo; Sommerfelt, Halvor; Tylleskär, Thorkild

2014-06-21

In this multi-country cluster-randomized behavioural intervention trial promoting exclusive breastfeeding (EBF) in Africa, we compared growth of infants up to 6 months of age living in communities where peer counsellors promoted EBF with growth in those infants living in control communities. A total of 82 clusters in Burkina Faso, Uganda and South Africa were randomised to either the intervention or the control arm. Feeding data and anthropometric measurements were collected at visits scheduled 3, 6, 12 and 24 weeks post-partum. We calculated weight-for-length (WLZ), length-for-age (LAZ) and weight-for-age (WAZ) z-scores. Country specific adjusted Least Squares Means with 95% confidence intervals (CI) based on a longitudinal analysis are reported. Prevalence ratios (PR) for the association between peer counselling for EBF and wasting (WLZ economic status, the mean WLZ at 24 weeks were in Burkina Faso -0.20 (95% CI -0.39 to -0.01) and in Uganda -0.23 (95% CI -0.43 to -0.03) lower in the intervention than in the control arm. In South Africa the mean WLZ at 24 weeks was 0.23 (95% CI 0.03 to 0.43) greater in the intervention than in the control arm. Differences in LAZ between the study arms were small and not statistically significant. In Uganda, infants in the intervention arm were more likely to be wasted compared to those in the control arm at 24 weeks (PR 2.36; 95% CI 1.11 to 5.00). Differences in wasting in South Africa and Burkina Faso and stunting and underweight in all three countries were small and not significantly different. There were small differences in mean anthropometric indicators between the intervention and control arms in the study, but in Uganda and Burkina Faso, a tendency to slightly lower ponderal growth (weight-for-length z-scores) was found in the intervention arms. ClinicalTrials.gov: NCT00397150.

Predictors of primary care referrals to a vascular disease prevention lifestyle program among participants in a cluster randomised trial

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Passey Megan E

2012-08-01

Full Text Available Abstract Background Cardiovascular disease accounts for a large burden of disease, but is amenable to prevention through lifestyle modification. This paper examines patient and practice predictors of referral to a lifestyle modification program (LMP offered as part of a cluster randomised controlled trial (RCT of prevention of vascular disease in primary care. Methods Data from the intervention arm of a cluster RCT which recruited 36 practices through two rural and three urban primary care organisations were used. In each practice, 160 eligible high risk patients were invited to participate. Practices were randomly allocated to intervention or control groups. Intervention practice staff were trained in screening, motivational interviewing and counselling and encouraged to refer high risk patients to a LMP involving individual and group sessions. Data include patient surveys; clinical audit; practice survey on capacity for preventive care; referral records from the LMP. Predictors of referral were examined using multi-level logistic regression modelling after adjustment for confounding factors. Results Of 301 eligible patients, 190 (63.1% were referred to the LMP. Independent predictors of referral were baseline BMI ≥ 25 (OR 2.87 95%CI:1.10, 7.47, physical inactivity (OR 2.90 95%CI:1.36,6.14, contemplation/preparation/action stage of change for physical activity (OR 2.75 95%CI:1.07, 7.03, rural location (OR 12.50 95%CI:1.43, 109.7 and smaller practice size (1–3 GPs (OR 16.05 95%CI:2.74, 94.24. Conclusions Providing a well-structured evidence-based lifestyle intervention, free of charge to patients, with coordination and support for referral processes resulted in over 60% of participating high risk patients being referred for disease prevention. Contrary to expectations, referrals were more frequent from rural and smaller practices suggesting that these practices may be more ready to engage with these programs. Trial registration ACTRN

Effectiveness and cost-effectiveness of a physical activity loyalty scheme for behaviour change maintenance: a cluster randomised controlled trial

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Ruth F. Hunter

2016-07-01

Full Text Available Abstract Background Increasing physical activity in the workplace can provide employee physical and mental health benefits, and employer economic benefits through reduced absenteeism and increased productivity. The workplace is an opportune setting to encourage habitual activity. However, there is limited evidence on effective behaviour change interventions that lead to maintained physical activity. This study aims to address this gap and help build the necessary evidence base for effective, and cost-effective, workplace interventions. Methods/design This cluster randomised control trial will recruit 776 office-based employees from public sector organisations in Belfast and Lisburn city centres, Northern Ireland. Participants will be randomly allocated by cluster to either the Intervention Group or Control Group (waiting list control. The 6-month intervention consists of rewards (retail vouchers, based on similar principles to high street loyalty cards, feedback and other evidence-based behaviour change techniques. Sensors situated in the vicinity of participating workplaces will promote and monitor minutes of physical activity undertaken by participants. Both groups will complete all outcome measures. The primary outcome is steps per day recorded using a pedometer (Yamax Digiwalker CW-701 for 7 consecutive days at baseline, 6, 12 and 18 months. Secondary outcomes include health, mental wellbeing, quality of life, work absenteeism and presenteeism, and use of healthcare resources. Process measures will assess intervention “dose”, website usage, and intervention fidelity. An economic evaluation will be conducted from the National Health Service, employer and retailer perspective using both a cost-utility and cost-effectiveness framework. The inclusion of a discrete choice experiment will further generate values for a cost-benefit analysis. Participant focus groups will explore who the intervention worked for and why, and interviews with

Effectiveness and cost-effectiveness of a physical activity loyalty scheme for behaviour change maintenance: a cluster randomised controlled trial.

Science.gov (United States)

Hunter, Ruth F; Brennan, Sarah F; Tang, Jianjun; Smith, Oliver J; Murray, Jennifer; Tully, Mark A; Patterson, Chris; Longo, Alberto; Hutchinson, George; Prior, Lindsay; French, David P; Adams, Jean; McIntosh, Emma; Kee, Frank

2016-07-22

Increasing physical activity in the workplace can provide employee physical and mental health benefits, and employer economic benefits through reduced absenteeism and increased productivity. The workplace is an opportune setting to encourage habitual activity. However, there is limited evidence on effective behaviour change interventions that lead to maintained physical activity. This study aims to address this gap and help build the necessary evidence base for effective, and cost-effective, workplace interventions. This cluster randomised control trial will recruit 776 office-based employees from public sector organisations in Belfast and Lisburn city centres, Northern Ireland. Participants will be randomly allocated by cluster to either the Intervention Group or Control Group (waiting list control). The 6-month intervention consists of rewards (retail vouchers, based on similar principles to high street loyalty cards), feedback and other evidence-based behaviour change techniques. Sensors situated in the vicinity of participating workplaces will promote and monitor minutes of physical activity undertaken by participants. Both groups will complete all outcome measures. The primary outcome is steps per day recorded using a pedometer (Yamax Digiwalker CW-701) for 7 consecutive days at baseline, 6, 12 and 18 months. Secondary outcomes include health, mental wellbeing, quality of life, work absenteeism and presenteeism, and use of healthcare resources. Process measures will assess intervention "dose", website usage, and intervention fidelity. An economic evaluation will be conducted from the National Health Service, employer and retailer perspective using both a cost-utility and cost-effectiveness framework. The inclusion of a discrete choice experiment will further generate values for a cost-benefit analysis. Participant focus groups will explore who the intervention worked for and why, and interviews with retailers will elucidate their views on the sustainability

Implementing knowledge into practice for improved neonatal survival; a cluster-randomised, community-based trial in Quang Ninh province, Vietnam

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Huy Tran Q

2011-09-01

Full Text Available Abstract Background Globally, almost 4 million newborns die during the first 4 weeks of life every year. By increased use of evidence-based knowledge in the healthcare system a large proportion of these neonatal deaths could be prevented. But there is a severe lack of knowledge on effective methods for successful implementation of evidence into practice, particularly in low- and middle-income countries. Recent studies have demonstrated promising results with increased survival among both mothers and newborns using community-based approaches. In Vietnam evidence-based guidelines on reproductive health were launched in 2003 and revised in 2009. The overall objective of the current project is to evaluate if a facilitation intervention on the community level, with a problem-solving approach involving local representatives if the healthcare system and the community, results in improvements of neonatal health and survival. Methods/Design The study, which has been given the acronym NeoKIP (Neonatal Health - Knowledge Into Practice, took place in 8 districts composed by 90 communes in a province in northern Vietnam, where neonatal mortality rate was 24/1000 in 2005. A cluster randomised design was used, allocating clusters, as defined as a commune and its correponding Commune Health Center (CHC to either intervention or control arm. The facilitation intervention targeted staff at healthcare centres and key persons in the communes. The facilitator role was performed by lay women (Women's Union representatives using quality improvement techniques to initiate and sustain improvement processes targeting identified problem areas. The intervention has been running over 3 years and data were collected on the facilitation process, healthcare staff knowledge in neonatal care and their behaviour in clinical practice, and reproductive and perinatal health indicators. Primary outcome is neonatal mortality. Discussion The intervention is participatory and dynamic

A Multi-Hop Energy Neutral Clustering Algorithm for Maximizing Network Information Gathering in Energy Harvesting Wireless Sensor Networks.

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Yang, Liu; Lu, Yinzhi; Zhong, Yuanchang; Wu, Xuegang; Yang, Simon X

2015-12-26

Energy resource limitation is a severe problem in traditional wireless sensor networks (WSNs) because it restricts the lifetime of network. Recently, the emergence of energy harvesting techniques has brought with them the expectation to overcome this problem. In particular, it is possible for a sensor node with energy harvesting abilities to work perpetually in an Energy Neutral state. In this paper, a Multi-hop Energy Neutral Clustering (MENC) algorithm is proposed to construct the optimal multi-hop clustering architecture in energy harvesting WSNs, with the goal of achieving perpetual network operation. All cluster heads (CHs) in the network act as routers to transmit data to base station (BS) cooperatively by a multi-hop communication method. In addition, by analyzing the energy consumption of intra- and inter-cluster data transmission, we give the energy neutrality constraints. Under these constraints, every sensor node can work in an energy neutral state, which in turn provides perpetual network operation. Furthermore, the minimum network data transmission cycle is mathematically derived using convex optimization techniques while the network information gathering is maximal. Simulation results show that our protocol can achieve perpetual network operation, so that the consistent data delivery is guaranteed. In addition, substantial improvements on the performance of network throughput are also achieved as compared to the famous traditional clustering protocol LEACH and recent energy harvesting aware clustering protocols.

A Multi-Hop Energy Neutral Clustering Algorithm for Maximizing Network Information Gathering in Energy Harvesting Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Liu Yang

2015-12-01

Full Text Available Energy resource limitation is a severe problem in traditional wireless sensor networks (WSNs because it restricts the lifetime of network. Recently, the emergence of energy harvesting techniques has brought with them the expectation to overcome this problem. In particular, it is possible for a sensor node with energy harvesting abilities to work perpetually in an Energy Neutral state. In this paper, a Multi-hop Energy Neutral Clustering (MENC algorithm is proposed to construct the optimal multi-hop clustering architecture in energy harvesting WSNs, with the goal of achieving perpetual network operation. All cluster heads (CHs in the network act as routers to transmit data to base station (BS cooperatively by a multi-hop communication method. In addition, by analyzing the energy consumption of intra- and inter-cluster data transmission, we give the energy neutrality constraints. Under these constraints, every sensor node can work in an energy neutral state, which in turn provides perpetual network operation. Furthermore, the minimum network data transmission cycle is mathematically derived using convex optimization techniques while the network information gathering is maximal. Simulation results show that our protocol can achieve perpetual network operation, so that the consistent data delivery is guaranteed. In addition, substantial improvements on the performance of network throughput are also achieved as compared to the famous traditional clustering protocol LEACH and recent energy harvesting aware clustering protocols.

Multi-agent grid system Agent-GRID with dynamic load balancing of cluster nodes

Science.gov (United States)

Satymbekov, M. N.; Pak, I. T.; Naizabayeva, L.; Nurzhanov, Ch. A.

2017-12-01

In this study the work presents the system designed for automated load balancing of the contributor by analysing the load of compute nodes and the subsequent migration of virtual machines from loaded nodes to less loaded ones. This system increases the performance of cluster nodes and helps in the timely processing of data. A grid system balances the work of cluster nodes the relevance of the system is the award of multi-agent balancing for the solution of such problems.

Protocol for a single-centre, randomised controlled study of a preoperative rehabilitation bundle in the frail and elderly undergoing abdominal surgery.

Science.gov (United States)

Abdullah, Hairil Rizal; Lien, Victoria Peixin; Ong, Hwee Kuan; Er, Pei Ling; Hao, Ying; Khan, Shariq Ali; Liu, Christopher Weiyang

2017-08-04

Frail patients have decreased physiological reserves and consequently, they are unable to recover as quickly from surgery. Frailty, as an entity, is a risk factor of increased morbidity and mortality. It is also associated with a longer time to discharge. This trial is undertaken to determine if a novel prehabilitation protocol (10-day bundle of interventions-physiotherapy, nutritional supplementation and cognitive training) can reduce the postoperative length of stay of frail patients who are undergoing elective abdominal surgery, compared with standard care. This is a prospective, single-centre, randomised controlled trial with two parallel arms. 62 patients who are frail and undergoing elective abdominal surgery will be recruited and randomised to receive either a novel prehabilitation protocol or standard care. Participants will receive telephone reminders preoperatively to encourage protocol compliance. Data will be collected for up to 30 days postoperatively. The primary outcome of the trial will be the postoperative length of stay and the secondary outcomes are the postoperative complications and functional recovery during the hospital admission. This study has been approved by the Singapore General Hospital Institutional Review Board (CIRB Ref: 2016/2584). The study is also listed on ClinicalTrials.gov (Trial number: NCT02921932). All participants will sign an informed consent form before randomisation and translators will be made available to non-English speaking patients. The results of this study will be published in peer-reviewed journals as well as national and international conferences. The data collected will also be made available in a public data repository. NCT02921932 (ClinicalTrials.gov). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Multi-Objective Clustering Optimization for Multi-Channel Cooperative Spectrum Sensing in Heterogeneous Green CRNs

KAUST Repository

Celik, Abdulkadir

2016-06-27

In this paper, we address energy efficient (EE) cooperative spectrum sensing policies for large scale heterogeneous cognitive radio networks (CRNs) which consist of multiple primary channels and large number of secondary users (SUs) with heterogeneous sensing and reporting channel qualities. We approach this issue from macro and micro perspectives. Macro perspective groups SUs into clusters with the objectives: 1) total energy consumption minimization; 2) total throughput maximization; and 3) inter-cluster energy and throughput fairness. We adopt and demonstrate how to solve these using the nondominated sorting genetic algorithm-II. The micro perspective, on the other hand, operates as a sub-procedure on cluster formations decided by the macro perspective. For the micro perspectives, we first propose a procedure to select the cluster head (CH) which yields: 1) the best CH which gives the minimum total multi-hop error rate and 2) the optimal routing paths from SUs to the CH. Exploiting Poisson-Binomial distribution, a novel and generalized K-out-of-N voting rule is developed for heterogeneous CRNs to allow SUs to have different local detection performances. Then, a convex optimization framework is established to minimize the intra-cluster energy cost by jointly obtaining the optimal sensing durations and thresholds of feature detectors for the proposed voting rule. Likewise, instead of a common fixed sample size test, we developed a weighted sample size test for quantized soft decision fusion to obtain a more EE regime under heterogeneity. We have shown that the combination of proposed CH selection and cooperation schemes gives a superior performance in terms of energy efficiency and robustness against reporting error wall.

Skeletal effects and functional outcome with olpadronate in children with osteogenesis imperfecta: a 2-year randomised placebo-controlled study

NARCIS (Netherlands)

Sakkers, Ralph; Kok, Dieke; Engelbert, Raoul; van Dongen, Alice; Jansen, Maarten; Pruijs, Hans; Verbout, Ab; Schweitzer, Dave; Uiterwaal, Cuno

2004-01-01

Non-randomised studies have suggested beneficial effects of bisphosphonates in osteogenesis imperfecta. We assessed the effects of oral olpadronate in children with this disorder in a randomised double-blind placebo-controlled trial. 34 children recruited from the Dutch national centre for

Effectiveness of educational poster on knowledge of emergency management of dental trauma--part 2: cluster randomised controlled trial for secondary school students.

Science.gov (United States)

Young, Cecilia; Wong, Kin Yau; Cheung, Lim K

2014-01-01

To investigate the effectiveness of educational poster on improving secondary school students' knowledge of emergency management of dental trauma. A cluster randomised controlled trial was conducted. 16 schools with total 671 secondary students who can read Chinese or English were randomised into intervention (poster, 8 schools, 364 students) and control groups (8 schools, 305 students) at the school level. Baseline knowledge of dental trauma was obtained by a questionnaire. Poster containing information of dental trauma management was displayed in a classroom for 2 weeks in each school in the intervention group whereas in the control group there was no display of such posters. Students of both groups completed the same questionnaire after 2 weeks. Two-week display of posters improved the knowledge score by 1.25 (p-value = 0.0407) on average. Educational poster on dental trauma management significantly improved the level of knowledge of secondary school students in Hong Kong. HKClinicalTrial.com HKCTR-1343 ClinicalTrials.gov NCT01809457.

Dynamic clustering scheme based on the coordination of management and control in multi-layer and multi-region intelligent optical network

Science.gov (United States)

Niu, Xiaoliang; Yuan, Fen; Huang, Shanguo; Guo, Bingli; Gu, Wanyi

2011-12-01

A Dynamic clustering scheme based on coordination of management and control is proposed to reduce network congestion rate and improve the blocking performance of hierarchical routing in Multi-layer and Multi-region intelligent optical network. Its implement relies on mobile agent (MA) technology, which has the advantages of efficiency, flexibility, functional and scalability. The paper's major contribution is to adjust dynamically domain when the performance of working network isn't in ideal status. And the incorporation of centralized NMS and distributed MA control technology migrate computing process to control plane node which releases the burden of NMS and improves process efficiently. Experiments are conducted on Multi-layer and multi-region Simulation Platform for Optical Network (MSPON) to assess the performance of the scheme.

A Cluster-Randomised Trial of Staff Education to Improve the Quality of Life of People with Dementia Living in Residential Care: The DIRECT Study

OpenAIRE

Beer, Christopher; Horner, Barbara; Flicker, Leon; Scherer, Samuel; Lautenschlager, Nicola T.; Bretland, Nick; Flett, Penelope; Schaper, Frank; Almeida, Osvaldo P.

2011-01-01

BACKGROUND: The Dementia In Residential care: EduCation intervention Trial (DIRECT) was conducted to determine if delivery of education designed to meet the perceived need of GPs and care staff improves the quality of life of participants with dementia living in residential care. METHODOLOGY/PRINCIPAL FINDINGS: This cluster-randomised controlled trial was conducted in 39 residential aged care facilities in the metropolitan area of Perth, Western Australia. 351 care facility residents aged 65 ...

A community mobilisation intervention to prevent violence against women and reduce HIV/AIDS risk in Kampala, Uganda (the SASA! Study: study protocol for a cluster randomised controlled trial

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Abramsky Tanya

2012-06-01

. Discussion This is one of few cluster randomised trials globally to assess the impact of a gender-focused community mobilisation intervention. The multi-disciplinary research approach will enable us to address questions of intervention impact and mechanisms of action, as well as its feasibility, acceptability and transferability to other contexts. The results will be of importance to researchers, policy makers and those working on the front line to prevent violence against women and HIV. Trial registration ClinicalTrials.Gov NCT00790959

Recruiting faith- and non-faith-based schools, adolescents and parents to a cluster randomised sexual-health trial: experiences, challenges and lessons from the mixed-methods Jack Feasibility Trial.

Science.gov (United States)

Aventin, Áine; Lohan, Maria; Maguire, Lisa; Clarke, Mike

2016-07-29

The move toward evidence-based education has led to increasing numbers of randomised trials in schools. However, the literature on recruitment to non-clinical trials is relatively underdeveloped, when compared to that of clinical trials. Recruitment to school-based randomised trials is, however, challenging, even more so when the focus of the study is a sensitive issue such as sexual health. This article reflects on the challenges of recruiting post-primary schools, adolescent pupils and parents to a cluster randomised feasibility trial of a sexual-health intervention, and the strategies employed to address them. The Jack Trial was funded by the UK National Institute for Health Research. It comprised a feasibility study of an interactive film-based sexual-health intervention entitled If I Were Jack, recruiting over 800 adolescents from eight socio-demographically diverse post-primary schools in Northern Ireland. It aimed to determine the facilitators and barriers to recruitment and retention to a school-based sexual-health trial and identify optimal multi-level strategies for an effectiveness study. As part of an embedded process evaluation, we conducted semi-structured interviews and focus groups with principals, vice-principals, teachers, pupils and parents recruited to the study as well as classroom observations and a parents' survey. With reference to social learning theory, we identified a number of individual-, behavioural- and environmental-level factors that influenced recruitment. Commonly identified facilitators included perceptions of the relevance and potential benefit of the intervention to adolescents, the credibility of the organisation and individuals running the study, support offered by trial staff, and financial incentives. Key barriers were prior commitment to other research, lack of time and resources, and perceptions that the intervention was incompatible with pupil or parent needs or the school ethos. Reflecting on the methodological

The serious mental illness health improvement profile [HIP]: study protocol for a cluster randomised controlled trial

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Swift Louise

2011-07-01

Full Text Available Abstract Background The serious mental illness Health Improvement Profile [HIP] is a brief pragmatic tool, which enables mental health nurses to work together with patients to screen physical health and take evidence-based action when variables are identified to be at risk. Piloting has demonstrated clinical utility and acceptability. Methods/Design A single blind parallel group cluster randomised controlled trial with secondary economic analysis and process observation. Unit of randomisation: mental health nurses [MHNs] working in adult community mental health teams across two NHS Trusts. Subjects: Patients over 18 years with a diagnosis of schizophrenia, schizoaffective or bipolar disorder on the caseload of participating MHNs. Primary objective: To determine the effects of the HIP programme on patients' physical wellbeing assessed by the physical component score of the Medical Outcome Study (MOS 36 Item Short Form Health Survey version 2 [SF-36v2]. Secondary objectives: To determine the effects of the HIP programme on: cost effectiveness, mental wellbeing, cardiovascular risk, physical health care attitudes and knowledge of MHNs and to determine the acceptability of the HIP Programme in the NHS. Consented nurses (and patients will be randomised to receive the HIP Programme or treatment as usual. Outcomes will be measured at baseline and 12 months with a process observation after 12 months to include evaluation of patients' and professionals' experience and observation of any effect on care plans and primary-secondary care interface communication. Outcomes will be analysed on an intention-to-treat (ITT basis. Discussion The results of the trial and process observation will provide information about the effectiveness of the HIP Programme in supporting MHNs to address physical comorbidity in serious mental illness. Given the current unacceptable prevalence of physical comorbidity and mortality in the serious mental illness population, it is

Community engagement and integrated health and polio immunisation campaigns in conflict-affected areas of Pakistan: a cluster randomised controlled trial.

Science.gov (United States)

Habib, Muhammad Atif; Soofi, Sajid; Cousens, Simon; Anwar, Saeed; Haque, Najib Ul; Ahmed, Imran; Ali, Noshad; Tahir, Rehman; Bhutta, Zulfiqar A

2017-06-01

Pakistan faces huge challenges in eradicating polio due to widespread poliovirus transmission and security challenges. Innovative interventions are urgently needed to strengthen community buy-in, to increase the coverage of oral polio vaccine (OPV) and other routine immunisations, and to enhance immunity through the introduction of inactivated polio vaccine (IPV) in combination with OPV. We aimed to evaluate the acceptability and effect on immunisation coverage of an integrated strategy for community engagement and maternal and child health immunisation campaigns in insecure and conflict-affected polio-endemic districts of Pakistan. We did a community-based three-arm cluster randomised trial in healthy children aged 1 month to 5 years that resided within the study sites in three districts of Pakistan at high risk of polio. Clusters were randomly assigned by a computer algorithm using restricted randomisation in blocks of 20 by an external statistician (1:1:1) to receive routine polio programme activities (control, arm A), additional interventions with community outreach and mobilisation using an enhanced communication package and provision of short-term preventive maternal and child health services and routine immunisation (health camps), including OPV (arm B), or all interventions of arm B with additional provision of IPV delivered at the maternal and child health camps (arm C). An independent team conducted surveys at baseline, endline, and after each round of supplementary immunisation activity for acceptability and effect. The primary outcome measures for the study were coverage of OPV, IPV, and routine extended programme on immunisation vaccines and changes in the proportion of unvaccinated and fully vaccinated children. This trial is registered with ClinicalTrials.gov, number NCT01908114. Between June 4, 2013, and May 31, 2014, 387 clusters were randomised (131 to arm A, 127 to arm B, and 129 to arm C). At baseline, 28 760 children younger than 5 years were

Molecular depth profiling of multi-layer systems with cluster ion sources

Energy Technology Data Exchange (ETDEWEB)

Cheng, Juan [Department of Chemistry, Penn State University, University Park, PA 16802 (United States); Winograd, Nicholas [Department of Chemistry, Penn State University, University Park, PA 16802 (United States)]. E-mail: nxw@psu.edu

2006-07-30

Cluster bombardment of molecular films has created new opportunities for SIMS research. To more quantitatively examine the interaction of cluster beams with organic materials, we have developed a reproducible platform consisting of a well-defined sugar film (trehalose) doped with peptides. Molecular depth profiles have been acquired with these systems using C{sub 60} {sup +} bombardment. In this study, we utilize this platform to determine the feasibility of examining buried interfaces for multi-layer systems. Using C{sub 60} {sup +} at 20 keV, several systems have been tested including Al/trehalose/Si, Al/trehalose/Al/Si, Ag/trehalose/Si and ice/trehalose/Si. The results show that there can be interactions between the layers during the bombardment process that prevent a simple interpretation of the depth profile. We find so far that the best results are obtained when the mass of the overlayer atoms is less than or nearly equal to the mass of the atoms in buried molecules. In general, these observations suggest that C{sub 60} {sup +} bombardment can be successfully applied to interface characterization of multi-layer systems if the systems are carefully chosen.

The effectiveness of the Austrian disease management programme for type 2 diabetes: a cluster-randomised controlled trial

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Klima Gert

2010-11-01

Full Text Available Abstract Background Disease management programmes (DMPs are costly and impose additional work load on general practitioners (GPs. Data on their effectiveness are inconclusive. We therefore conducted a cluster-randomised controlled trial to evaluate the effectiveness of the Austrian DMP for diabetes mellitus type 2 on HbA1c and quality of care for adult patients in primary care. Methods All GPs of Salzburg-province were invited to participate. After cluster-randomisation by district, all patients with diabetes type 2 were recruited consecutively from 7-11/2007. The DMP, consisting mainly of physician and patient education, standardised documentation and agreement on therapeutic goals, was implemented in the intervention group while the control group received usual care. We aimed to show superiority of the intervention regarding metabolic control and process quality. The primary outcome measure was a change in HbA1c after one year. Secondary outcomes were days in the hospital, blood pressure, lipids, body mass index (BMI, enrolment in patient education and regular guideline-adherent examination. Blinding was not possible. Results 92 physicians recruited 1489 patients (649 intervention, 840 control. After 401 ± 47 days, 590 intervention-patients and 754 controls had complete data. In the intention to treat analysis (ITT of all 1489 patients, HbA1c decreased 0.41% in the intervention group and 0.28% in controls. The difference of -0.13% (95% CI -0.24; -0.02 was significant at p = 0.026. Significance was lost in mixed models adjusted for baseline value and cluster-effects (adjusted mean difference -0.03 (95% CI -0.15; 0.09, p = 0.607. Of the secondary outcome measures, BMI and cholesterol were significantly reduced in the intervention group compared to controls in ITT after adjustments (-0.53 kg/m²; 95% CI -1.03;-0.02; p = 0.014 and -0.10 mmol/l; 95% CI -0.21; -0.003; p = 0.043. Additionally, more patients received patient education (49.5% vs. 20

ZOOM or Non-ZOOM? Assessing Spinal Cord Diffusion Tensor Imaging Protocols for Multi-Centre Studies.

Directory of Open Access Journals (Sweden)

Rebecca S Samson

Full Text Available The purpose of this study was to develop and evaluate two spinal cord (SC diffusion tensor imaging (DTI protocols, implemented at multiple sites (using scanners from two different manufacturers, one available on any clinical scanner, and one using more advanced options currently available in the research setting, and to use an automated processing method for unbiased quantification. DTI parameters are sensitive to changes in the diseased SC. However, imaging the cord can be technically challenging due to various factors including its small size, patient-related and physiological motion, and field inhomogeneities. Rapid acquisition sequences such as Echo Planar Imaging (EPI are desirable but may suffer from image distortions. We present a multi-centre comparison of two acquisition protocols implemented on scanners from two different vendors (Siemens and Philips, one using a reduced field-of-view (rFOV EPI sequence, and one only using options available on standard clinical scanners such as outer volume suppression (OVS. Automatic analysis was performed with the Spinal Cord Toolbox for unbiased and reproducible quantification of DTI metrics in the white matter. Images acquired using the rFOV sequence appear less distorted than those acquired using OVS alone. SC DTI parameter values obtained using both sequences at all sites were consistent with previous measurements made at 3T. For the same scanner manufacturer, DTI parameter inter-site SDs were smaller for the rFOV sequence compared to the OVS sequence. The higher inter-site reproducibility (for the same manufacturer and acquisition details, i.e. ZOOM data acquired at the two Philips sites of rFOV compared to the OVS sequence supports the idea that making research options such as rFOV more widely available would improve accuracy of measurements obtained in multi-centre clinical trials. Future multi-centre studies should also aim to match the rFOV technique and signal-to-noise ratios in all

Oxytocin via Uniject (a prefilled single-use injection) versus oral misoprostol for prevention of postpartum haemorrhage at the community level: a cluster-randomised controlled trial

OpenAIRE

Ayisha Diop, MPH; Bocar Daff, MD; Maimouna Sow, MA; Jennifer Blum, MPH; Mamadou Diagne, PhD; Nancy L Sloan, DrPH; Beverly Winikoff, MD

2016-01-01

Background: Access to injectable uterotonics for management of postpartum haemorrhage remains limited in Senegal outside health facilities, and misoprostol and oxytocin delivered via Uniject have been deemed viable alternatives in community settings. We aimed to compare the efficacy of these drugs when delivered by auxiliary midwives at maternity huts. Methods: We did an unmasked cluster-randomised controlled trial at maternity huts in three districts in Senegal. Maternity huts with auxili...

Effects of PREPARE, a Multi-component, School-Based HIV and Intimate Partner Violence (IPV) Prevention Programme on Adolescent Sexual Risk Behaviour and IPV: Cluster Randomised Controlled Trial.

Science.gov (United States)

Mathews, Catherine; Eggers, Sander M; Townsend, Loraine; Aarø, Leif E; de Vries, Petrus J; Mason-Jones, Amanda J; De Koker, Petra; McClinton Appollis, Tracy; Mtshizana, Yolisa; Koech, Joy; Wubs, Annegreet; De Vries, Hein

2016-09-01

Young South Africans, especially women, are at high risk of HIV. We evaluated the effects of PREPARE, a multi-component, school-based HIV prevention intervention to delay sexual debut, increase condom use and decrease intimate partner violence (IPV) among young adolescents. We conducted a cluster RCT among Grade eights in 42 high schools. The intervention comprised education sessions, a school health service and a school sexual violence prevention programme. Participants completed questionnaires at baseline, 6 and 12 months. Regression was undertaken to provide ORs or coefficients adjusted for clustering. Of 6244 sampled adolescents, 55.3 % participated. At 12 months there were no differences between intervention and control arms in sexual risk behaviours. Participants in the intervention arm were less likely to report IPV victimisation (35.1 vs. 40.9 %; OR 0.77, 95 % CI 0.61-0.99; t(40) = 2.14) suggesting the intervention shaped intimate partnerships into safer ones, potentially lowering the risk for HIV.

Timing of birth for women with a twin pregnancy at term: a randomised controlled trial

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Haslam Ross R

2010-10-01

Full Text Available Abstract Background There is a well recognized risk of complications for both women and infants of a twin pregnancy, increasing beyond 37 weeks gestation. Preterm birth prior to 37 weeks gestation is a recognized complication of a twin pregnancy, however, up to 50% of twins will be born after this time. The aims of this randomised trial are to assess whether elective birth at 37 weeks gestation compared with standard care in women with a twin pregnancy affects the risk of perinatal death, and serious infant complications. Methods/Design Design: Multicentred randomised trial. Inclusion Criteria: women with a twin pregnancy at 366 weeks or more without contraindication to continuation of pregnancy. Trial Entry & Randomisation: Following written informed consent, eligible women will be randomised from 36+6 weeks gestation. The randomisation schedule uses balanced variable blocks, with stratification for centre of birth and planned mode of birth. Women will be randomised to either elective birth or standard care. Treatment Schedules: Women allocated to the elective birth group will be planned for elective birth from 37 weeks gestation. Where the plan is for vaginal birth, this will involve induction of labour. Where the plan is for caesarean birth, this will involve elective caesarean section. For women allocated to standard care, birth will be planned for 38 weeks gestation or later. Where the plan is for vaginal birth, this will involve either awaiting the spontaneous onset of labour, or induction of labour if required. Where the plan is for caesarean birth, this will involve elective caesarean section (after 38 and as close to 39 weeks as possible. Primary Study Outcome: A composite of perinatal mortality or serious neonatal morbidity. Sample Size: 460 women with a twin pregnancy to show a reduction in the composite outcome from 16.3% to 6.7% with adjustment for the clustering of twin infants within mothers (p = 0.05, 80% power. Discussion This

Large-Scale Multi-Dimensional Document Clustering on GPU Clusters

Energy Technology Data Exchange (ETDEWEB)

Cui, Xiaohui [ORNL; Mueller, Frank [North Carolina State University; Zhang, Yongpeng [ORNL; Potok, Thomas E [ORNL

2010-01-01

Document clustering plays an important role in data mining systems. Recently, a flocking-based document clustering algorithm has been proposed to solve the problem through simulation resembling the flocking behavior of birds in nature. This method is superior to other clustering algorithms, including k-means, in the sense that the outcome is not sensitive to the initial state. One limitation of this approach is that the algorithmic complexity is inherently quadratic in the number of documents. As a result, execution time becomes a bottleneck with large number of documents. In this paper, we assess the benefits of exploiting the computational power of Beowulf-like clusters equipped with contemporary Graphics Processing Units (GPUs) as a means to significantly reduce the runtime of flocking-based document clustering. Our framework scales up to over one million documents processed simultaneously in a sixteennode GPU cluster. Results are also compared to a four-node cluster with higher-end GPUs. On these clusters, we observe 30X-50X speedups, which demonstrates the potential of GPU clusters to efficiently solve massive data mining problems. Such speedups combined with the scalability potential and accelerator-based parallelization are unique in the domain of document-based data mining, to the best of our knowledge.

Are specialist outreach clinics for orthodontic consultation effective? A randomised controlled trial

OpenAIRE

Mandall, Nicola; O'Brien, K.

2001-01-01

Objective To develop outreach clinics for orthodontic consultation and evaluate their costs and effectiveness. Design Single centre randomised controlled trial with random allocation of referred patients to outreach or main base consultation appointments. Setting One hospital orthodontic department and three community health centre clinics in Greater Manchester. Subjects 324 patients who were referred for orthodontic treatment. Main outcome measures The outcome of consultation, the cost and d...

A multi-faceted workplace intervention targeting low back pain was effective for physical work demands and maladaptive pain behaviours, but not for work ability and sickness absence: Stepped wedge cluster randomised trial.

Science.gov (United States)

Rasmussen, Charlotte Diana Nørregaard; Holtermann, Andreas; Jørgensen, Marie Birk; Ørberg, Anders; Mortensen, Ole Steen; Søgaard, Karen

2016-08-01

The aims of this study were to test whether a multi-faceted intervention effective for low back pain was effective for physical capacity, work demands, maladaptive pain behaviours, work ability and sickness absence due to low back pain. A stepped wedge cluster randomised, controlled trial with 594 nurses' aides was conducted. The intervention lasted 12 weeks and consisted of physical training (12 sessions), cognitive behavioural training (two sessions) and participatory ergonomics (five sessions). Occupational lifting, fear avoidance, physical exertion, muscle strength, support from management, work ability and sickness absence due to low back pain were measured every 3 months. Before and after the intervention we measured physical capacity, kinesiophobia and need for recovery. Linear mixed models adjusted for baseline values of the outcome were used to estimate the effect. Significant reduction in occupational lifting (-0.35 (95% confidence interval -0.61 to -0.08)), and improvement in two measures of fear avoidance ((-0.75 (95% confidence interval -1.05 to -0.45) and -0.45 (95% confidence interval -0.80 to -0.11)) were found for the intervention group compared to the control. There were no significant effects on physical exertion, muscle strength, support from management, work ability or sickness absence due to low back pain. After the intervention, significant increased physical capacity and improvements in kinesiophobia were found, but no change in need for recovery. CONCLUSIONS THE INTERVENTION WAS SIGNIFICANTLY EFFECTIVE FOR PHYSICAL WORK DEMANDS AND MALADAPTIVE PAIN BEHAVIOURS, BUT NOT FOR WORK ABILITY AND SICKNESS ABSENCE DUE TO LOW BACK PAIN TO IMPROVE WORK ABILITY OR REDUCE SICKNESS ABSENCE DUE TO LOW BACK PAIN MORE SPECIFIC INTERVENTIONS SHOULD PROBABLY BE DEVELOPED. © 2016 the Nordic Societies of Public Health.

Effectiveness and cost-effectiveness of body psychotherapy in the treatment of negative symptoms of schizophrenia – a multi-centre randomised controlled trial

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Priebe Stefan

2013-01-01

Full Text Available Abstract Background Negative symptoms of schizophrenia are frequently associated with poor long term outcomes. Established interventions have little, if any, positive effects on negative symptoms. Arts Therapies such as Body Psychotherapy (BPT have been suggested to reduce negative symptoms, but the existing evidence is limited. In a small exploratory trial a manualised form of group BPT led to significantly lower negative symptom levels both at the end of treatment and at 4 months follow-up as compared to supportive counseling. We designed a large multi-site trial to assess the effectiveness of a manualised BPT intervention in reducing negative symptoms, compared to an active control. Methods/Design In a randomised controlled trial, 256 schizophrenic outpatients with negative symptoms will be randomly allocated either to BPT or Pilates groups. In both conditions, patients will be offered two 90 minutes sessions per week in groups of about 8 patients over a period of 10 weeks. Outcomes are assessed at the end of treatment and at six months follow-up. The primary outcome is severity of negative symptoms, as measured by the Positive and Negative Symptom Scale (PANSS, whilst a range of secondary outcome measures include general psychopathology, social contacts, and quality of life. We will also assess the cost-effectiveness of the intervention. Discussion The study aims to evaluate the effectiveness of a promising form of group therapy which may help alleviate negative symptoms that are associated with unfavourable long-term outcomes and have so far been difficult to treat. If the trial is successful, it will add a new and effective option in the treatment of negative symptoms. Group BPT is manualised, might be attractive to many patients because of its unusual approach, and could potentially be rolled out to services at relatively little additional cost. Trial registration Current Controlled Trials ISRCTN84216587

Community mobilisation with women's groups facilitated by Accredited Social Health Activists (ASHAs to improve maternal and newborn health in underserved areas of Jharkhand and Orissa: study protocol for a cluster-randomised controlled trial

Directory of Open Access Journals (Sweden)

Sinha Rajesh

2011-07-01

Full Text Available Abstract Background Around a quarter of the world's neonatal and maternal deaths occur in India. Morbidity and mortality are highest in rural areas and among the poorest wealth quintiles. Few interventions to improve maternal and newborn health outcomes with government-mandated community health workers have been rigorously evaluated at scale in this setting. The study aims to assess the impact of a community mobilisation intervention with women's groups facilitated by ASHAs to improve maternal and newborn health outcomes among rural tribal communities of Jharkhand and Orissa. Methods/design The study is a cluster-randomised controlled trial and will be implemented in five districts, three in Jharkhand and two in Orissa. The unit of randomisation is a rural cluster of approximately 5000 population. We identified villages within rural, tribal areas of five districts, approached them for participation in the study and enrolled them into 30 clusters, with approximately 10 ASHAs per cluster. Within each district, 6 clusters were randomly allocated to receive the community intervention or to the control group, resulting in 15 intervention and 15 control clusters. Randomisation was carried out in the presence of local stakeholders who selected the cluster numbers and allocated them to intervention or control using a pre-generated random number sequence. The intervention is a participatory learning and action cycle where ASHAs support community women's groups through a four-phase process in which they identify and prioritise local maternal and newborn health problems, implement strategies to address these and evaluate the result. The cycle is designed to fit with the ASHAs' mandate to mobilise communities for health and to complement their other tasks, including increasing institutional delivery rates and providing home visits to mothers and newborns. The trial's primary endpoint is neonatal mortality during 24 months of intervention. Additional

Adding a post-training FIFA 11+ exercise program to the pre-training FIFA 11+ injury prevention program reduces injury rates among male amateur soccer players: a cluster-randomised trial

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Wesam Saleh A Al Attar

2017-10-01

Trial registration: ACTRN12615001206516. [Al Attar WSA, Soomro N, Pappas E, Sinclair PJ, Sanders RH (2017 Adding a post-training FIFA 11+ exercise program to the pre-training FIFA 11+ injury prevention program reduces injury rates among male amateur soccer players: a cluster-randomised trial. Journal of Physiotherapy 63: 235–242

Clustering of samples and elements based on multi-variable chemical data

International Nuclear Information System (INIS)

Op de Beeck, J.

1984-01-01

Clustering and classification are defined in the context of multivariable chemical analysis data. Classical multi-variate techniques, commonly used to interpret such data, are shown to be based on probabilistic and geometrical principles which are not justified for analytical data, since in that case one assumes or expects a system of more or less systematically related objects (samples) as defined by measurements on more or less systematically interdependent variables (elements). For the specific analytical problem of data set concerning a large number of trace elements determined in a large number of samples, a deterministic cluster analysis can be used to develop the underlying classification structure. Three main steps can be distinguished: diagnostic evaluation and preprocessing of the raw input data; computation of a symmetric matrix with pairwise standardized dissimilarity values between all possible pairs of samples and/or elements; and ultrametric clustering strategy to produce the final classification as a dendrogram. The software packages designed to perform these tasks are discussed and final results are given. Conclusions are formulated concerning the dangers of using multivariate, clustering and classification software packages as a black-box

Membership determination of open clusters based on a spectral clustering method

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Gao, Xin-Hua

2018-06-01

We present a spectral clustering (SC) method aimed at segregating reliable members of open clusters in multi-dimensional space. The SC method is a non-parametric clustering technique that performs cluster division using eigenvectors of the similarity matrix; no prior knowledge of the clusters is required. This method is more flexible in dealing with multi-dimensional data compared to other methods of membership determination. We use this method to segregate the cluster members of five open clusters (Hyades, Coma Ber, Pleiades, Praesepe, and NGC 188) in five-dimensional space; fairly clean cluster members are obtained. We find that the SC method can capture a small number of cluster members (weak signal) from a large number of field stars (heavy noise). Based on these cluster members, we compute the mean proper motions and distances for the Hyades, Coma Ber, Pleiades, and Praesepe clusters, and our results are in general quite consistent with the results derived by other authors. The test results indicate that the SC method is highly suitable for segregating cluster members of open clusters based on high-precision multi-dimensional astrometric data such as Gaia data.

clusterMaker: a multi-algorithm clustering plugin for Cytoscape

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Morris John H

2011-11-01

Full Text Available Abstract Background In the post-genomic era, the rapid increase in high-throughput data calls for computational tools capable of integrating data of diverse types and facilitating recognition of biologically meaningful patterns within them. For example, protein-protein interaction data sets have been clustered to identify stable complexes, but scientists lack easily accessible tools to facilitate combined analyses of multiple data sets from different types of experiments. Here we present clusterMaker, a Cytoscape plugin that implements several clustering algorithms and provides network, dendrogram, and heat map views of the results. The Cytoscape network is linked to all of the other views, so that a selection in one is immediately reflected in the others. clusterMaker is the first Cytoscape plugin to implement such a wide variety of clustering algorithms and visualizations, including the only implementations of hierarchical clustering, dendrogram plus heat map visualization (tree view, k-means, k-medoid, SCPS, AutoSOME, and native (Java MCL. Results Results are presented in the form of three scenarios of use: analysis of protein expression data using a recently published mouse interactome and a mouse microarray data set of nearly one hundred diverse cell/tissue types; the identification of protein complexes in the yeast Saccharomyces cerevisiae; and the cluster analysis of the vicinal oxygen chelate (VOC enzyme superfamily. For scenario one, we explore functionally enriched mouse interactomes specific to particular cellular phenotypes and apply fuzzy clustering. For scenario two, we explore the prefoldin complex in detail using both physical and genetic interaction clusters. For scenario three, we explore the possible annotation of a protein as a methylmalonyl-CoA epimerase within the VOC superfamily. Cytoscape session files for all three scenarios are provided in the Additional Files section. Conclusions The Cytoscape plugin cluster

Subaru Weak-Lensing Survey II: Multi-Object Spectroscopy and Cluster Masses

Science.gov (United States)

Hamana, Takashi; Miyazaki, Satoshi; Kashikawa, Nobunari; Ellis, Richard S.; Massey, Richard J.; Refregier, Alexandre; Taylor, James E.

2009-08-01

We present the first results of a multi-object spectroscopic campaign to follow up cluster candidates located via weak lensing. Our main goals are to search for spatial concentrations of galaxies that are plausible optical counterparts of the weak-lensing signals, and to determine the cluster redshifts from those of member galaxies. Around each of 36 targeted cluster candidates, we obtained 15-32 galaxy redshifts. For 28 of these targets, we confirmed a secure cluster identification, with more than five spectroscopic galaxies within a velocity of ±3000km s-1. This includes three cases where two clusters at different redshifts are projected along the same line-of-sight. In 6 of the 8 unconfirmed targets, we found multiple small galaxy concentrations at different redshifts, each containing at least three spectroscopic galaxies. The weak-lensing signal around those systems was thus probably created by the projection of groups or small clusters along the same line-of-sight. In both of the remaining two targets, a single small galaxy concentration was found. In some candidate super-cluster systems, we found additional evidence of filaments connecting the main density peak to an additional nearby structure. For a subsample of our most cleanly measured clusters, we investigated the statistical relation between their weak-lensing mass (MNFW, σSIS) and the velocity dispersion of their member galaxies (σv), comparing our sample with optically and X-ray selected samples from the literature. Our lensing-selected clusters are consistent with σv = σSIS, with a similar scatter to that of optically and X-ray selected clusters. We also derived an empirical relation between the cluster mass and the galaxy velocity dispersion, M200E(z) = 11.0 × 1014 × (σv/1000km s-1)3.0 h-1 Modot, which is in reasonable agreement with predictions of N-body simulations in the Λ CDM cosmology.

Study protocol: a cluster randomised controlled trial of a school based fruit and vegetable intervention – Project Tomato

Science.gov (United States)

Kitchen, Meaghan S; Ransley, Joan K; Greenwood, Darren C; Clarke, Graham P; Conner, Mark T; Jupp, Jennifer; Cade, Janet E

2009-01-01

Background The School Fruit and Vegetable Scheme (SFVS) is an important public health intervention. The aim of this scheme is to provide a free piece of fruit and/or vegetable every day for children in Reception to Year 2. When children are no longer eligible for the scheme (from Year 3) their overall fruit and vegetable consumption decreases back to baseline levels. This proposed study aims to design a flexible multi-component intervention for schools to support the maintenance of fruit and vegetable consumption for Year 3 children who are no longer eligible for the scheme. Method This study is a cluster randomised controlled trial of Year 2 classes from 54 primary schools across England. The schools will be randomly allocated into two groups to receive either an active intervention called Project Tomato, to support maintenance of fruit intake in Year 3 children, or a less active intervention (control group), consisting of a 5 A DAY booklet. Children's diets will be analysed using the Child And Diet Evaluation Tool (CADET), and height and weight measurements collected, at baseline (Year 2) and 18 month follow-up (Year 4). The primary outcome will be the ability of the intervention (Project Tomato) to maintain consumption of fruit and vegetable portions compared to the control group. Discussion A positive result will identify how fruit and vegetable consumption can be maintained in young children, and will be useful for policies supporting the SFVS. A negative result would be used to inform the research agenda and contribute to redefining future strategies for increasing children's fruit and vegetable consumption. Trial registration Medical Research Council Registry code G0501297 PMID:19531246

Study protocol: a cluster randomised controlled trial of a school based fruit and vegetable intervention – Project Tomato

Directory of Open Access Journals (Sweden)

Conner Mark T

2009-06-01

Full Text Available Abstract Background The School Fruit and Vegetable Scheme (SFVS is an important public health intervention. The aim of this scheme is to provide a free piece of fruit and/or vegetable every day for children in Reception to Year 2. When children are no longer eligible for the scheme (from Year 3 their overall fruit and vegetable consumption decreases back to baseline levels. This proposed study aims to design a flexible multi-component intervention for schools to support the maintenance of fruit and vegetable consumption for Year 3 children who are no longer eligible for the scheme. Method This study is a cluster randomised controlled trial of Year 2 classes from 54 primary schools across England. The schools will be randomly allocated into two groups to receive either an active intervention called Project Tomato, to support maintenance of fruit intake in Year 3 children, or a less active intervention (control group, consisting of a 5 A DAY booklet. Children's diets will be analysed using the Child And Diet Evaluation Tool (CADET, and height and weight measurements collected, at baseline (Year 2 and 18 month follow-up (Year 4. The primary outcome will be the ability of the intervention (Project Tomato to maintain consumption of fruit and vegetable portions compared to the control group. Discussion A positive result will identify how fruit and vegetable consumption can be maintained in young children, and will be useful for policies supporting the SFVS. A negative result would be used to inform the research agenda and contribute to redefining future strategies for increasing children's fruit and vegetable consumption. Trial registration Medical Research Council Registry code G0501297

Update to a protocol for a feasibility cluster randomised controlled trial of a peer-led school-based intervention to increase the physical activity of adolescent girls (PLAN-A).

Science.gov (United States)

Sebire, Simon J; Edwards, Mark J; Campbell, Rona; Jago, Russell; Kipping, Ruth; Banfield, Kathryn; Kadir, Bryar; Garfield, Kirsty; Lyons, Ronan A; Blair, Peter S; Hollingworth, William

2016-01-01

Physical activity levels are low amongst adolescent girls, and this population faces specific barriers to being active. Peer influences on health behaviours are important in adolescence, and peer-led interventions might hold promise to change behaviour. This paper describes the protocol for a feasibility cluster randomised controlled trial of Peer-Led physical Activity iNtervention for Adolescent girls (PLAN-A), a peer-led intervention aimed at increasing adolescent girls' physical activity levels. In addition, this paper describes an update that has been made to the protocol for the PLAN-A feasibility cluster randomised controlled trial. A two-arm cluster randomised feasibility trial will be conducted in six secondary schools (intervention n  = 4; control n  = 2) with year 8 (12-13 years old) girls. The intervention will operate at a year group level and consist of year 8 girls nominating influential peers within their year group to become peer supporters. Approximately 15% of the cohort will receive 3 days of training about physical activity and interpersonal communication skills. Peer supporters will then informally diffuse messages about physical activity amongst their friends for 10 weeks. Data will be collected at baseline (time 0 (T0)), immediately after the intervention (time 1 (T1)) and 12 months after baseline measures (time 2 (T2)). In this feasibility trial, the primary interest is in the recruitment of schools and participants (both year 8 girls and peer supporters), delivery and receipt of the intervention, data provision rates and identifying the cost categories for future economic analysis. Physical activity will be assessed using 7-day accelerometry, with the likely primary outcome in a fully powered trial being daily minutes of moderate-to-vigorous physical activity. Participants will also complete psychosocial questionnaires at each time point: assessing motivation, self-esteem and peer physical activity norms. Data analysis will be

Mobile phones as a health communication tool to improve skilled attendance at delivery in Zanzibar: a cluster-randomised controlled trial.

Science.gov (United States)

Lund, S; Hemed, M; Nielsen, B B; Said, A; Said, K; Makungu, M H; Rasch, V

2012-09-01

To examine the association between a mobile phone intervention and skilled delivery attendance in a resource-limited setting. Pragmatic cluster-randomised controlled trial with primary healthcare facilities as the unit of randomisation. Primary healthcare facilities in Zanzibar. Two thousand, five hundred and fifty pregnant women (1311 interventions and 1239 controls) who attended antenatal care at one of the selected primary healthcare facilities were included at their first antenatal care visit and followed until 42 days after delivery. All pregnant women were eligible for study participation. Twenty-four primary healthcare facilities in six districts in Zanzibar were allocated by simple randomisation to either mobile phone intervention (n = 12) or standard care (n = 12). The intervention consisted of a short messaging service (SMS) and mobile phone voucher component. Skilled delivery attendance. The mobile phone intervention was associated with an increase in skilled delivery attendance: 60% of the women in the intervention group versus 47% in the control group delivered with skilled attendance. The intervention produced a significant increase in skilled delivery attendance amongst urban women (odds ratio, 5.73; 95% confidence interval, 1.51-21.81), but did not reach rural women. The mobile phone intervention significantly increased skilled delivery attendance amongst women of urban residence. Mobile phone solutions may contribute to the saving of lives of women and their newborns and the achievement of Millennium Development Goals 4 and 5, and should be considered by maternal and child health policy makers in developing countries. © 2012 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2012 RCOG.

Effects of non-invasive vagus nerve stimulation on attack frequency over time and expanded response rates in patients with chronic cluster headache: a post hoc analysis of the randomised, controlled PREVA study.

Science.gov (United States)

Gaul, Charly; Magis, Delphine; Liebler, Eric; Straube, Andreas

2017-12-01

In the PREVention and Acute treatment of chronic cluster headache (PREVA) study, attack frequency reductions from baseline were significantly more pronounced with non-invasive vagus nerve stimulation plus standard of care (nVNS + SoC) than with SoC alone. Given the intensely painful and frequent nature of chronic cluster headache attacks, additional patient-centric outcomes, including the time to and level of therapeutic response, were evaluated in a post hoc analysis of the PREVA study. After a 2-week baseline phase, 97 patients with chronic cluster headache entered a 4-week randomised phase to receive nVNS + SoC (n = 48) or SoC alone (n = 49). All 92 patients who continued into a 4-week extension phase received nVNS + SoC. Compared with SoC alone, nVNS + SoC led to a significantly lower mean weekly attack frequency by week 2 of the randomised phase; the attack frequency remained significantly lower in the nVNS + SoC group through week 3 of the extension phase (P cluster headache attack frequency within 2 weeks after its addition to SoC and was associated with significantly higher ≥25%, ≥50%, and ≥75% response rates than SoC alone. The rapid decrease in weekly attack frequency justifies a 4-week trial period to identify responders to nVNS, with a high degree of confidence, among patients with chronic cluster headache.

A cluster-randomised, controlled trial to assess the impact of a workplace osteoporosis prevention intervention on the dietary and physical activity behaviours of working women: study protocol.

Science.gov (United States)

Tan, Ai May; Lamontagne, Anthony D; Sarmugam, Rani; Howard, Peter

2013-04-29

Osteoporosis is a debilitating disease and its risk can be reduced through adequate calcium consumption and physical activity. This protocol paper describes a workplace-based intervention targeting behaviour change in premenopausal women working in sedentary occupations. A cluster-randomised design was used, comparing the efficacy of a tailored intervention to standard care. Workplaces were the clusters and units of randomisation and intervention. Sample size calculations incorporated the cluster design. Final number of clusters was determined to be 16, based on a cluster size of 20 and calcium intake parameters (effect size 250 mg, ICC 0.5 and standard deviation 290 mg) as it required the highest number of clusters.Sixteen workplaces were recruited from a pool of 97 workplaces and randomly assigned to intervention and control arms (eight in each). Women meeting specified inclusion criteria were then recruited to participate. Workplaces in the intervention arm received three participatory workshops and organisation wide educational activities. Workplaces in the control/standard care arm received print resources. Intervention workshops were guided by self-efficacy theory and included participatory activities such as goal setting, problem solving, local food sampling, exercise trials, group discussion and behaviour feedback.Outcomes measures were calcium intake (milligrams/day) and physical activity level (duration: minutes/week), measured at baseline, four weeks and six months post intervention. This study addresses the current lack of evidence for behaviour change interventions focussing on osteoporosis prevention. It addresses missed opportunities of using workplaces as a platform to target high-risk individuals with sedentary occupations. The intervention was designed to modify behaviour levels to bring about risk reduction. It is the first to address dietary and physical activity components each with unique intervention strategies in the context of osteoporosis

Menstrual cups and sanitary pads to reduce school attrition, and sexually transmitted and reproductive tract infections: a cluster randomised controlled feasibility study in rural Western Kenya

OpenAIRE

Phillips-Howard, Penelope; Nyothach, Elizabeth; terKuile, Feiko; Omoto, Jackton; Wang, Duolao; Zeh, Clement; Onyango, Clayton; Mason, Linda; Alexander, Kelly T; Odhiambo, Frank; Eleveld, Alie; Mohammed, Aisha; vanEijk, Anna; Tudor Edwards, Rhiannon; Vulule, John

2016-01-01

Objectives Conduct a feasibility study on the effect of menstrual hygiene on schoolgirls' school and health (reproductive/sexual) outcomes. Design 3-arm single-site open cluster randomised controlled pilot study. Setting 30 primary schools in rural western Kenya, within a Health and Demographic Surveillance System. Participants Primary schoolgirls 14?16?years, experienced 3 menses, no precluding disability, and resident in the study area. Interventions 1 insertable menstrual cup, or monthly s...

Cervical cancer screening in women referred to healthcare centres in Tabriz, Iran.

Science.gov (United States)

Farshbaf-Khalili, Azizeh; Salehi-Pourmehr, Hanieh; Shahnazi, Mahnaz; Yaghoubi, Sina; Gahremani-Nasab, Parvaneh

2015-01-01

Cervical cancer is the second most common cancer among Iranian women and among the few cancers that could be easily diagnosed in the pre-malignant stage. We aimed to assess the status of cervical cancer screening in women referred to health care centres in Tabriz, northwest Iran. This descriptive-analytical study was done on 441 women referred to health care centres of Tabriz, northwest Iran. The centres were selected using the multi-stage cluster sampling method. The participants were selected from the active records of those centres. A questionnaire regarding the socio-demographic characteristics and cervical cancer screening and reasons for referring or not referring for screening was completed by the participants A P marriage or having sexual intercourse at a young age, history of obvious cervical infection, cautery, cryotherapy or repeated curettage), age and type of family planning] in screening was controlled. Suitable and continuous educational programmes especially for high risk women should be implemented through the health care services. Preparing educational brochures and pamphlets and providing adequate training on the necessity of early referral and marriage counseling could also be effective in improving woman's awareness and performance.

A multi-dimensional framework to assist in the design of successful shared services centres

Directory of Open Access Journals (Sweden)

Mark Borman

2012-04-01

Full Text Available Organisations are increasingly looking to realise the benefits of shared services yet there is little guidance available as to the best way to proceed. A multi-dimensional framework is presented that considers the service provided, the design of the shared services centre and the organisational context it sits within. Case studies are then used to determine what specific attributes from each dimension are associated with success and how they should be aligned. It is concluded that there appears to be a single, broadly standard pattern of attributes for successful Shared Services Centres (SSCs across the proposed dimensions of Activity, Environment, History, Resources, Strategy, Structure, Management, Technology and Individual Skills. It should also be noted though that some deviation from the identified standard along some dimensions is possible without adverse effect – ie that the alignment identified appears to be relatively soft.

Effects and meanings of a person-centred and health-promoting intervention in home care services - a study protocol of a non-randomised controlled trial.

Science.gov (United States)

Bölenius, Karin; Lämås, Kristina; Sandman, Per-Olof; Edvardsson, David

2017-02-16

The literature indicates that current home care service are largely task oriented with limited focus on the involvement of the older people themselves, and studies show that lack of involvement might reduce older people's quality of life. Person-centred care has been shown to improve the satisfaction with care and quality of life in older people cared for in hospitals and nursing homes, with limited published evidence about the effects and meanings of person-centred interventions in home care services for older people. This study protocol outlines a study aiming to evaluate such effects and meanings of a person-centred and health-promoting intervention in home aged care services. The study will take the form of a non-randomised controlled trial with a before/after approach. It will include 270 older people >65 years receiving home care services, 270 relatives and 65 staff, as well as a matched control group of equal size. All participants will be recruited from a municipality in northern Sweden. The intervention is based on the theoretical concepts of person-centredness and health-promotion, and builds on the four pedagogical phases of: theory apprehension, experimental learning, operationalization, and clinical supervision. Outcome assessments will focus on: a) health and quality of life (primary outcomes), thriving and satisfaction with care for older people; b) caregiver strain, informal caregiving engagement and relatives' satisfaction with care: c) job satisfaction and stress of conscience among care staff (secondary outcomes). Evaluation will be conducted by means of self-reported questionnaires and qualitative research interviews. Person-centred home care services have the potential to improve the recurrently reported sub-standard experiences of home care services, and the results can point the way to establishing a more person-centred and health-promoting model for home care services for older people. NCT02846246 .

Audiovisual biofeedback breathing guidance for lung cancer patients receiving radiotherapy: a multi-institutional phase II randomised clinical trial.

Science.gov (United States)

Pollock, Sean; O'Brien, Ricky; Makhija, Kuldeep; Hegi-Johnson, Fiona; Ludbrook, Jane; Rezo, Angela; Tse, Regina; Eade, Thomas; Yeghiaian-Alvandi, Roland; Gebski, Val; Keall, Paul J

2015-07-18

There is a clear link between irregular breathing and errors in medical imaging and radiation treatment. The audiovisual biofeedback system is an advanced form of respiratory guidance that has previously demonstrated to facilitate regular patient breathing. The clinical benefits of audiovisual biofeedback will be investigated in an upcoming multi-institutional, randomised, and stratified clinical trial recruiting a total of 75 lung cancer patients undergoing radiation therapy. To comprehensively perform a clinical evaluation of the audiovisual biofeedback system, a multi-institutional study will be performed. Our methodological framework will be based on the widely used Technology Acceptance Model, which gives qualitative scales for two specific variables, perceived usefulness and perceived ease of use, which are fundamental determinants for user acceptance. A total of 75 lung cancer patients will be recruited across seven radiation oncology departments across Australia. Patients will be randomised in a 2:1 ratio, with 2/3 of the patients being recruited into the intervention arm and 1/3 in the control arm. 2:1 randomisation is appropriate as within the interventional arm there is a screening procedure where only patients whose breathing is more regular with audiovisual biofeedback will continue to use this system for their imaging and treatment procedures. Patients within the intervention arm whose free breathing is more regular than audiovisual biofeedback in the screen procedure will remain in the intervention arm of the study but their imaging and treatment procedures will be performed without audiovisual biofeedback. Patients will also be stratified by treating institution and for treatment intent (palliative vs. radical) to ensure similar balance in the arms across the sites. Patients and hospital staff operating the audiovisual biofeedback system will complete questionnaires to assess their experience with audiovisual biofeedback. The objectives of this

Audiovisual biofeedback breathing guidance for lung cancer patients receiving radiotherapy: a multi-institutional phase II randomised clinical trial

International Nuclear Information System (INIS)

Pollock, Sean; O’Brien, Ricky; Makhija, Kuldeep; Hegi-Johnson, Fiona; Ludbrook, Jane; Rezo, Angela; Tse, Regina; Eade, Thomas; Yeghiaian-Alvandi, Roland; Gebski, Val; Keall, Paul J

2015-01-01

There is a clear link between irregular breathing and errors in medical imaging and radiation treatment. The audiovisual biofeedback system is an advanced form of respiratory guidance that has previously demonstrated to facilitate regular patient breathing. The clinical benefits of audiovisual biofeedback will be investigated in an upcoming multi-institutional, randomised, and stratified clinical trial recruiting a total of 75 lung cancer patients undergoing radiation therapy. To comprehensively perform a clinical evaluation of the audiovisual biofeedback system, a multi-institutional study will be performed. Our methodological framework will be based on the widely used Technology Acceptance Model, which gives qualitative scales for two specific variables, perceived usefulness and perceived ease of use, which are fundamental determinants for user acceptance. A total of 75 lung cancer patients will be recruited across seven radiation oncology departments across Australia. Patients will be randomised in a 2:1 ratio, with 2/3 of the patients being recruited into the intervention arm and 1/3 in the control arm. 2:1 randomisation is appropriate as within the interventional arm there is a screening procedure where only patients whose breathing is more regular with audiovisual biofeedback will continue to use this system for their imaging and treatment procedures. Patients within the intervention arm whose free breathing is more regular than audiovisual biofeedback in the screen procedure will remain in the intervention arm of the study but their imaging and treatment procedures will be performed without audiovisual biofeedback. Patients will also be stratified by treating institution and for treatment intent (palliative vs. radical) to ensure similar balance in the arms across the sites. Patients and hospital staff operating the audiovisual biofeedback system will complete questionnaires to assess their experience with audiovisual biofeedback. The objectives of this

State-of-the-art multi-wavelength observations of nearby brightest group/cluster galaxies

Science.gov (United States)

Gendron-Marsolais, Marie-Lou; Hlavacek-Larrondo, Julie

2018-01-01

Nearby galaxy groups and clusters are crucial to our understanding of the impact of nuclear outbursts on the intracluster medium as their proximity allows us to study in detail the processes of feedback from active galactic nuclei in these systems. In this talk, I will present state-of-the-art multi-wavelength observations signatures of this mechanism.I will first show results on multi-configuration 230-470 MHz observations of the Perseus cluster from the Karl G. Jansky Very Large Array, probing the non-thermal emission from the old particle population of the AGN outflows. These observations reveal a multitude of new structures associated with the “mini-halo” and illustrate the high-quality images that can be obtained with the new JVLA at low radio-frequencies.Second, I will present new observations with the optical imaging Fourier transform spectrometer SITELLE (CFHT) of NGC 1275, the Perseus cluster's brightest galaxy. With its wide field of view, it is the only integral field unit spectroscopy instrument able to cover the large emission-line filamentary nebula in NGC 1275. I will present the first detailed velocity map of this nebula in its entirety and tackle the question of its origin (residual cooling flow or dragged gas).Finally, I will present deep Chandra observations of the nearby early-type massive elliptical galaxy NGC 4472, the most optically luminous galaxy in the local Universe, lying on the outskirts of the Virgo cluster. Enhanced X-ray rims around the radio lobes are detected and interpreted as gas uplifted from the core by the buoyant rise of the radio bubbles. We estimate the energy required to lift the gas to constitute a significant fraction of the total outburst energy.I will thus show how these high-fidelity observations of nearby brightest group/cluster galaxies are improving our understanding of the AGN feedback mechanism taking place in galaxy groups and clusters.

High dose melphalan in the treatment of advanced neuroblastoma: results of a randomised trial (ENSG-1) by the European Neuroblastoma Study Group.

Science.gov (United States)

Pritchard, Jon; Cotterill, Simon J; Germond, Shirley M; Imeson, John; de Kraker, Jan; Jones, David R

2005-04-01

High dose myeloablative chemotherapy ("megatherapy"), with haematopoietic stem cell support, is now widely used to consolidate response to induction chemotherapy in patients with advanced neuroblastoma. In this study (European Neuroblastoma Study Group, ENSG1), the value of melphalan myeloablative "megatherapy" was evaluated in a randomised, multi-centre trial. Between 1982 and 1985, 167 children with stages IV and III neuroblastoma (123 stage IV > 1 year old at diagnosis and 44 stage III and stage IV from 6 to 12 months old at diagnosis) were treated with oncovin, cisplatin, epipodophyllotoxin, and cyclophosphamide (OPEC) induction chemotherapy every 3 weeks. After surgical excision of primary tumour, the 90 patients (69% of the total) who achieved complete response (CR) or good partial response (GPR) were eligible for randomisation either to high dose melphalan (180 mg per square meter) with autologous bone marrow support or to no further treatment. Sixty-five (72%) of eligible children were actually randomised and 21 of these patients were surviving at time of this analysis, with median follow-up from randomisation of 14.3 years. Five year event-free survival (EFS) was 38% (95% confidence interval (CI) 21-54%) in the melphalan-treated group and 27% (95% CI 12-42%) in the "no-melphalan" group. This difference was not statistically significant (P = 0.08, log rank test) but for the 48 randomised stage IV patients aged >1 year at diagnosis outcome was significantly better in the melphalan-treated group-5 year EFS 33% versus 17% (P = 0.01, log rank test). In this trial, high dose melphalan improved the length of EFS and overall survival of children with stage IV neuroblastoma >1 year of age who achieved CR or GPR after OPEC induction therapy and surgery. Multi-agent myeloablative regimens are now widely used as consolidation therapy for children with stage IV disease and in those with other disease stages when the MYCN gene copy number in tumour cells is amplified

How to detect trap cluster systems?

International Nuclear Information System (INIS)

Mandowski, Arkadiusz

2008-01-01

Spatially correlated traps and recombination centres (trap-recombination centre pairs and larger clusters) are responsible for many anomalous phenomena that are difficult to explain in the framework of both classical models, i.e. model of localized transitions (LT) and the simple trap model (STM), even with a number of discrete energy levels. However, these 'anomalous' effects may provide a good platform for identifying trap cluster systems. This paper considers selected cluster-type effects, mainly relating to an anomalous dependence of TL on absorbed dose in the system of isolated clusters (ICs). Some consequences for interacting cluster (IAC) systems, involving both localized and delocalized transitions occurring simultaneously, are also discussed

A 10-Week Multimodal Nutrition Education Intervention Improves Dietary Intake among University Students: Cluster Randomised Controlled Trial

Directory of Open Access Journals (Sweden)

Mohd Razif Shahril

2013-01-01

Full Text Available The aim of the study was to evaluate the effectiveness of implementing multimodal nutrition education intervention (NEI to improve dietary intake among university students. The design of study used was cluster randomised controlled design at four public universities in East Coast of Malaysia. A total of 417 university students participated in the study. They were randomly selected and assigned into two arms, that is, intervention group (IG or control group (CG according to their cluster. The IG received 10-week multimodal intervention using three modes (conventional lecture, brochures, and text messages while CG did not receive any intervention. Dietary intake was assessed before and after intervention and outcomes reported as nutrient intakes as well as average daily servings of food intake. Analysis of covariance (ANCOVA and adjusted effect size were used to determine difference in dietary changes between groups and time. Results showed that, compared to CG, participants in IG significantly improved their dietary intake by increasing their energy intake, carbohydrate, calcium, vitamin C and thiamine, fruits and 100% fruit juice, fish, egg, milk, and dairy products while at the same time significantly decreased their processed food intake. In conclusion, multimodal NEI focusing on healthy eating promotion is an effective approach to improve dietary intakes among university students.

Effects of quality improvement in health facilities and community mobilization through women's groups on maternal, neonatal and perinatal mortality in three districts of Malawi: MaiKhanda, a cluster randomized controlled effectiveness trial.

Science.gov (United States)

Colbourn, Tim; Nambiar, Bejoy; Bondo, Austin; Makwenda, Charles; Tsetekani, Eric; Makonda-Ridley, Agnes; Msukwa, Martin; Barker, Pierre; Kotagal, Uma; Williams, Cassie; Davies, Ros; Webb, Dale; Flatman, Dorothy; Lewycka, Sonia; Rosato, Mikey; Kachale, Fannie; Mwansambo, Charles; Costello, Anthony

2013-09-01

Maternal, perinatal and neonatal mortality remains high in low-income countries. We evaluated community and facility-based interventions to reduce deaths in three districts of Malawi. We evaluated a rural participatory women's group community intervention (CI) and a quality improvement intervention at health centres (FI) via a two-by-two factorial cluster randomized controlled trial. Consenting pregnant women were followed-up to 2 months after birth using key informants. Primary outcomes were maternal, perinatal and neonatal mortality. Clusters were health centre catchment areas assigned using stratified computer-generated randomization. Following exclusions, including non-birthing facilities, 61 clusters were analysed: control (17 clusters, 4912 births), FI (15, 5335), CI (15, 5080) and FI + CI (14, 5249). This trial was registered as International Standard Randomised Controlled Trial [ISRCTN18073903]. Outcomes for 14,576 and 20,576 births were recorded during baseline (June 2007-September 2008) and intervention (October 2008-December 2010) periods. For control, FI, CI and FI + CI clusters neonatal mortality rates were 34.0, 28.3, 29.9 and 27.0 neonatal deaths per 1000 live births and perinatal mortality rates were 56.2, 55.1, 48.0 and 48.4 per 1000 births, during the intervention period. Adjusting for clustering and stratification, the neonatal mortality rate was 22% lower in FI + CI than control clusters (OR = 0.78, 95% CI 0.60-1.01), and the perinatal mortality rate was 16% lower in CI clusters (OR = 0.84, 95% CI 0.72-0.97). We did not observe any intervention effects on maternal mortality. Despite implementation problems, a combined community and facility approach using participatory women's groups and quality improvement at health centres reduced newborn mortality in rural Malawi.

Effects of quality improvement in health facilities and community mobilization through women’s groups on maternal, neonatal and perinatal mortality in three districts of Malawi: MaiKhanda, a cluster randomized controlled effectiveness trial

Science.gov (United States)

Colbourn, Tim; Nambiar, Bejoy; Bondo, Austin; Makwenda, Charles; Tsetekani, Eric; Makonda-Ridley, Agnes; Msukwa, Martin; Barker, Pierre; Kotagal, Uma; Williams, Cassie; Davies, Ros; Webb, Dale; Flatman, Dorothy; Lewycka, Sonia; Rosato, Mikey; Kachale, Fannie; Mwansambo, Charles; Costello, Anthony

2016-01-01

Background Maternal, perinatal and neonatal mortality remains high in low-income countries. We evaluated community and facility-based interventions to reduce deaths in three districts of Malawi. Methods We evaluated a rural participatory women’s group community intervention (CI) and a quality improvement intervention at health centres (FI) via a two-by-two factorial cluster randomized controlled trial. Consenting pregnant women were followed-up to 2 months after birth using key informants. Primary outcomes were maternal, perinatal and neonatal mortality. Clusters were health centre catchment areas assigned using stratified computer-generated randomization. Following exclusions, including non-birthing facilities, 61 clusters were analysed: control (17 clusters, 4912 births), FI (15, 5335), CI (15, 5080) and FI + CI (14, 5249). This trial was registered as International Standard Randomised Controlled Trial [ISRCTN18073903]. Outcomes for 14 576 and 20 576 births were recorded during baseline (June 2007–September 2008) and intervention (October 2008–December 2010) periods. Results For control, FI, CI and FI + CI clusters neonatal mortality rates were 34.0, 28.3, 29.9 and 27.0 neonatal deaths per 1000 live births and perinatal mortality rates were 56.2, 55.1, 48.0 and 48.4 per 1000 births, during the intervention period. Adjusting for clustering and stratification, the neonatal mortality rate was 22% lower in FI + CI than control clusters (OR = 0.78, 95% CI 0.60–1.01), and the perinatal mortality rate was 16% lower in CI clusters (OR = 0.84, 95% CI 0.72–0.97). We did not observe any intervention effects on maternal mortality. Conclusions Despite implementation problems, a combined community and facility approach using participatory women’s groups and quality improvement at health centres reduced newborn mortality in rural Malawi. PMID:24030269

Consent: an event or a memory in lumbar spinal surgery? A multi-centre, multi-specialty prospective study of documentation and patient recall of consent content.

Science.gov (United States)

Lo, William B; McAuley, Ciaran P; Gillies, Martin J; Grover, Patrick J; Pereira, Erlick A C

2017-11-01

Prospective, multi-centre, multi-specialty medical notes review and patient interview. The consenting process is an important communication tool which also carries medico-legal implications. While written consent is a pre-requisite before spinal surgery in the UK, the standard and effectiveness of the process have not been assessed previously. This study assesses standard of written consent for elective lumbar decompressive surgery for degenerative disc disease across different regions and specialties in the UK; level of patient recall of the consent content; and identifies factors which affect patient recall. Consent forms of 153 in-patients from 4 centres a, b, c, d were reviewed. Written documentation of intended benefits, alternative treatments and operative risks was assessed. Of them, 108 patients were interviewed within 24 h before or after surgeries to assess recall. The written documentation rates of the operative risks showed significant inter-centre variations in haemorrhage and sphincter disturbance (P = 0.000), but not for others. Analysis of pooled data showed variations in written documentation of risks (P recall of these risks, there was no inter-centre variation. Patients' recall of paralysis as a risk was highest (50.9%) and that of recurrence was lowest (6.5%). Patients recalled risks better than those ≥65, significantly so for infection (29.9 vs 9.7%, P = 0.027). Patients consented >14 days compared to recall for paralysis (65.2 vs 43.7%) and recurrence (17.4 vs 2.8%). Patient recall was independent of consenter grade. Overall, the standard of written consent for elective lumbar spinal decompressive surgery was sub-optimal, which was partly reflected in the poor patient recall. While consenter seniority did not affect patient recall, younger age and longer consent-to-surgery time improved it.

Poor uptake of an online intervention in a cluster randomised controlled trial of online diabetes education for rural general practitioners.

Science.gov (United States)

Paul, Christine L; Piterman, Leon; Shaw, Jonathan E; Kirby, Catherine; Forshaw, Kristy L; Robinson, Jennifer; Thepwongsa, Isaraporn; Sanson-Fisher, Robert W

2017-03-23

In Australia, rural and remote communities have high rates of diabetes-related death and hospitalisation. General practitioners (GPs) play a major role in diabetes detection and management. Education of GPs could optimise diabetes management and improve patient outcomes at a population level. The study aimed to describe the uptake of a continuing medical education intervention for rural GPs and its impact on the viability of a cluster randomised controlled trial of the effects of continuing medical education on whole-town diabetes monitoring and control. Trial design: the cluster randomised controlled trial involved towns as the unit of allocation and analysis with outcomes assessed by de-identified pathology data (not reported here). The intervention programme consisted of an online active learning module, direct electronic access to specialist advice and performance feedback. Multiple rounds of invitation were used to engage GPs with the online intervention content. Evidence-based strategies (e.g. pre-notification, rewards, incentives) were incorporated into the invitations to enrol in the programme. Recruitment to the programme was electronically monitored through the hosting software package during the study intervention period. Eleven matched pairs of towns were included in the study. There were 146 GPs in the 11 intervention towns, of whom 34 (23.3%) enrolled in the programme, and 8 (5.5%) completed the online learning module. No town had more than 10% of the resident GPs complete the learning module. There were no contacts made by GPs regarding requests for specialist advice. Consequently, the trial was discontinued. There is an ongoing need to engage primary care physicians in improving diabetes monitoring and management in rural areas. Online training options, while notionally attractive and accessible, are not likely to have high levels of uptake, even when evidence-based recruitment strategies are implemented. Australian New Zealand Clinical Trials

Recommendations for implementing stereotactic radiotherapy in peripheral stage IA non-small cell lung cancer: report from the Quality Assurance Working Party of the randomised phase III ROSEL study

International Nuclear Information System (INIS)

Hurkmans, Coen W; Cuijpers, Johan P; Lagerwaard, Frank J; Widder, Joachim; Heide, Uulke A van der; Schuring, Danny; Senan, Suresh

2009-01-01

A phase III multi-centre randomised trial (ROSEL) has been initiated to establish the role of stereotactic radiotherapy in patients with operable stage IA lung cancer. Due to rapid changes in radiotherapy technology and evolving techniques for image-guided delivery, guidelines had to be developed in order to ensure uniformity in implementation of stereotactic radiotherapy in this multi-centre study. A Quality Assurance Working Party was formed by radiation oncologists and clinical physicists from both academic as well as non-academic hospitals that had already implemented stereotactic radiotherapy for lung cancer. A literature survey was conducted and consensus meetings were held in which both the knowledge from the literature and clinical experience were pooled. In addition, a planning study was performed in 26 stage I patients, of which 22 were stage 1A, in order to develop and evaluate the planning guidelines. Plans were optimised according to parameters adopted from RTOG trials using both an algorithm with a simple homogeneity correction (Type A) and a more advanced algorithm (Type B). Dose conformity requirements were then formulated based on these results. Based on current literature and expert experience, guidelines were formulated for this phase III study of stereotactic radiotherapy versus surgery. These guidelines can serve to facilitate the design of future multi-centre clinical trials of stereotactic radiotherapy in other patient groups and aid a more uniform implementation of this technique outside clinical trials

Quit in General Practice: a cluster randomised trial of enhanced in-practice support for smoking cessation

Directory of Open Access Journals (Sweden)

Zwar Nicholas

2010-08-01

Full Text Available Abstract Background This study will test the uptake and effectiveness of a flexible package of smoking cessation support provided primarily by the practice nurse (PN and tailored to meet the needs of a diversity of patients. Methods/Design This study is a cluster randomised trial, with practices allocated to one of three groups 1 Quit with Practice Nurse 2 Quitline referral 3 GP usual care. PNs from practices randomised to the intervention group will receive a training course in smoking cessation followed by access to mentoring. GPs from practices randomised to the Quitline referral group will receive information about the study and the process of written referral and GPs in the usual care group will receive information about the study. Eligible patients are those aged 18 and over presenting to their GP who are daily or weekly smokers and who are able to give informed consent. Patients on low incomes in all three groups will be able to access free nicotine patches. Primary outcomes are sustained abstinence and point prevalence abstinence at the three month and 12 month follow-up points; and incremental cost effectiveness ratios at 12 months. Process evaluation on the reach and acceptability of the intervention approached will be collected through Computer Assisted Telephone Interviews (CATI with patients and semi-structured interviews with PNs and GPs. The primary analysis will be by intention to treat. Cessation outcomes will be compared between the three arms at three months and 12 month follow-up using multiple logistic regression. The incremental cost effectiveness ratios will be estimated for the 12 month quit rate for the intervention groups compared to usual care and to each other. Analysis of qualitative data on process outcomes will be based on thematic analysis. Discussion High quality evidence on effectiveness of practice nurse interventions is needed to inform health policy on development of practice nurse roles. If effective

Thermodynamically accessible titanium clusters TiN, N = 2-32.

Science.gov (United States)

Lazauskas, Tomas; Sokol, Alexey A; Buckeridge, John; Catlow, C Richard A; Escher, Susanne G E T; Farrow, Matthew R; Mora-Fonz, David; Blum, Volker W; Phaahla, Tshegofatso M; Chauke, Hasani R; Ngoepe, Phuti E; Woodley, Scott M

2018-05-10

We have performed a genetic algorithm search on the tight-binding interatomic potential energy surface (PES) for small TiN (N = 2-32) clusters. The low energy candidate clusters were further refined using density functional theory (DFT) calculations with the PBEsol exchange-correlation functional and evaluated with the PBEsol0 hybrid functional. The resulting clusters were analysed in terms of their structural features, growth mechanism and surface area. The results suggest a growth mechanism that is based on forming coordination centres by interpenetrating icosahedra, icositetrahedra and Frank-Kasper polyhedra. We identify centres of coordination, which act as centres of bulk nucleation in medium sized clusters and determine the morphological features of the cluster.

Multi-professional clinical medication reviews in care homes for the elderly: study protocol for a randomised controlled trial with cost effectiveness analysis

Directory of Open Access Journals (Sweden)

Sach Tracey

2011-10-01

Full Text Available Abstract Background Evidence demonstrates that measures are needed to optimise therapy and improve administration of medicines in care homes for older people. The aim of this study is to determine the clinical and cost effectiveness of a novel model of multi-professional medication review. Methods A cluster randomised controlled trial design, involving thirty care homes. In line with current practice in medication reviews, recruitment and consent will be sought from general practitioners and care homes, rather than individual residents. Care homes will be segmented according to size and resident mix and allocated to the intervention arm (15 homes or control arm (15 homes sequentially using minimisation. Intervention homes will receive a multi-professional medication review at baseline and at 6 months, with follow-up at 12 months. Control homes will receive usual care (support they currently receive from the National Health Service, with data collection at baseline and 12 months. The novelty of the intervention is a review of medications by a multi-disciplinary team. Primary outcome measures are number of falls and potentially inappropriate prescribing. Secondary outcome measures include medication costs, health care resource use, hospitalisations and mortality. The null hypothesis proposes no difference in primary outcomes between intervention and control patients. The primary outcome variable (number of falls will be analysed using a linear mixed model, with the intervention specified as a fixed effect and care homes included as a random effect. Analyses will be at the level of the care home. The economic evaluation will estimate the cost-effectiveness of the intervention compared to usual care from a National Health Service and personal social services perspective. The study is not measuring the impact of the intervention on professional working relationships, the medicines culture in care homes or the generic health-related quality of life of

The role of dosimetry audit in lung SBRT multi-centre clinical trials.

Science.gov (United States)

Clark, Catharine H; Hurkmans, Coen W; Kry, Stephen F

2017-12-01

Stereotactic Body Radiotherapy (SBRT) in the lung is a challenging technique which requires high quality clinical trials to answer the un-resolved clinical questions. Quality assurance of these clinical trials not only ensures the safety of the treatment of the participating patients but also minimises the variation in treatment, thus allowing the lowest number of patient treatments to answer the trial question. This review addresses the role of dosimetry audits in the quality assurance process and considers what can be done to ensure the highest accuracy of dose calculation and delivery and it's assessment in multi-centre trials. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

A cluster-randomised trial of staff education to improve the quality of life of people with dementia living in residential care: the DIRECT study.

Directory of Open Access Journals (Sweden)

Christopher Beer

Full Text Available BACKGROUND: The Dementia In Residential care: EduCation intervention Trial (DIRECT was conducted to determine if delivery of education designed to meet the perceived need of GPs and care staff improves the quality of life of participants with dementia living in residential care. METHODOLOGY/PRINCIPAL FINDINGS: This cluster-randomised controlled trial was conducted in 39 residential aged care facilities in the metropolitan area of Perth, Western Australia. 351 care facility residents aged 65 years and older with Mini-Mental State Examination ≤ 24, their GPs and facility staff participated. Flexible education designed to meet the perceived needs of learners was delivered to GPs and care facility staff in intervention groups. The primary outcome of the study was self-rated quality of life of participants with dementia, measured using the QOL-Alzheimer's Disease Scale (QOL-AD at 4 weeks and 6 months after the conclusion of the intervention. Analysis accounted for the effect of clustering by using multi-level regression analysis. Education of GPs or care facility staff did not affect the primary outcome at either 4 weeks or 6 months. In a post hoc analysis excluding facilities in which fewer than 50% of staff attended an education session, self-rated QOL-AD scores were 6.14 points (adjusted 95%CI 1.14, 11.15 higher at four-week follow-up among residents in facilities randomly assigned to the education intervention. CONCLUSION: The education intervention directed at care facilities or GPs did not improve the quality of life ratings of participants with dementia as a group. This may be explained by the poor adherence to the intervention programme, as participants with dementia living in facilities where staff participated at least minimally seemed to benefit. TRIAL REGISTRATION: ANZCTR.org.au ACTRN12607000417482.

A cluster-randomised trial of staff education to improve the quality of life of people with dementia living in residential care: the DIRECT study.

Science.gov (United States)

Beer, Christopher; Horner, Barbara; Flicker, Leon; Scherer, Samuel; Lautenschlager, Nicola T; Bretland, Nick; Flett, Penelope; Schaper, Frank; Almeida, Osvaldo P

2011-01-01

The Dementia In Residential care: EduCation intervention Trial (DIRECT) was conducted to determine if delivery of education designed to meet the perceived need of GPs and care staff improves the quality of life of participants with dementia living in residential care. This cluster-randomised controlled trial was conducted in 39 residential aged care facilities in the metropolitan area of Perth, Western Australia. 351 care facility residents aged 65 years and older with Mini-Mental State Examination ≤ 24, their GPs and facility staff participated. Flexible education designed to meet the perceived needs of learners was delivered to GPs and care facility staff in intervention groups. The primary outcome of the study was self-rated quality of life of participants with dementia, measured using the QOL-Alzheimer's Disease Scale (QOL-AD) at 4 weeks and 6 months after the conclusion of the intervention. Analysis accounted for the effect of clustering by using multi-level regression analysis. Education of GPs or care facility staff did not affect the primary outcome at either 4 weeks or 6 months. In a post hoc analysis excluding facilities in which fewer than 50% of staff attended an education session, self-rated QOL-AD scores were 6.14 points (adjusted 95%CI 1.14, 11.15) higher at four-week follow-up among residents in facilities randomly assigned to the education intervention. The education intervention directed at care facilities or GPs did not improve the quality of life ratings of participants with dementia as a group. This may be explained by the poor adherence to the intervention programme, as participants with dementia living in facilities where staff participated at least minimally seemed to benefit. ANZCTR.org.au ACTRN12607000417482.

Effect of osteosynthesis, primary hemiarthroplasty, and non-surgical management for displaced four-part fractures of the proximal humerus in elderly: a multi-centre, randomised clinical trial

DEFF Research Database (Denmark)

Brorson, Stig; Olsen, Bo Sanderhoff; Frich, Lars Henrik

2009-01-01

BACKGROUND: Fractures of the proximal humerus are common injuries and account for 4-5 percent of all fractures, second only to hip and wrist fractures. The incidence is positively correlated with age and osteoporosis, and is likely to increase. Displaced four-part fractures are among the most...... severe injuries, accounting for 2-10 percent of proximal humeral fractures. The optimal intervention is disputed. Two previous randomised trials were very small and involved a noticeable risk of bias, and systematic reviews consequently conclude that there is inadequate basis for evidence-based treatment...... ten national shoulder units within a two-year period. We plan to include 162 patients. A central randomisation unit will allocate patients. All patients will receive a standardised three-month rehabilitation program of supervised physiotherapy regardless of treatment allocation. Patients...

Effectiveness of job rotation for preventing work-related musculoskeletal diseases: a cluster randomised controlled trial.

Science.gov (United States)

Comper, Maria Luiza Caires; Dennerlein, Jack Tigh; Evangelista, Gabriela Dos Santos; Rodrigues da Silva, Patricia; Padula, Rosimeire Simprini

2017-08-01

Job rotation is an organisational strategy widely used on assembly lines in manufacturing industries to mitigate workers' exposure so as to prevent musculoskeletal disorders. This study aimed to evaluate the effectiveness of job rotation for reducing working hours lost due to sick leave resulting from musculoskeletal diseases. The design consisted of a 1-year cluster randomised controlled trial with a blinded assessor. Production sectors of the textile industry were randomised to intervention and control groups. Both groups received ergonomic training. The intervention group performed a job rotation programme. The primary outcome measure was number of working hours lost due to sick leave as a result of musculoskeletal disease (ICD-10). The secondary outcome measures were musculoskeletal symptoms (Yes/No), risk factors for musculoskeletal diseases (0-10), psychosocial factors and fatigue (0-100), general health (0-100), and productivity (0-10). All secondary outcomes were measured at baseline and 12-month follow-up. At the 12-month follow-up, both groups showed an increase in the number of working hours lost due to sick leave for musculoskeletal disease. There was no significant difference between the job rotation intervention group (mean deviation -5.6 hours, 95% CI -25.0 to 13.8) at the 12-month follow-up and the control group. There were no significant differences between groups for the secondary outcomes (p>0.05). The job rotation programme was not effective in reducing the number of working hours lost due to sick leave, decreasing the prevalence of musculoskeletal symptoms, or improving perception of musculoskeletal pain and workplace risk factors, psychosocial risk factors and productivity. NCT01979731. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The Irish DAFNE study protocol: a cluster randomised trial of group versus individual follow-up after structured education for type 1 diabetes.

LENUS (Irish Health Repository)

Dinneen, Seán F

2009-01-01

BACKGROUND: Structured education programmes for individuals with Type 1 diabetes have become a recognised means of delivering the knowledge and skills necessary for optimal self-management of the condition. The Dose Adjustment for Normal Eating (DAFNE) programme has been shown to improve biomedical (HbA(1c) and rates of severe hypoglycaemia) and psychosocial outcomes for up to 12 months following course delivery. The optimal way to support DAFNE graduates and maintain the benefits of the programme has not been established. We aimed to compare 2 different methods of follow-up of DAFNE graduates in a pragmatic clinical trial delivered in busy diabetes clinics on the island of Ireland. METHODS: Six participating centres were cluster randomised to deliver either group follow-up or a return to traditional one-to-one clinic visits. In the intervention arm group follow-up was delivered at 6 and 12 months post DAFNE training according to a curriculum developed for the study. In the control arm patients were seen individually in diabetes clinics as part of routine care. Study outcomes included HbA(1c) levels, self-reported rates of severe hypoglycaemia, body weight and measures of diabetes wellbeing and quality of life. These were measured at 6, 12 and 18 months after recruitment. Generalisability (external validity) was maximised by recruiting study participants from existing DAFNE waiting lists in each centre, by using broad inclusion criteria (including HbA(1c) values less than 13 percent with no lower limit) and by using existing clinic staff to deliver the training and follow-up. Internal validity and treatment fidelity were maximised by quality assuring the training of all DAFNE educators, by external peer review of the group follow-up sessions and by striving for full attendance at follow-up visits. Assays of HbA(1c) were undertaken in a central laboratory. DISCUSSION: This pragmatic clinical trial evaluating group follow-up after a structured education programme has

The additional value of a night splint to eccentric exercises in chronic midportion Achilles tendinopathy: a randomised controlled trial

NARCIS (Netherlands)

de Vos, R. J.; Weir, A.; Visser, R. J. A.; de Winter, ThC; Tol, J. L.

2007-01-01

To assess whether the use of a night splint is of added benefit on functional outcome in treating chronic midportion Achilles tendinopathy. This was a single-blind, prospective, single centre, randomised controlled trial set in the Sports Medical Department, The Hague Medical Centre, The

Effectiveness of structured patient-clinician communication with a solution focused approach (DIALOG+) in community treatment of patients with psychosis ? a cluster randomised controlled trial

OpenAIRE

Priebe, Stefan; Kelley, Lauren; Golden, Eoin; McCrone, Paul; Kingdon, David; Rutterford, Clare; McCabe, Rosemarie

2013-01-01

Background Large numbers of patients with psychosis have regular meetings with key clinicians in the community. There is little evidence on how these meetings should be conducted to be therapeutically effective. DIALOG, a computer mediated procedure, was shown to improve outcomes in a European multi-centre trial. DIALOG structures the patient-clinician communication and makes it patient-centred, but does not guide clinicians as to how to respond to patients? concerns. DIALOG has been further ...

Harmonization process and reliability assessment of anthropometric measurements in the elderly EXERNET multi-centre study.

Directory of Open Access Journals (Sweden)

Alba Gómez-Cabello

Full Text Available BACKGROUND: The elderly EXERNET multi-centre study aims to collect normative anthropometric data for old functionally independent adults living in Spain. PURPOSE: To describe the standardization process and reliability of the anthropometric measurements carried out in the pilot study and during the final workshop, examining both intra- and inter-rater errors for measurements. MATERIALS AND METHODS: A total of 98 elderly from five different regions participated in the intra-rater error assessment, and 10 different seniors living in the city of Toledo (Spain participated in the inter-rater assessment. We examined both intra- and inter-rater errors for heights and circumferences. RESULTS: For height, intra-rater technical errors of measurement (TEMs were smaller than 0.25 cm. For circumferences and knee height, TEMs were smaller than 1 cm, except for waist circumference in the city of Cáceres. Reliability for heights and circumferences was greater than 98% in all cases. Inter-rater TEMs were 0.61 cm for height, 0.75 cm for knee-height and ranged between 2.70 and 3.09 cm for the circumferences measured. Inter-rater reliabilities for anthropometric measurements were always higher than 90%. CONCLUSION: The harmonization process, including the workshop and pilot study, guarantee the quality of the anthropometric measurements in the elderly EXERNET multi-centre study. High reliability and low TEM may be expected when assessing anthropometry in elderly population.

Prevalence of maternal anaemia and its predictors: a multi-centre study.

Science.gov (United States)

Barroso, Filipa; Allard, Shubha; Kahan, Brennan C; Connolly, Catriona; Smethurst, Heather; Choo, Louise; Khan, Khalid; Stanworth, Simon

2011-11-01

To investigate the prevalence, predictors, and management of anaemia in pregnancy. A multi centre study across 11 maternity units in the UK. Data were collected over a two week study period in 2008 on maternal history, haemoglobin (Hb) and ferritin concentrations, iron therapy during pregnancy and in the postpartum period. Logistic regression models were used to explore factors associated with anaemia during pregnancy. Main outcomes included anaemia, defined as Hbanaemia by 32 weeks gestation included young maternal age (odds ratio 1.96, 95% CI 1.38-2.79), non-white ethnic origin (odds ratios varied 1.37-2.89 depending on ethnic origin) and increasing parity (odds ratio 1.24, 95% CI 1.08-1.41). Of women who had postnatal Hb levels checked, 30% (309/1031) were anaemic and, depending on centre, 16% to 86% of these received iron therapy. Anaemia was reported in nearly one in four women in the antenatal period, and nearly one in three of the women who had a postpartum Hb checked. Despite national guidelines, there was considerable variation in administration of iron including low utilisation of parenteral iron therapy. Future research needs to focus on the consequences of iron deficiency anaemia for maternal and infant health outcomes and effectiveness of implementation strategies to reduce anaemia. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Feasibility of a patient-centred nutrition intervention to improve oral intakes of patients at risk of pressure ulcer: a pilot randomised control trial.

Science.gov (United States)

Roberts, Shelley; Desbrow, Ben; Chaboyer, Wendy

2016-06-01

Nutrition is important for pressure ulcer prevention. This randomised control pilot study assessed the feasibility of conducting a larger trial to test the effectiveness of a patient-centred intervention for improving the dietary intakes of patients at risk of pressure ulcer in hospital. A 3-day intervention targeting patients at risk of pressure ulcer was developed, based on three main foundations: patient education, patient participation and guided goal setting. The intervention was piloted in three wards in a metropolitan hospital in Queensland, Australia. Participants were randomised into control or intervention groups and had their oral intakes monitored. A subset of intervention patients was interviewed on their perceptions of the intervention. Feasibility was tested against three criteria: ≥75% recruitment; ≥80% retention; and ≥80% intervention fidelity. Secondary outcomes related to effects on energy and protein intakes. Eighty patients participated in the study and 66 were included in final analysis. The recruitment rate was 82%, retention rate was 88%, and 100% of intervention patients received the intervention. Patients viewed the intervention as motivating and met significantly more of their estimated energy and protein requirements over time. This pilot study indicates that the intervention is feasible and acceptable by patients at risk of pressure ulcer. A larger trial is needed to confirm the effectiveness of the intervention in the clinical setting. © 2015 Nordic College of Caring Science.

Study protocol of effectiveness of a biopsychosocial multidisciplinary intervention in the evolution of non-speficic sub-acute low back pain in the working population: cluster randomised trial

Directory of Open Access Journals (Sweden)

Roura-Olivan Mercè

2010-01-01

Full Text Available Abstract Background Non-specific low back pain is a common cause for consultation with the general practitioner, generating increased health and social costs. This study will analyse the effectiveness of a multidisciplinary intervention to reduce disability, severity of pain, anxiety and depression, to improve quality of life and to reduce the incidence of chronic low back pain in the working population with non-specific low back pain, compared to usual clinical care. Methods/Design A Cluster randomised clinical trial will be conducted in 38 Primary Health Care Centres located in Barcelona, Spain and its surrounding areas. The centres are randomly allocated to the multidisciplinary intervention or to usual clinical care. Patients between 18 and 65 years old (n = 932; 466 per arm and with a diagnostic of a non-specific sub-acute low back pain are included. Patients in the intervention group are receiving the recommendations of clinical practice guidelines, in addition to a biopsychosocial multidisciplinary intervention consisting of group educational sessions lasting a total of 10 hours. The main outcome is change in the score in the Roland Morris disability questionnaire at three months after onset of pain. Other outcomes are severity of pain, quality of life, duration of current non-specific low back pain episode, work sick leave and duration, Fear Avoidance Beliefs and Goldberg Questionnaires. Outcomes will be assessed at baseline, 3, 6 and 12 months. Analysis will be by intention to treat. The intervention effect will be assessed through the standard error of measurement and the effect-size. Responsiveness of each scale will be evaluated by standardised response mean and receiver-operating characteristic method. Recovery according to the patient will be used as an external criterion. A multilevel regression will be performed on repeated measures. The time until the current episode of low back pain takes to subside will be analysed by Cox

Optimization Approach for Multi-scale Segmentation of Remotely Sensed Imagery under k-means Clustering Guidance

Directory of Open Access Journals (Sweden)

WANG Huixian

2015-05-01

Full Text Available In order to adapt different scale land cover segmentation, an optimized approach under the guidance of k-means clustering for multi-scale segmentation is proposed. At first, small scale segmentation and k-means clustering are used to process the original images; then the result of k-means clustering is used to guide objects merging procedure, in which Otsu threshold method is used to automatically select the impact factor of k-means clustering; finally we obtain the segmentation results which are applicable to different scale objects. FNEA method is taken for an example and segmentation experiments are done using a simulated image and a real remote sensing image from GeoEye-1 satellite, qualitative and quantitative evaluation demonstrates that the proposed method can obtain high quality segmentation results.

Effectiveness and cost-effectiveness of an educational intervention for practice teams to deliver problem focused therapy for insomnia: rationale and design of a pilot cluster randomised trial

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Ørner Roderick

2009-01-01

Full Text Available Abstract Background Sleep problems are common, affecting over a third of adults in the United Kingdom and leading to reduced productivity and impaired health-related quality of life. Many of those whose lives are affected seek medical help from primary care. Drug treatment is ineffective long term. Psychological methods for managing sleep problems, including cognitive behavioural therapy for insomnia (CBTi have been shown to be effective and cost effective but have not been widely implemented or evaluated in a general practice setting where they are most likely to be needed and most appropriately delivered. This paper outlines the protocol for a pilot study designed to evaluate the effectiveness and cost-effectiveness of an educational intervention for general practitioners, primary care nurses and other members of the primary care team to deliver problem focused therapy to adult patients presenting with sleep problems due to lifestyle causes, pain or mild to moderate depression or anxiety. Methods and design This will be a pilot cluster randomised controlled trial of a complex intervention. General practices will be randomised to an educational intervention for problem focused therapy which includes a consultation approach comprising careful assessment (using assessment of secondary causes, sleep diaries and severity and use of modified CBTi for insomnia in the consultation compared with usual care (general advice on sleep hygiene and pharmacotherapy with hypnotic drugs. Clinicians randomised to the intervention will receive an educational intervention (2 × 2 hours to implement a complex intervention of problem focused therapy. Clinicians randomised to the control group will receive reinforcement of usual care with sleep hygiene advice. Outcomes will be assessed via self-completion questionnaires and telephone interviews of patients and staff as well as clinical records for interventions and prescribing. Discussion Previous studies in adults

Does it matter if clinicians recruiting for a trial don't understand what the trial is really about? Qualitative study of surgeons' experiences of participation in a pragmatic multi-centre RCT

Directory of Open Access Journals (Sweden)

Snowdon Claire

2007-01-01

Full Text Available Abstract Background Qualitative methods are increasingly used to study the process of clinical trials and patients understanding of the rationale for trials, randomisation and reasons for taking part or refusing. Patients' understandings are inevitably influenced by the recruiting clinician's understanding of the trial, yet relatively little qualitative work has explored clinicians' perceptions and understandings of trials. This study interviewed surgeons shortly after the multi-centre, pragmatic RCT in which they had participated had been completed. Methods We used in-depth interviews with surgeons who participated in the Spine Stabilisation Trial (a pragmatic RCT to explore their understanding of the trial purpose and how this understanding had influenced their recruitment procedures and interpretation of the results. A purposive sample of eleven participating surgeons was chosen from 8 of the 15 UK trial centres. Results Although the surgeons thought that the trial was addressing an important question there was little agreement about what this question was: although it was a trial of 'equivalent' treatments, some thought that it was a trial of surgery, others a trial of rehabilitation and others that it was exploring what to do with patients in whom all other treatment options had been unsuccessful. The surgeons we interviewed were not aware of the rationale for the pragmatic inclusion criteria and nearly all were completely baffled about the meaning of 'equipoise'. Misunderstandings about the entry criteria were an important source of confusion about the results and led to reluctance to apply the results to their own practice. Conclusion The study suggests several lessons for the conduct of future multi-centre trials. Recruiting surgeons (and other clinicians may not be familiar with the rationale for pragmatic designs and may need to be regularly reminded about the purpose during the study. Reassurance may be necessary that a pragmatic

Assessment of community-level effects of intermittent preventive treatment for malaria in schoolchildren in Jinja, Uganda (START-IPT trial): a cluster-randomised trial.

Science.gov (United States)

Staedke, Sarah G; Maiteki-Sebuguzi, Catherine; Rehman, Andrea M; Kigozi, Simon P; Gonahasa, Samuel; Okiring, Jaffer; Lindsay, Steve W; Kamya, Moses R; Chandler, Clare I R; Dorsey, Grant; Drakeley, Chris

2018-06-01

Intermittent preventive treatment (IPT) is a well established malaria control intervention. Evidence that delivering IPT to schoolchildren could provide community-level benefits is limited. We did a cluster-randomised controlled trial to assess the effect of IPT of primary schoolchildren with dihydroartemisinin-piperaquine (DP) on indicators of malaria transmission in the community, in Jinja, Uganda. We included 84 clusters, each comprising one primary school and the 100 closest available households. The clusters were randomly assigned 1:1 to receive IPT with DP or standard care (control) by restricted randomisation to ensure balance by geography and school type. Children in intervention schools received IPT monthly for up to six rounds (June to December, 2014). We did cross-sectional community surveys in randomly selected households at baseline and in January to April, 2015, during which we measured participants' temperatures and obtained finger-prick blood smears for measurement of parasite prevalence by microscopy. We also did entomological surveys 1 night per month in households from 20 randomly selected IPT and 20 control clusters. The primary trial outcome was parasite prevalence in the final community survey. The primary entomological survey outcome was the annual entomological inoculation rate (aEIR) from July, 2014, to April, 2015. This trial is registered at ClinicalTrials.gov, number NCT02009215. Among 23 280 students registered in the 42 intervention schools, 10 079 (43%) aged 5-20 years were enrolled and received at least one dose of DP. 9286 (92%) of 10 079 received at least one full course of DP (three doses). Community-level parasite prevalence was lower in the intervention clusters than in the control clusters (19% vs 23%, adjusted risk ratio 0·85, 95% CI 0·73-1·00, p=0·05). The aEIR was lower in the intervention group than in the control group, but not significantly so (10·1 vs 15·2 infective bites per person, adjusted incidence rate

An intermediate-mass black hole in the centre of the globular cluster 47 Tucanae.

Science.gov (United States)

Kızıltan, Bülent; Baumgardt, Holger; Loeb, Abraham

2017-02-08

Intermediate-mass black holes should help us to understand the evolutionary connection between stellar-mass and super-massive black holes. However, the existence of intermediate-mass black holes is still uncertain, and their formation process is therefore unknown. It has long been suspected that black holes with masses 100 to 10,000 times that of the Sun should form and reside in dense stellar systems. Therefore, dedicated observational campaigns have targeted globular clusters for many decades, searching for signatures of these elusive objects. All candidate signatures appear radio-dim and do not have the X-ray to radio flux ratios required for accreting black holes. Based on the lack of an electromagnetic counterpart, upper limits of 2,060 and 470 solar masses have been placed on the mass of a putative black hole in 47 Tucanae (NGC 104) from radio and X-ray observations, respectively. Here we show there is evidence for a central black hole in 47 Tucanae with a mass of solar masses when the dynamical state of the globular cluster is probed with pulsars. The existence of an intermediate-mass black hole in the centre of one of the densest clusters with no detectable electromagnetic counterpart suggests that the black hole is not accreting at a sufficient rate to make it electromagnetically bright and therefore, contrary to expectations, is gas-starved. This intermediate-mass black hole might be a member of an electromagnetically invisible population of black holes that grow into supermassive black holes in galaxies.

Delivering prevention for alcohol and cannabis using the Internet: a cluster randomised controlled trial.

Science.gov (United States)

Newton, Nicola C; Andrews, Gavin; Teesson, Maree; Vogl, Laura E

2009-06-01

To establish the efficacy of an internet based prevention program to reduce alcohol and cannabis use in adolescents. A cluster randomised controlled trial was conducted with 764 13-year olds from ten Australian secondary schools in 2007-2008. Half the schools were randomly allocated to the computerised prevention program (n=397), and half to their usual health classes (n=367). The Climate Schools: Alcohol and Cannabis prevention course is facilitated by the internet and consists of novel, evidence-based, curriculum consistent lessons aimed at reducing alcohol and cannabis use. Participants were assessed at baseline, immediately post, and at six months following the intervention. Compared to the control group, students in the intervention group showed significant improvements in alcohol and cannabis knowledge at the end of the course and the six month follow-up. In addition, the intervention group showed a reduction in average weekly alcohol consumption and frequency of cannabis use at the six month follow-up. No differences between groups were found on alcohol expectancies, cannabis attitudes, or alcohol and cannabis related harms. The course is acceptable, scalable and fidelity is assured. It increased knowledge regarding alcohol and cannabis, and decreased use of these drugs.

A patient-centred team-coaching concept for medical rehabilitation.

Science.gov (United States)

Körner, M; Becker, S; Dinius, J; Müller, C; Zimmermann, L; Rundel, M

2018-01-01

Team coaching enhances teamwork and subsequently improves patient-centredness in medical rehabilitation clinics. Even though interprofessional teamwork is regarded as a crucial factor in medical rehabilitation, to date no evaluated team-coaching approaches are available for improving interprofessional teamwork in medical rehabilitation in Germany. Based on a systematic literature search and interviews with staff, managers, and patients of rehabilitation clinics, we developed a team-coaching approach that is standardized in its process but based on the individual needs and requests of each clinic. It takes a systemic perspective and is goal-oriented and solution-focused. The approach mainly serves to provide impulses to make use of resources within the team and to support a self-directed organisational learning process. It is manualized and can, therefore, be used by professionals aiming to improve interprofessional teamwork in their clinic. A multi-centre, cluster-randomized controlled study that was conducted to evaluate the team-coaching approach showed positive results. Team organization, knowledge integration, and responsibility can be improved, and, therefore, the implementation of the patient-centred team-coaching approach in interprofessional rehabilitation teams can be recommended.

Pilot cluster randomised controlled trial of flooring to reduce injuries from falls in wards for older people.

Science.gov (United States)

Drahota, Amy Kim; Ward, Derek; Udell, Julie E; Soilemezi, Dia; Ogollah, Reuben; Higgins, Bernard; Dean, Taraneh P; Severs, Martin

2013-09-01

falls disproportionately affect older people, who are at increased risk of falls and injury. This pilot study investigates shock-absorbing flooring for fall-related injuries in wards for frail older people. we conducted a non-blinded cluster randomised trial in eight hospitals in England between April 2010 and August 2011. Each site allocated one bay as the 'study area', which was randomised via computer to intervention (8.3-mm thick Tarkett Omnisports EXCEL) or control (2-mm standard in situ flooring). Sites had an intervention period of 1 year. Anybody admitted to the study area was eligible. The primary outcome was the fall-related injury rate. Secondary outcomes were injury severity, fall rate and adverse events. during the intervention period, 226 participants were recruited to each group (219 and 223 were analysed in the intervention and control group, respectively). Of 35 falls (31 fallers) in the intervention group, 22.9% were injurious, compared with 42.4% of 33 falls (22 fallers) in the control group [injury incident rate ratio (IRR) = 0.58, 95% CI = 0.18-1.91]. There were no moderate or major injuries in the intervention group and six in the control group. The fall IRR was 1.07 (95% CI = 0.64-1.81). Staff at intervention sites raised concerns about pushing equipment, documenting one pulled back. future research should assess shock-absorbing flooring with better 'push/pull' properties and explore increased faller risk. We estimate a future trial will need 33,480-52,840 person bed-days per arm.

Multi-technology control centre to integrate 460 MW renewables

International Nuclear Information System (INIS)

2016-01-01

The new RWE Innogy Aersa Control Centre that has been certified to act as an interface with CECRE (the Renewable Energy Control Centre) since February 2015, connects RWE’s 20 renewable energy facilities with REE, the Spanish Electricity Grid. As a result, it ensures that wind farms, in addition to hydropower and solar plants, can inject the energy generated by its 460 MW installed safely and with no penalties. Green Eagle Solutions, a provider of software solutions for renewable energy companies, has collaborated with RWE in the development of this Control Centre, meeting the high standards of quality and safety required by RWE. This centre uses CompactSCADA® technology to integrate power generation facilities that need to be integrated in a Control Centre to communicate with REE’s CECRE. (Author)

Heterogeneous FDG-guided dose-escalation for locally advanced NSCLC (the NARLAL2 trial): Design and early dosimetric results of a randomized, multi-centre phase-III study

DEFF Research Database (Denmark)

Møller, Ditte Sloth; Nielsen, Tine Bjørn; Brink, Carsten

2017-01-01

Background and purpose: Local recurrence is frequent in locally advanced NSCLC and is primarily located in FDG-avid parts of tumour and lymph nodes. Aiming at improving local control without increasing toxicity, we designed a multi-centre phase-III trial delivering inhomogeneous dose-escalation d......Background and purpose: Local recurrence is frequent in locally advanced NSCLC and is primarily located in FDG-avid parts of tumour and lymph nodes. Aiming at improving local control without increasing toxicity, we designed a multi-centre phase-III trial delivering inhomogeneous dose...

Study protocol of cost-effectiveness and cost-utility of a biopsychosocial multidisciplinary intervention in the evolution of non-specific sub-acute low back pain in the working population: cluster randomised trial

Directory of Open Access Journals (Sweden)

de Kort Nelleke

2011-08-01

Full Text Available Abstract Background Low back pain (LBP, with high incidence and prevalence rate, is one of the most common reasons to consult the health system and is responsible for a significant amount of sick leave, leading to high health and social costs. The objective of the study is to assess the cost-effectiveness and cost-utility analysis of a multidisciplinary biopsychosocial educational group intervention (MBEGI of non-specific sub-acute LBP in comparison with the usual care in the working population recruited in primary healthcare centres. Methods/design The study design is a cost-effectiveness and cost-utility analysis of a MBEGI in comparison with the usual care of non-specific sub-acute LBP. Measures on effectiveness and costs of both interventions will be obtained from a cluster randomised controlled clinical trial carried out in 38 Catalan primary health care centres, enrolling 932 patients between 18 and 65 years old with a diagnosis of non-specific sub-acute LBP. Effectiveness measures are: pharmaceutical treatments, work sick leave (% and duration in days, Roland Morris disability, McGill pain intensity, Fear Avoidance Beliefs (FAB and Golberg Questionnaires. Utility measures will be calculated from the SF-12. The analysis will be performed from a social perspective. The temporal horizon is at 3 months (change to chronic LBP and 12 months (evaluate the outcomes at long term. Assessment of outcomes will be blinded and will follow the intention-to-treat principle. Discussion We hope to demonstrate the cost-effectiveness and cost-utility of MBEGI, see an improvement in the patients' quality of life, achieve a reduction in the duration of episodes and the chronicity of non-specific low back pain, and be able to report a decrease in the social costs. If the intervention is cost-effectiveness and cost-utility, it could be applied to Primary Health Care Centres. Trial registration ISRCTN: ISRCTN58719694

A Multi-Hop Clustering Mechanism for Scalable IoT Networks.

Science.gov (United States)

Sung, Yoonyoung; Lee, Sookyoung; Lee, Meejeong

2018-03-23

It is expected that up to 26 billion Internet of Things (IoT) equipped with sensors and wireless communication capabilities will be connected to the Internet by 2020 for various purposes. With a large scale IoT network, having each node connected to the Internet with an individual connection may face serious scalability issues. The scalability problem of the IoT network may be alleviated by grouping the nodes of the IoT network into clusters and having a representative node in each cluster connect to the Internet on behalf of the other nodes in the cluster instead of having a per-node Internet connection and communication. In this paper, we propose a multi-hop clustering mechanism for IoT networks to minimize the number of required Internet connections. Specifically, the objective of proposed mechanism is to select the minimum number of coordinators, which take the role of a representative node for the cluster, i.e., having the Internet connection on behalf of the rest of the nodes in the cluster and to map a partition of the IoT nodes onto the selected set of coordinators to minimize the total distance between the nodes and their respective coordinator under a certain constraint in terms of maximum hop count between the IoT nodes and their respective coordinator. Since this problem can be mapped into a set cover problem which is known as NP-hard, we pursue a heuristic approach to solve the problem and analyze the complexity of the proposed solution. Through a set of experiments with varying parameters, the proposed scheme shows 63-87.3% reduction of the Internet connections depending on the number of the IoT nodes while that of the optimal solution is 65.6-89.9% in a small scale network. Moreover, it is shown that the performance characteristics of the proposed mechanism coincide with expected performance characteristics of the optimal solution in a large-scale network.

Effect of an interactive therapeutic robotic animal on engagement, mood states, agitation and psychotropic drug use in people with dementia: a cluster-randomised controlled trial protocol.

Science.gov (United States)

Moyle, Wendy; Beattie, Elizabeth; Draper, Brian; Shum, David; Thalib, Lukman; Jones, Cindy; O'Dwyer, Siobhan; Mervin, Cindy

2015-08-12

Apathy, agitated behaviours, loneliness and depression are common consequences of dementia. This trial aims to evaluate the effect of a robotic animal on behavioural and psychological symptoms of dementia in people with dementia living in long-term aged care. A cluster-randomised controlled trial with three treatment groups: PARO (robotic animal), Plush-Toy (non-robotic PARO) or Usual Care (Control). The nursing home sites are Australian Government approved and accredited facilities of 60 or more beds. The sites are located in South-East Queensland, Australia. A sample of 380 adults with a diagnosis of dementia, aged 60 years or older living in one of the participating facilities will be recruited. The intervention consists of three individual 15 min non-facilitated sessions with PARO or Plush-Toy per week, for a period of 10 weeks. The primary outcomes of interest are improvement in agitation, mood states and engagement. Secondary outcomes include sleep duration, step count, change in psychotropic medication use, change in treatment costs, and staff and family perceptions of PARO or Plush-Toy. Video data will be analysed using Noldus XT Pocket Observer; descriptive statistics will be used for participants' demographics and outcome measures; cluster and individual level analyses to test all hypotheses and Generalised Linear Models for cluster level and Generalised Estimation Equations and/or Multi-level Modeling for individual level data. The study participants or their proxy will provide written informed consent. The Griffith University Human Research Ethics Committee has approved the study (NRS/03/14/HREC). The results of the study will provide evidence of the efficacy of a robotic animal as a psychosocial treatment for the behavioural and psychological symptoms of dementia. Findings will be presented at local and international conference meetings and published in peer-reviewed journals. Australian and New Zealand Clinical Trials Registry number ACTRN

Advance care planning - a multi-centre cluster randomised clinical trial: The research protocol of the ACTION study

NARCIS (Netherlands)

J.A.C. Rietjens (Judith); I.J. Korfage (Ida); L. Dunleavy (Lesley); N.J. Preston (Nancy J.); L.J. Jabbarian (Lea J.); C.A. Christensen (Caroline Arnfeldt); M. de Brito (Maja); F. Bulli (Francesco); G. Caswell (Glenys); B. Červ (Branka); J.J.M. van Delden (Hans); L. Deliens (Luc); G. Gorini (Giuseppe); M. Groenvold (M.); D. Houttekier (Dirk); F. Ingravallo (Francesca); M.C. Kars (Marijke); U. Lunder (Urska); G. Miccinesi (Guido); A. Mimić (Alenka); E. Paci (Eugenio); S. Payne (S.); S. Polinder (Suzanne); K. Pollock (Kristian); J. Seymour (Jane); A. Simonič (Anja); A.T. Johnsen (Anna Thit); M.N. Verkissen (Mariëtte N.); E.G.E. de Vries (Elisabeth); A. Wilcock (Andrew); M. Zwakman (Marieke); A. van der Heide (Agnes)

2016-01-01

textabstractBackground: Awareness of preferences regarding medical care should be a central component of the care of patients with advanced cancer. Open communication can facilitate this but can occur in an ad hoc or variable manner. Advance care planning (ACP) is a formalized process of

Advance care planning - a multi-centre cluster randomised clinical trial : The research protocol of the ACTION study

NARCIS (Netherlands)

Rietjens, Judith A C; Korfage, Ida J.; Dunleavy, Lesley; Preston, Nancy J.; Jabbarian, Lea J.; Christensen, Caroline Arnfeldt; de Brito, Maja; Bulli, Francesco; Caswell, Glenys; Červ, Branka; van Delden, Johannes; Deliens, Luc; Gorini, Giuseppe; Groenvold, Mogens; Houttekier, Dirk; Ingravallo, Francesca; Kars, Marijke C.; Lunder, Urška; Miccinesi, Guido; Mimić, Alenka; Paci, Eugenio; Payne, Sheila; Polinder, Suzanne; Pollock, Kristian; Seymour, Jane; Simonič, Anja; Johnsen, Anna Thit; Verkissen, Mariëtte N.; de Vries, Esther; Wilcock, Andrew; Zwakman, Marieke; van der Heide (Pl), Agnes

2016-01-01

Background: Awareness of preferences regarding medical care should be a central component of the care of patients with advanced cancer. Open communication can facilitate this but can occur in an ad hoc or variable manner. Advance care planning (ACP) is a formalized process of communication between

Improving the Eco-Efficiency of High Performance Computing Clusters Using EECluster

Directory of Open Access Journals (Sweden)

Alberto Cocaña-Fernández

2016-03-01

Full Text Available As data and supercomputing centres increase their performance to improve service quality and target more ambitious challenges every day, their carbon footprint also continues to grow, and has already reached the magnitude of the aviation industry. Also, high power consumptions are building up to a remarkable bottleneck for the expansion of these infrastructures in economic terms due to the unavailability of sufficient energy sources. A substantial part of the problem is caused by current energy consumptions of High Performance Computing (HPC clusters. To alleviate this situation, we present in this work EECluster, a tool that integrates with multiple open-source Resource Management Systems to significantly reduce the carbon footprint of clusters by improving their energy efficiency. EECluster implements a dynamic power management mechanism based on Computational Intelligence techniques by learning a set of rules through multi-criteria evolutionary algorithms. This approach enables cluster operators to find the optimal balance between a reduction in the cluster energy consumptions, service quality, and number of reconfigurations. Experimental studies using both synthetic and actual workloads from a real world cluster support the adoption of this tool to reduce the carbon footprint of HPC clusters.

The Diabetes Remission Clinical Trial (DiRECT): protocol for a cluster randomised trial.

Science.gov (United States)

Leslie, Wilma S; Ford, Ian; Sattar, Naveed; Hollingsworth, Kieren G; Adamson, Ashley; Sniehotta, Falko F; McCombie, Louise; Brosnahan, Naomi; Ross, Hazel; Mathers, John C; Peters, Carl; Thom, George; Barnes, Alison; Kean, Sharon; McIlvenna, Yvonne; Rodrigues, Angela; Rehackova, Lucia; Zhyzhneuskaya, Sviatlana; Taylor, Roy; Lean, Mike E J

2016-02-16

Despite improving evidence-based practice following clinical guidelines to optimise drug therapy, Type 2 diabetes (T2DM) still exerts a devastating toll from vascular complications and premature death. Biochemical remission of T2DM has been demonstrated with weight loss around 15kg following bariatric surgery and in several small studies of non-surgical energy-restriction treatments. The non-surgical Counterweight-Plus programme, running in Primary Care where obesity and T2DM are routinely managed, produces >15 kg weight loss in 33% of all enrolled patients. The Diabetes UK-funded Counterpoint study suggested that this should be sufficient to reverse T2DM by removing ectopic fat in liver and pancreas, restoring first-phase insulin secretion. The Diabetes Remission Clinical Trial (DiRECT) was designed to determine whether a structured, intensive, weight management programme, delivered in a routine Primary Care setting, is a viable treatment for achieving durable normoglycaemia. Other aims are to understand the mechanistic basis of remission and to identify psychological predictors of response. Cluster-randomised design with GP practice as the unit of randomisation: 280 participants from around 30 practices in Scotland and England will be allocated either to continue usual guideline-based care or to add the Counterweight-Plus weight management programme, which includes primary care nurse or dietitian delivery of 12-20weeks low calorie diet replacement, food reintroduction, and long-term weight loss maintenance. Main inclusion criteria: men and women aged 20-65 years, all ethnicities, T2DM 0-6years duration, BMI 27-45 kg/m(2). Tyneside participants will undergo Magnetic Resonance (MR) studies of pancreatic and hepatic fat, and metabolic studies to determine mechanisms underlying T2DM remission. Co-primary endpoints: weight reduction ≥ 15 kg and HbA1c <48 mmol/mol at one year. Further follow-up at 2 years. This study will establish whether a structured weight

A randomised controlled trial of three or one breathing technique training sessions for breathlessness in people with malignant lung disease.

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Johnson, Miriam J; Kanaan, Mona; Richardson, Gerry; Nabb, Samantha; Torgerson, David; English, Anne; Barton, Rachael; Booth, Sara

2015-09-07

About 90 % of patients with intra-thoracic malignancy experience breathlessness. Breathing training is helpful, but it is unknown whether repeated sessions are needed. The present study aims to test whether three sessions are better than one for breathlessness in this population. This is a multi-centre randomised controlled non-blinded parallel arm trial. Participants were allocated to three sessions or single (1:2 ratio) using central computer-generated block randomisation by an independent Trials Unit and stratified for centre. The setting was respiratory, oncology or palliative care clinics at eight UK centres. Inclusion criteria were people with intrathoracic cancer and refractory breathlessness, expected prognosis ≥3 months, and no prior experience of breathing training. The trial intervention was a complex breathlessness intervention (breathing training, anxiety management, relaxation, pacing, and prioritisation) delivered over three hour-long sessions at weekly intervals, or during a single hour-long session. The main primary outcome was worst breathlessness over the previous 24 hours ('worst'), by numerical rating scale (0 = none; 10 = worst imaginable). Our primary analysis was area under the curve (AUC) 'worst' from baseline to 4 weeks. All analyses were by intention to treat. Between April 2011 and October 2013, 156 consenting participants were randomised (52 three; 104 single). Overall, the 'worst' score reduced from 6.81 (SD, 1.89) to 5.84 (2.39). Primary analysis [n = 124 (79 %)], showed no between-arm difference in the AUC: three sessions 22.86 (7.12) vs single session 22.58 (7.10); P value = 0.83); mean difference 0.2, 95 % CIs (-2.31 to 2.97). Complete case analysis showed a non-significant reduction in QALYs with three sessions (mean difference -0.006, 95 % CIs -0.018 to 0.006). Sensitivity analyses found similar results. The probability of the single session being cost-effective (threshold value of £20,000 per QALY) was over 80 %. There was no

Cognitive Rehabilitation for Attention and Memory in people with Multiple Sclerosis: study protocol for a randomised controlled trial (CRAMMS).

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Lincoln, Nadina B; das Nair, Roshan; Bradshaw, Lucy; Constantinescu, Cris S; Drummond, Avril E R; Erven, Alexandra; Evans, Amy L; Fitzsimmons, Deborah; Montgomery, Alan A; Morgan, Miriam

2015-12-08

People with multiple sclerosis have problems with memory and attention. Cognitive rehabilitation is a structured set of therapeutic activities designed to retrain an individual's memory and other cognitive functions. Cognitive rehabilitation may be provided to teach people strategies to cope with these problems, in order to reduce the impact on everyday life. The effectiveness of cognitive rehabilitation for people with multiple sclerosis has not been established. This is a multi-centre, randomised controlled trial investigating the clinical and cost-effectiveness of a group-based cognitive rehabilitation programme for attention and memory problems for people with multiple sclerosis. Four hundred people with multiple sclerosis will be randomised from at least four centres. Participants will be eligible if they have memory problems, are 18 to 69 years of age, are able to travel to attend group sessions and give informed consent. Participants will be randomised in a ratio of 6:5 to the group rehabilitation intervention plus usual care or usual care alone. Intervention groups will receive 10 weekly sessions of a manualised cognitive rehabilitation programme. The intervention will include both restitution strategies to retrain impaired attention and memory functions and compensation strategies to enable participants to cope with their cognitive problems. All participants will receive a follow-up questionnaire and an assessment by a research assistant at 6 and 12 months after randomisation. The primary outcome is the Multiple Sclerosis Impact Scale (MSIS) Psychological subscale at 12 months. Secondary outcomes include the Everyday Memory Questionnaire, General Health Questionnaire-30, EQ-5D and a service use questionnaire from participants, and the Everyday Memory Questionnaire-relative version and Carer Strain Index from a relative or friend. The primary analysis will be based on intention to treat. A mixed-model regression analysis of the MSIS Psychological

The QICKD study protocol: a cluster randomised trial to compare quality improvement interventions to lower systolic BP in chronic kidney disease (CKD in primary care

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du Bois Elizabeth

2009-07-01

Full Text Available Abstract Background Chronic kidney disease (CKD is a relatively newly recognised but common long-term condition affecting 5 to 10% of the population. Effective management of CKD, with emphasis on strict blood pressure (BP control, reduces cardiovascular risk and slows the progression of CKD. There is currently an unprecedented rise in referral to specialist renal services, which are often located in tertiary centres, inconvenient for patients, and wasteful of resources. National and international CKD guidelines include quality targets for primary care. However, there have been no rigorous evaluations of strategies to implement these guidelines. This study aims to test whether quality improvement interventions improve primary care management of elevated BP in CKD, reduce cardiovascular risk, and slow renal disease progression Design Cluster randomised controlled trial (CRT Methods This three-armed CRT compares two well-established quality improvement interventions with usual practice. The two interventions comprise: provision of clinical practice guidelines with prompts and audit-based education. The study population will be all individuals with CKD from general practices in eight localities across England. Randomisation will take place at the level of the general practices. The intended sample (three arms of 25 practices powers the study to detect a 3 mmHg difference in systolic BP between the different quality improvement interventions. An additional 10 practices per arm will receive a questionnaire to measure any change in confidence in managing CKD. Follow up will take place over two years. Outcomes will be measured using anonymised routinely collected data extracted from practice computer systems. Our primary outcome measure will be reduction of systolic BP in people with CKD and hypertension at two years. Secondary outcomes will include biomedical outcomes and markers of quality, including practitioner confidence in managing CKD. A small

Timing of intervention in high-risk non-ST-elevation acute coronary syndromes in PCI versus non-PCI centres : Sub-group analysis of the ELISA-3 trial.

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Badings, E A; Remkes, W S; Dambrink, J-H E; The, S H K; Van Wijngaarden, J; Tjeerdsma, G; Rasoul, S; Timmer, J R; van der Wielen, M L J; Lok, D J A; van 't Hof, A W J

2016-03-01

To compare the effect of timing of intervention in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) in percutaneous coronary intervention (PCI) versus non-PCI centres. A post-hoc sub-analysis was performed of the ELISA III trial, a randomised multicentre trial investigating outcome of early ( 48 h) angiography and revascularisation in 542 patients with high-risk NSTE-ACS. 90 patients were randomised in non-PCI centres and tended to benefit more from an early invasive strategy than patients included in the PCI centre (relative risk 0.23 vs. 0.85 [p for interaction = 0.089] for incidence of the combined primary endpoint of death, reinfarction and recurrent ischaemia after 30 days of follow-up). This was largely driven by reduction in recurrent ischaemia. In non-PCI centres, patients randomised to the late group had a 4 and 7 day longer period until PCI or coronary artery bypass grafting, respectively. This difference was less pronounced in the PCI centre. This post-hoc analysis from the ELISA-3 trial suggests that NSTE-ACS patients initially hospitalised in non-PCI centres show the largest benefit from early angiography and revascularisation, associated with a shorter waiting time to revascularisation. Improved patient logistics and transfer between non-PCI and PCI centres might therefore result in better clinical outcome.

Up-skilling associate clinicians in Malawi in emergency obstetric, neonatal care and clinical leadership: the ETATMBA cluster randomised controlled trial.

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Ellard, David R; Chimwaza, Wanangwa; Davies, David; Simkiss, Doug; Kamwendo, Francis; Mhango, Chisale; Quenby, Siobhan; Kandala, Ngianga-Bakwin; O'Hare, Joseph Paul

2016-01-01

The ETATMBA (Enhancing Training And Technology for Mothers and Babies in Africa) project-trained associate clinicians (ACs/clinical officers) as advanced clinical leaders in emergency obstetric and neonatal care. This trial aimed to evaluate the impact of training on obstetric health outcomes in Malawi. A cluster randomised controlled trial with 14 districts of Malawi (8 intervention, 6 control) as units of randomisation. Intervention districts housed the 46 ACs who received the training programme. The primary outcome was district (health facility-based) perinatal mortality rates. Secondary outcomes included maternal mortality ratios, neonatal mortality rate, obstetric and birth variables. The study period was 2011-2013. Mortality rates/ratios were examined using an interrupted time series (ITS) to identify trends over time. The ITS reveals an improving trend in perinatal mortality across both groups, but better in the control group (intervention, effect -3.58, SE 2.65, CI (-9.85 to 2.69), p=0.20; control, effect -17.79, SE 6.83, CI (-33.95 to -1.64), p=0.03). Maternal mortality ratios are seen to have improved in intervention districts while worsening in the control districts (intervention, effect -38.11, SE 50.30, CI (-157.06 to 80.84), p=0.47; control, effect 11.55, SE 87.72, CI (-195.87 to 218.98), p=0.90). There was a 31% drop in neonatal mortality rate in intervention districts while in control districts, the rate rises by 2%. There are no significant differences in the other secondary outcomes. This is one of the first randomised studies looking at the effect of structured training on health outcomes in this setting. Notwithstanding a number of limitations, this study suggests that up-skilling this cadre is possible, and could impact positively on health outcomes. ISRCTN63294155; Results.

Study protocol for the evaluation of an Infant Simulator based program delivered in schools: a pragmatic cluster randomised controlled trial.

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Brinkman, Sally A; Johnson, Sarah E; Lawrence, David; Codde, James P; Hart, Michael B; Straton, Judith A Y; Silburn, Sven

2010-10-21

This paper presents the study protocol for a pragmatic randomised controlled trial to evaluate the impact of a school based program developed to prevent teenage pregnancy. The program includes students taking care of an Infant Simulator; despite growing popularity and an increasing global presence of such programs, there is no published evidence of their long-term impact. The aim of this trial is to evaluate the Virtual Infant Parenting (VIP) program by investigating pre-conceptual health and risk behaviours, teen pregnancy and the resultant birth outcomes, early child health and maternal health. Fifty-seven schools (86% of 66 eligible secondary schools) in Perth, Australia were recruited to the clustered (by school) randomised trial, with even randomisation to the intervention and control arms. Between 2003 and 2006, the VIP program was administered to 1,267 participants in the intervention schools, while 1,567 participants in the non-intervention schools received standard curriculum. Participants were all female and aged between 13-15 years upon recruitment. Pre and post-intervention questionnaires measured short-term impact and participants are now being followed through their teenage years via data linkage to hospital medical records, abortion clinics and education records. Participants who have a live birth are interviewed by face-to-face interview. Kaplan-Meier survival analysis and proportional hazards regression will test for differences in pregnancy, birth and abortion rates during the teenage years between the study arms. This protocol paper provides a detailed overview of the trial design as well as initial results in the form of participant flow. The authors describe the intervention and its delivery within the natural school setting and discuss the practical issues in the conduct of the trial, including recruitment. The trial is pragmatic and will directly inform those who provide Infant Simulator based programs in school settings. ISRCTN24952438.

Effects of a free school breakfast programme on school attendance, achievement, psychosocial function, and nutrition: a stepped wedge cluster randomised trial.

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Ni Mhurchu, Cliona; Turley, Maria; Gorton, Delvina; Jiang, Yannan; Michie, Jo; Maddison, Ralph; Hattie, John

2010-11-29

Approximately 55,000 children in New Zealand do not eat breakfast on any given day. Regular breakfast skipping has been associated with poor diets, higher body mass index, and adverse effects on children's behaviour and academic performance. Research suggests that regular breakfast consumption can improve academic performance, nutrition and behaviour. This paper describes the protocol for a stepped wedge cluster randomised trial of a free school breakfast programme. The aim of the trial is to determine the effects of the breakfast intervention on school attendance, achievement, psychosocial function, dietary habits and food security. Sixteen primary schools in the North Island of New Zealand will be randomised in a sequential stepped wedge design to a free before-school breakfast programme consisting of non-sugar coated breakfast cereal, milk products, and/or toast and spreads. Four hundred children aged 5-13 years (approximately 25 per school) will be recruited. Data collection will be undertaken once each school term over the 2010 school year (February to December). The primary trial outcome is school attendance, defined as the proportion of students achieving an attendance rate of 95% or higher. Secondary outcomes are academic achievement (literacy, numeracy, self-reported grades), sense of belonging at school, psychosocial function, dietary habits, and food security. A concurrent process evaluation seeks information on parents', schools' and providers' perspectives of the breakfast programme. This randomised controlled trial will provide robust evidence of the effects of a school breakfast programme on students' attendance, achievement and nutrition. Furthermore the study provides an excellent example of the feasibility and value of the stepped wedge trial design in evaluating pragmatic public health intervention programmes. Australian New Zealand Clinical Trials Registry (ANZCTR) - ACTRN12609000854235.

Feasibility and efficacy of a multi-factorial intervention to prevent falls in older adults with cognitive impairment living in residential care (ProF-Cog). A feasibility and pilot cluster randomised controlled trial.

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Whitney, Julie; Jackson, Stephen H D; Martin, Finbarr C

2017-05-30

Falls are common in people with dementia living in residential care. The ProF-Cog intervention was developed to address fall risk factors specific to this population. The aim of this study was to evaluate the safety, acceptability, and feasibility of the intervention and provide an estimate of its efficacy. This was a cluster randomised controlled pilot study undertaken in care homes in London, UK. All permanent residents living in participating homes who were not terminally ill were invited to participate. The intervention included an assessment of falls risk factors followed by a tailored intervention which could include dementia care mapping, comprehensive geriatric assessment, occupational therapy input and twice-weekly exercise for 6 months as required to target identified risk factors. The control group received usual care without a falls risk assessment. Standing balance was the primary outcome. This and other outcome measures were collected at baseline and after 6 months. Falls were recorded for this period using incident reports. Changes were analysed using multi-level modelling. Adherence to the interventions, adverse events and trial feasibility were recorded. Nine care homes enrolled in the study with a total 191 participants (51% of those eligible); five homes allocated to the intervention with 103 participants, and four homes to the usual care control group with 88 participants. The intervention was safe with only one reported fall whilst undertaking exercise. Adherence to agreed recommendations on activity and the environment was modest (21 and 45% respectively) and to exercise was poor (41%). Balance scores (score range 0-49) analysed on 100 participants decreased by a mean of 3.9 in the control and 5.1 in the intervention groups, a non-significant difference (p = 0.9). In other measures, both groups declined equally and there was no difference in falls rates (IRR = 1.59 95%, CI 0.67-3.76). The intervention was safe but not clinically

Multi-criteria correlation of tephra deposits to source centres applied in the Auckland Volcanic Field, New Zealand

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Hopkins, Jenni L.; Wilson, Colin J. N.; Millet, Marc-Alban; Leonard, Graham S.; Timm, Christian; McGee, Lucy E.; Smith, Ian E. M.; Smith, Euan G. C.

2017-07-01

Linking tephras back to their source centre(s) in volcanic fields is crucial not only to reconstruct the eruptive history of the volcanic field but also to understand tephra dispersal patterns and thus the potential hazards posed by a future eruption. Here we present a multi-disciplinary approach to correlate distal basaltic tephra deposits from the Auckland Volcanic Field (AVF) to their source centres using proximal whole-rock geochemical signatures. In order to achieve these correlations, major and trace element tephra-derived glass compositions are compared with published and newly obtained whole-rock geochemical data for the entire field. The results show that incompatible trace element ratios (e.g. (Gd/Yb)N, (La/Yb)N, (Zr/Yb)N) vary widely across the AVF (e.g. (La/Yb)N = 5 to 40) but show a more restricted range within samples from a single volcanic centre (e.g. (La/Yb)N = 5 to 10). These ratios are also the least affected by fractional crystallisation and are therefore the most appropriate geochemical tools for correlation between tephra and whole-rock samples. However, findings for the AVF suggest that each volcanic centre does not have a unique geochemical signature in the field as a whole, thus preventing unambiguous correlation of tephras to source centre using geochemistry alone. A number of additional criteria are therefore combined to further constrain the source centres of the distal tephras including age, eruption scale, and location (of centres, and sites where tephra were sampled). The combination of tephrostratigraphy, 40Ar/39Ar dating and morphostratigraphic constraints allow, for the first time, the relative and absolute ordering of 48 of 53 volcanic centres of the Auckland Volcanic Field to be resolved. Eruption frequencies are shown to vary between 0.13 and 1.5 eruptions/kyr and repose periods between individual eruptions vary from <0.1 to 13 kyr, with 23 of the 48 centres shown to have pre-eruptive repose periods of <1000 years. No spatial

Protocol for a feasibility cluster randomised controlled trial of a peer-led school-based intervention to increase the physical activity of adolescent girls (PLAN-A).

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Sebire, Simon J; Edwards, Mark J; Campbell, Rona; Jago, Russell; Kipping, Ruth; Banfield, Kathryn; Tomkinson, Keeley; Garfield, Kirsty; Lyons, Ronan A; Simon, Joanne; Blair, Peter S; Hollingworth, William

2016-01-01

Physical activity levels are low amongst adolescent girls, and this population faces specific barriers to being active. Peer influences on health behaviours are important in adolescence and peer-led interventions might hold promise to change behaviour. This paper describes the protocol for a feasibility cluster randomised controlled trial of Peer-Led physical Activity iNtervention for Adolescent girls (PLAN-A), a peer-led intervention aimed at increasing adolescent girls' physical activity levels. A two-arm cluster randomised feasibility trial will be conducted in six secondary schools (intervention n  = 4; control n  = 2) with year 8 (12-13 years old) girls. The intervention will operate at a year group level and consist of year 8 girls nominating influential peers within their year group to become peer-supporters. Approximately 15 % of the cohort will receive 3 days of training about physical activity and interpersonal communication skills. Peer-supporters will then informally diffuse messages about physical activity amongst their friends for 10 weeks. Data will be collected at baseline (time 0 (T0)), immediately after the intervention (time 1 (T1)) and 12 months after baseline measures (time 2 (T2)). In this feasibility trial, the primary interest is in the recruitment of schools and participants (both year 8 girls and peer-supporters), delivery and receipt of the intervention, data provision rates and identifying the cost categories for future economic analysis. Physical activity will be assessed using 7-day accelerometry, with the likely primary outcome in a fully-powered trial being daily minutes of moderate-to-vigorous physical activity. Participants will also complete psychosocial questionnaires at each time point: assessing motivation, self-esteem and peer physical activity norms. Data analysis will be largely descriptive and focus on recruitment, attendance and data provision rates. The findings will inform the sample size required for a

Multi-party Measurement-Device-Independent Quantum Key Distribution Based on Cluster States

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Liu, Chuanqi; Zhu, Changhua; Ma, Shuquan; Pei, Changxing

2018-03-01

We propose a novel multi-party measurement-device-independent quantum key distribution (MDI-QKD) protocol based on cluster states. A four-photon analyzer which can distinguish all the 16 cluster states serves as the measurement device for four-party MDI-QKD. Any two out of four participants can build secure keys after the analyzers obtains successful outputs and the two participants perform post-processing. We derive a security analysis for the protocol, and analyze the key rates under different values of polarization misalignment. The results show that four-party MDI-QKD is feasible over 280 km in the optical fiber channel when the key rate is about 10- 6 with the polarization misalignment parameter 0.015. Moreover, our work takes an important step toward a quantum communication network.

A randomised controlled trial evaluating family mediated exercise (FAME therapy following stroke

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Stokes Emma

2008-06-01

Full Text Available Abstract Background Stroke is a leading cause of disability among adults worldwide. Evidence suggests that increased duration of exercise therapy following stroke has a positive impact on functional outcome following stroke. The main objective of this randomised controlled trial is to evaluate the impact of additional family assisted exercise therapy in people with acute stroke. Methods/Design A prospective multi-centre single blind randomised controlled trial will be conducted. Forty patients with acute stroke will be randomised into either an experimental or control group. The experimental group will receive routine therapy and additional lower limb exercise therapy in the form of family assisted exercises. The control group will receive routine therapy with no additional formal input from their family members. Participants will be assessed at baseline, post intervention and followed up at three months using a series of standardised outcome measures. A secondary aim of the project is to evaluate the impact of the family mediated exercise programme on the person with stroke and the individual(s assisting in the delivery of exercises using a qualitative methodology. The study has gained ethical approval from the Research Ethics Committees of each of the clinical sites involved in the study. Discussion This study will evaluate a structured programme of exercises that can be delivered to people with stroke by their 'family members/friends'. Given that the progressive increase in the population of older people is likely to lead to an increased prevalence of stroke in the future, it is important to reduce the burden of this illness on the individual, the family and society. Family mediated exercises can maximise the carry over outside formal physiotherapy sessions, giving patients the opportunity for informal practice. Trial Registration The protocol for this study is registered with the US NIH Clinical trials registry (NCT00666744

Development of on-chip multi-imaging flow cytometry for identification of imaging biomarkers of clustered circulating tumor cells.

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Hyonchol Kim

Full Text Available An on-chip multi-imaging flow cytometry system has been developed to obtain morphometric parameters of cell clusters such as cell number, perimeter, total cross-sectional area, number of nuclei and size of clusters as "imaging biomarkers", with simultaneous acquisition and analysis of both bright-field (BF and fluorescent (FL images at 200 frames per second (fps; by using this system, we examined the effectiveness of using imaging biomarkers for the identification of clustered circulating tumor cells (CTCs. Sample blood of rats in which a prostate cancer cell line (MAT-LyLu had been pre-implanted was applied to a microchannel on a disposable microchip after staining the nuclei using fluorescent dye for their visualization, and the acquired images were measured and compared with those of healthy rats. In terms of the results, clustered cells having (1 cell area larger than 200 µm2 and (2 nucleus area larger than 90 µm2 were specifically observed in cancer cell-implanted blood, but were not observed in healthy rats. In addition, (3 clusters having more than 3 nuclei were specific for cancer-implanted blood and (4 a ratio between the actual perimeter and the perimeter calculated from the obtained area, which reflects a shape distorted from ideal roundness, of less than 0.90 was specific for all clusters having more than 3 nuclei and was also specific for cancer-implanted blood. The collected clusters larger than 300 µm2 were examined by quantitative gene copy number assay, and were identified as being CTCs. These results indicate the usefulness of the imaging biomarkers for characterizing clusters, and all of the four examined imaging biomarkers-cluster area, nuclei area, nuclei number, and ratio of perimeter-can identify clustered CTCs in blood with the same level of preciseness using multi-imaging cytometry.

IntroductionThe Cluster mission

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M. Fehringer

Full Text Available The Cluster mission, ESA’s first cornerstone project, together with the SOHO mission, dating back to the first proposals in 1982, was finally launched in the summer of 2000. On 16 July and 9 August, respectively, two Russian Soyuz rockets blasted off from the Russian cosmodrome in Baikonour to deliver two Cluster spacecraft, each into their proper orbit. By the end of August 2000, the four Cluster satellites had reached their final tetrahedral constellation. The commissioning of 44 instruments, both individually and as an ensemble of complementary tools, was completed five months later to ensure the optimal use of their combined observational potential. On 1 February 2001, the mission was declared operational. The main goal of the Cluster mission is to study the small-scale plasma structures in three dimensions in key plasma regions, such as the solar wind, bow shock, magnetopause, polar cusps, magnetotail and the auroral zones. With its unique capabilities of three-dimensional spatial resolution, Cluster plays a major role in the International Solar Terrestrial Program (ISTP, where Cluster and the Solar and Heliospheric Observatory (SOHO are the European contributions. Cluster’s payload consists of state-of-the-art plasma instrumentation to measure electric and magnetic fields from the quasi-static up to high frequencies, and electron and ion distribution functions from energies of nearly 0 eV to a few MeV. The science operations are coordinated by the Joint Science Operations Centre (JSOC, at the Rutherford Appleton Laboratory (UK, and implemented by the European Space Operations Centre (ESOC, in Darmstadt, Germany. A network of eight national data centres has been set up for raw data processing, for the production of physical parameters, and their distribution to end users all over the world. The latest information on the Cluster mission can be found at http://sci.esa.int/cluster/.

IntroductionThe Cluster mission

Directory of Open Access Journals (Sweden)

C. P. Escoubet

2001-09-01

Full Text Available The Cluster mission, ESA’s first cornerstone project, together with the SOHO mission, dating back to the first proposals in 1982, was finally launched in the summer of 2000. On 16 July and 9 August, respectively, two Russian Soyuz rockets blasted off from the Russian cosmodrome in Baikonour to deliver two Cluster spacecraft, each into their proper orbit. By the end of August 2000, the four Cluster satellites had reached their final tetrahedral constellation. The commissioning of 44 instruments, both individually and as an ensemble of complementary tools, was completed five months later to ensure the optimal use of their combined observational potential. On 1 February 2001, the mission was declared operational. The main goal of the Cluster mission is to study the small-scale plasma structures in three dimensions in key plasma regions, such as the solar wind, bow shock, magnetopause, polar cusps, magnetotail and the auroral zones. With its unique capabilities of three-dimensional spatial resolution, Cluster plays a major role in the International Solar Terrestrial Program (ISTP, where Cluster and the Solar and Heliospheric Observatory (SOHO are the European contributions. Cluster’s payload consists of state-of-the-art plasma instrumentation to measure electric and magnetic fields from the quasi-static up to high frequencies, and electron and ion distribution functions from energies of nearly 0 eV to a few MeV. The science operations are coordinated by the Joint Science Operations Centre (JSOC, at the Rutherford Appleton Laboratory (UK, and implemented by the European Space Operations Centre (ESOC, in Darmstadt, Germany. A network of eight national data centres has been set up for raw data processing, for the production of physical parameters, and their distribution to end users all over the world. The latest information on the Cluster mission can be found at http://sci.esa.int/cluster/.

An exploratory cluster randomised trial of a university halls of residence based social norms marketing campaign to reduce alcohol consumption among 1st year students.

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Moore, Graham F; Williams, Annie; Moore, Laurence; Murphy, Simon

2013-04-18

This exploratory trial examines the feasibility of implementing a social norms marketing campaign to reduce student drinking in universities in Wales, and evaluating it using cluster randomised trial methodology. Fifty residence halls in 4 universities in Wales were randomly assigned to intervention or control arms. Web and paper surveys were distributed to students within these halls (n = 3800), assessing exposure/contamination, recall of and evaluative responses to intervention messages, perceived drinking norms and personal drinking behaviour. Measures included the Drinking Norms Rating Form, the Daily Drinking Questionnaire and AUDIT-C. A response rate of 15% (n = 554) was achieved, varying substantially between sites. Intervention posters were seen by 80% and 43% of students in intervention and control halls respectively, with most remaining materials seen by a minority in both groups. Intervention messages were rated as credible and relevant by little more than half of students, though fewer felt they would influence their behaviour, with lighter drinkers more likely to perceive messages as credible. No differences in perceived norms were observed between intervention and control groups. Students reporting having seen intervention materials reported lower descriptive and injunctive norms than those who did not. Attention is needed to enhancing exposure, credibility and perceived relevance of intervention messages, particularly among heavier drinkers, before definitive evaluation can be recommended. A definitive evaluation would need to consider how it would achieve sufficient response rates, whilst hall-level cluster randomisation appears subject to a significant degree of contamination. ISRCTN: ISRCTN48556384.

A randomised trial of preoperative radiotherapy for stage T3 adenocarcinoma of rectum (TROG 01.04): a progress report

International Nuclear Information System (INIS)

Ngan, S.; Fisher, R.; McKay, M.J.; McClure, B.; Burmeister, B.H.; Schache, D.; Joseph, D.; Solomon, M.; Ackland, S.P.; Goldstein, D.; McLachlan, S.; Dhillon, H.; Thompson, P.

2003-01-01

To provide a progress report of the conduct of the randomised trial TROG 01.04. This is a randomised Australian and New Zealand multi-centre trial of preoperative radiotherapy for rectal cancer currently being conducted under the auspices of Trans-Tasman Radiation Oncology Group, Australasian Gastrointestinal Trials Group, Colorectal Surgical Society of Australasia, and Royal Australasian College of Surgeons. The trial comprises two studies, each with its own main objective. These objectives are, in patients with T3 clinically resectable carcinoma of the rectum, to demonstrate that (Study 1) the local recurrence rate in patients treated with a long course (LC) of pre-operative radiotherapy with continuous infusion 5-FU is lower than that in patients treated with a short course (SC) of pre-operative radiotherapy with early surgery; and (Study 2) the local recurrence rate in patients given pre-operative radiotherapy and chemotherapy is lower than that in patients treated with initial surgery. Over 150 patients have been accrued from 21 centres in the first 21 months. All patients were enrolled on Study 1, SC versus LC pre-operative radiotherapy. Study 2 has enrolled no patients in 15 months and has been discontinued. There was no obvious difference in rates of serious adverse events of SC and LC. An Independent Data Monitoring Committee is monitoring these and other aspects of the trial. The trial of SC versus LC is progressing well: such a trial is clearly feasible in Australia and New Zealand. It is however not feasible to compare initial surgery with preoperative radiotherapy

Action to Support Practices Implement Research Evidence (ASPIRE): protocol for a cluster-randomised evaluation of adaptable implementation packages targeting 'high impact' clinical practice recommendations in general practice.

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Willis, Thomas A; Hartley, Suzanne; Glidewell, Liz; Farrin, Amanda J; Lawton, Rebecca; McEachan, Rosemary R C; Ingleson, Emma; Heudtlass, Peter; Collinson, Michelle; Clamp, Susan; Hunter, Cheryl; Ward, Vicky; Hulme, Claire; Meads, David; Bregantini, Daniele; Carder, Paul; Foy, Robbie

2016-02-29

There are recognised gaps between evidence and practice in general practice, a setting which provides particular challenges for implementation. We earlier screened clinical guideline recommendations to derive a set of 'high impact' indicators based upon criteria including potential for significant patient benefit, scope for improved practice and amenability to measurement using routinely collected data. We aim to evaluate the effectiveness and cost-effectiveness of a multifaceted, adaptable intervention package to implement four targeted, high impact recommendations in general practice. The research programme Action to Support Practice Implement Research Evidence (ASPIRE) includes a pair of pragmatic cluster-randomised trials which use a balanced incomplete block design. Clusters are general practices in West Yorkshire, United Kingdom (UK), recruited using an 'opt-out' recruitment process. The intervention package adapted to each recommendation includes combinations of audit and feedback, educational outreach visits and computerised prompts with embedded behaviour change techniques selected on the basis of identified needs and barriers to change. In trial 1, practices are randomised to adapted interventions targeting either diabetes control or risky prescribing and those in trial 2 to adapted interventions targeting either blood pressure control in patients at risk of cardiovascular events or anticoagulation in atrial fibrillation. The respective primary endpoints comprise achievement of all recommended target levels of haemoglobin A1c (HbA1c), blood pressure and cholesterol in patients with type 2 diabetes, a composite indicator of risky prescribing, achievement of recommended blood pressure targets for specific patient groups and anticoagulation prescribing in patients with atrial fibrillation. We are also randomising practices to a fifth, non-intervention control group to further assess Hawthorne effects. Outcomes will be assessed using routinely collected data

Effect of a mass radio campaign on family behaviours and child survival in Burkina Faso: a repeated cross-sectional, cluster-randomised trial

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Sophie Sarrassat, PhD

2018-03-01

Full Text Available Summary: Background: Media campaigns can potentially reach a large audience at relatively low cost but, to our knowledge, no randomised controlled trials have assessed their effect on a health outcome in a low-income country. We aimed to assess the effect of a radio campaign addressing family behaviours on all-cause post-neonatal under-5 child mortality in rural Burkina Faso. Methods: In this repeated cross-sectional, cluster randomised trial, clusters (distinct geographical areas in rural Burkina Faso with at least 40 000 inhabitants were selected by Development Media International based on their high radio listenership (>60% of women listening to the radio in the past week and minimum distances between radio stations to exclude population-level contamination. Clusters were randomly allocated to receive the intervention (a comprehensive radio campaign or control group (no radio media campaign. Household surveys were performed at baseline (from December, 2011, to February, 2012, midline (in November, 2013, and after 20 months of campaigning, and endline (from November, 2014, to March, 2015, after 32 months of campaigning. Primary analyses were done on an intention-to-treat basis, based on cluster-level summaries and adjusted for imbalances between groups at baseline. The primary outcome was all-cause post-neonatal under-5 child mortality. The trial was designed to detect a 20% reduction in the primary outcome with a power of 80%. Routine data from health facilities were also analysed for evidence of changes in use and these data had high statistical power. The indicators measured were new antenatal care attendances, facility deliveries, and under-5 consultations. This trial is registered with ClinicalTrial.gov, number NCT01517230. Findings: The intervention ran from March, 2012, to January, 2015. 14 clusters were selected and randomly assigned to the intervention group (n=7 or the control group (n=7. The average number of villages included per

Analytical modeling of multi-layered printed circuit board using multi-stacked via clusters as component heat spreader

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Monier-Vinard Eric

2016-01-01

Full Text Available In order to help the electronic designer to early determine the limits of the power dissipation of electronic component, an analytical model was established to allow a fast insight of relevant design parameters of a multi-layered electronic board constitution. The proposed steady-state approach based on Fourier series method promotes a practical solution to quickly investigate the potential gain of multi-layered thermal via clusters. Generally, it has been shown a good agreement between the results obtained by the proposed analytical model and those given by electronics cooling software widely used in industry. Some results highlight the fact that the conventional practices for Printed Circuit Board modeling can be dramatically underestimate source temperatures, in particular with smaller sources. Moreover, the analytic solution could be applied to optimize the heat spreading in the board structure with a local modification of the effective thermal conductivity layers.

A randomised, controlled trial of circumpatellar electrocautery in total knee replacement without patellar resurfacing

NARCIS (Netherlands)

Jonbergen, H.P. van; Scholtes, V.A.; Kampen, A. van; Poolman, R.W.

2011-01-01

The efficacy of circumpatellar electrocautery in reducing the incidence of post-operative anterior knee pain is unknown. We conducted a single-centre, outcome-assessor and patient-blinded, parallel-group, randomised, controlled trial to compare circumpatellar electrocautery with no electrocautery in

Variational treatment of the centre-of-mass motion

International Nuclear Information System (INIS)

Cornelissens, T.

1986-01-01

The weightfunction in Lipkin's general expression for eliminating the centre-of-mass coordinate from nuclear wavefunctions has been approximated by a gaussian function exp (-lambdaR 2 ) with one parameter lambda to be determined by a variational calculation. This variational calculation has been carried out for the ground state of 6 Li, first using a wavefunction with different oscillator parameters for the s and p nucleons, second using oscillator functions which are also axially deformed. In both cases the centre-of-mass treatment leads to a remarkable energy gain. The lowest energies are obtained for a negative value of lambda. This surprising result can be explained on the basis of a cluster model for the internal wavefunction of 6 Li : the negative value of lambda increases the separation between the alpha and deuteron cluster. As a further test for our centre-of-mass corrected internal wavefunctions we have calculated the charge formfactor of 6 Li. At low momentum transfer we obtain an excellent agreement with the experimental results. At higher momentum transfers we obtain a diffraction dip, but not yet at the right position and height. Finally we have compared our results for the ground state energy with different cluster model results in the literature. We can conclude that, even without using a generator coordinate method, our centre-of-mass corrected wavefunctions lead to equally good results as the most sophisticated cluster models

The effect of changing movement and posture using motion-sensor biofeedback, versus guidelines-based care, on the clinical outcomes of people with sub-acute or chronic low back pain-a multicentre, cluster-randomised, placebo-controlled, pilot trial

DEFF Research Database (Denmark)

Kent, Peter; Laird, Robert; Haines, Terry

2015-01-01

sample size calculations for a fully powered trial. METHODS: A multicentre (8 clinics), cluster-randomised, placebo-controlled pilot trial compared two groups of patients seeking medical or physiotherapy primary care for sub-acute and chronic back pain. It was powered for longitudinal analysis...

Vorinostat in refractory soft tissue sarcomas - Results of a multi-centre phase II trial of the German Soft Tissue Sarcoma and Bone Tumour Working Group (AIO).

Science.gov (United States)

Schmitt, Thomas; Mayer-Steinacker, Regine; Mayer, Frank; Grünwald, Viktor; Schütte, Jochen; Hartmann, Jörg T; Kasper, Bernd; Hüsing, Johannes; Hajda, Jacek; Ottawa, Gregor; Mechtersheimer, Gunhild; Mikus, Gerd; Burhenne, Jürgen; Lehmann, Lorenz; Heilig, Christoph E; Ho, Anthony D; Egerer, Gerlinde

2016-09-01

New treatment options for patients with metastatic Soft Tissue Sarcoma are urgently needed. Preclinical studies suggested activity of vorinostat, a histone deacetylase inhibitor. A multi-centre, open-label, non-randomised phase II trial to investigate the efficacy and safety of vorinostat in patients with locally advanced or metastatic Soft Tissue Sarcoma failing 1st-line anthracycline-based chemotherapy was initiated. Patients were treated with vorinostat 400 mg po qd for 28 d followed by a treatment-free period of 7 d, representing a treatment cycle of 5 weeks. Restaging was performed every three cycles or at clinical progression. Between 06/10 and 09/13, 40 Soft Tissue Sarcoma patients were treated with vorinostat at seven participating centres. Patients had received 1 (n=8, 20%), 2 (n=10, 25%) or ≥3 (n=22, 55%) previous lines of chemotherapy. Best response after three cycles of treatment was stable disease (n=9, 23%). Median progression-free survival and overall survival were 3.2 and 12.3 months, respectively. Six patients showed long-lasting disease stabilisation for up to ten cycles. Statistical analyses failed to identify baseline predictive markers in this subgroup. Major toxicities (grade ≥III) included haematological toxicity (n=6, 15%) gastrointestinal disorders (n=5, 13%), fatigue (n=4, 10%), musculoskeletal pain (n=4, 10%), and pneumonia (n=2, 5%). In a heavily pre-treated patient population, objective response to vorinostat was low. However, a small subgroup of patients had long-lasting disease stabilisation. Further studies aiming to identify predictive markers for treatment response as well as exploration of combination regimens are warranted. NCT00918489 (ClinicalTrials.gov) EudraCT-number: 2008-008513-19. Copyright © 2016 Elsevier Ltd. All rights reserved.

Psychological rehabilitation after myocardial infarction: multicentre randomised controlled trial.

OpenAIRE

Jones, D. A.; West, R. R.

1996-01-01

OBJECTIVE: To evaluate rehabilitation after myocardial infarction. DESIGN: Randomised controlled trial of rehabilitation in unselected myocardial infarction patients in six centres, baseline data being collected on admission and by structured interview (of patients and spouses) shortly after discharge and outcome being assessed by structured interview at six months and clinical examination at 12 months. SETTING: Six district general hospitals. SUBJECTS: All 2328 eligible patients admitted ove...

Social marketing and community mobilisation to reduce underage alcohol consumption in Australia: A cluster randomised community trial.

Science.gov (United States)

Rowland, Bosco Charles; Williams, Joanne; Smith, Rachel; Hall, Jessica Kate; Osborn, Amber; Kremer, Peter; Kelly, Adrian B; Leslie, Eva; Patton, George; Mohebbi, Mohammadreza; Toumbourou, John W

2018-08-01

In many countries adolescent alcohol use is a major health problem. To supplement national policies, it is important to trial community interventions as a potential strategy to prevent adolescent alcohol use. This study evaluated a multicomponent community intervention that included community mobilisation, social marketing, and the monitoring of alcohol sales to minors. Evaluation was a clustered randomised trial design with 14 intervention and 14 control communities. Prior to randomisation, communities were matched on socioeconomic status and location. Intervention communities were not blinded. 3545 Year 8 students (M = 12 years) were surveyed at baseline from 75 schools; 3377 students were surveyed post intervention in 2013 from 54 schools. It was hypothesised that the primary outcome, individual alcohol consumption in last 30 days, after the intervention would be 15% lower in intervention communities. Secondary outcomes were consumption in the past year and intention not to drink before age 18. The intervention communities showed larger relative reductions compared to the controls in last 30-day consumption and past year (10%), but not significantly different. A significantly lower proportion of participants in the intervention community (63%), compared to the controls (71%), reported intending to drink before 18 years old. Subgroup analysis identified regional and state differences for some secondary measures. Intervention assignment was associated with lower adolescent intention to drink before the age of 18. However, more intensive and longer-term intervention may be required to measure significant differences in behaviour change. ACTRN12612000384853. Rowland B, Toumbourou JW, Osborn A, et al. BMJ Open 2013;3:e002423. doi:10.1136/bmjopen-2012-002423. Copyright © 2018 Elsevier Inc. All rights reserved.

Local wavelet correlation: applicationto timing analysis of multi-satellite CLUSTER data

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J. Soucek

2004-12-01

Full Text Available Multi-spacecraft space observations, such as those of CLUSTER, can be used to infer information about local plasma structures by exploiting the timing differences between subsequent encounters of these structures by individual satellites. We introduce a novel wavelet-based technique, the Local Wavelet Correlation (LWC, which allows one to match the corresponding signatures of large-scale structures in the data from multiple spacecraft and determine the relative time shifts between the crossings. The LWC is especially suitable for analysis of strongly non-stationary time series, where it enables one to estimate the time lags in a more robust and systematic way than ordinary cross-correlation techniques. The technique, together with its properties and some examples of its application to timing analysis of bow shock and magnetopause crossing observed by CLUSTER, are presented. We also compare the performance and reliability of the technique with classical discontinuity analysis methods. Key words. Radio science (signal processing – Space plasma physics (discontinuities; instruments and techniques

Floor heating in the multi-functional centre `Gelderhorst` in Ede, Netherlands; De Gelderhorst slaat bouwfase over

Energy Technology Data Exchange (ETDEWEB)

Wondergem, J. [Wondergem Intermedium, Weesp (Netherlands)

1997-11-01

The Gelderhorst is a multi-functional centre for elderly, deaf people. Building systems are installed normally after the rough building structure is finished. In the building process of Gelderhorst the floor heating is installed in a pre-phase of the construction of the building. Thereto, the cooperation between the installation company, the manufacturer, the wholesale business and the contractor had to be well planned. Also, problems had to be solved with respect to the choice of building materials and installation techniques. 4 ills.

Effects of the daily consumption of protein enriched bread and protein enriched drinking yoghurt on the total protein intake in older adults in a rehabilitation centre: a single blind randomised controlled trial.

Science.gov (United States)

van Til, A J; Naumann, E; Cox-Claessens, I J H M; Kremer, S; Boelsma, E; de van der Schueren, M A E

2015-05-01

To investigate the effects of protein enriched bread and drinking yoghurt, substituting regular products, on the total protein intake and the distribution of protein intake over the day in older adults. A single blind randomised controlled trial. Rehabilitation centre. Older adults (≥ 55 years) admitted to a rehabilitation centre after hospital discharge (n=34). Participants received a high protein diet (protein enriched bread and protein enriched drinking yoghurt; n=17) or a regular diet (regular bread and regular drinking yoghurt; n=17) for three consecutive weeks. Total protein intake and protein intake per meal, measured twice weekly over a three weeks period (six measurements per participant). Compared with controls, patients who received the protein enriched products had a significantly higher protein intake (115.3 g/d vs 72.5 g/d, Pconsumption of protein enriched products improves protein distribution over the day.

Targeted full energy and protein delivery in critically ill patients: a study protocol for a pilot randomised control trial (FEED Trial

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Kate Fetterplace

2018-02-01

Full Text Available Abstract Background Current guidelines for the provision of protein for critically ill patients are based on incomplete evidence, due to limited data from randomised controlled trials. The present pilot randomised controlled trial is part of a program of work to expand knowledge about the clinical effects of protein delivery to critically ill patients. The primary aim of this pilot study is to determine whether an enteral feeding protocol using a volume target, with additional protein supplementation, delivers a greater amount of protein and energy to mechanically ventilated critically ill patients than a standard nutrition protocol. The secondary aims are to evaluate the potential effects of this feeding strategy on muscle mass and other patient-centred outcomes. Methods This prospective, single-centred, pilot, randomised control trial will include 60 participants who are mechanically ventilated and can be enterally fed. Following informed consent, the participants receiving enteral nutrition in the intensive care unit (ICU will be allocated using a randomisation algorithm in a 1:1 ratio to the intervention (high-protein daily volume-based feeding protocol, providing 25 kcal/kg and 1.5 g/kg protein or standard care (hourly rate-based feeding protocol providing 25 kcal/kg and 1 g/kg protein. The co-primary outcomes are the average daily protein and energy delivered to the end of day 15 following randomisation. The secondary outcomes include change in quadriceps muscle layer thickness (QMLT from baseline (prior to randomisation to ICU discharge and other nutritional and patient-centred outcomes. Discussion This trial aims to examine whether a volume-based feeding protocol with supplemental protein increases protein and energy delivery. The potential effect of such increases on muscle mass loss will be explored. These outcomes will assist in formulating larger randomised control trials to assess mortality and morbidity. Trial registration

Insecticide-treated nets for the prevention of malaria in pregnancy: a systematic review of randomised controlled trials.

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Carol Gamble

2007-03-01

Full Text Available BACKGROUND: Protection from malaria with insecticide-treated bednets (ITNs during pregnancy is widely advocated, but evidence of benefit has been inconsistent. We undertook a systematic review of randomised trials. METHODS AND FINDINGS: Three cluster-randomised and two individually randomised trials met the inclusion criteria; four from Africa (n = 6,418 and one from Thailand (n = 223. In Africa, ITNs compared to no nets increased mean birth weight by 55 g (95% confidence interval [CI] 21-88, reduced low birth weight by 23% (relative risk [RR] 0.77, 95% CI 0.61-0.98, and reduced miscarriages/stillbirths by 33% (RR 0.67, 0.47-0.97 in the first few pregnancies. Placental parasitaemia was reduced by 23% in all gravidae (RR 0.77, 0.66-0.90. The effects were apparent in the cluster-randomised trials and the one individually randomised trial in Africa. The trial in Thailand, which randomised individuals to ITNs or untreated nets, showed reductions in anaemia and fetal loss in all gravidae, but not reductions in clinical malaria or low birth weight. CONCLUSIONS: ITNs used throughout pregnancy or from mid-pregnancy onwards have a beneficial impact on pregnancy outcome in malaria-endemic Africa in the first few pregnancies. The potential impact of ITNs in pregnant women and their newborns in malaria regions outside Africa requires further research.

BTS randomised feasibility study of active symptom control with or without chemotherapy in malignant pleural mesothelioma: ISRCTN 54469112.

Science.gov (United States)

Muers, M F; Rudd, R M; O'Brien, M E R; Qian, W; Hodson, A; Parmar, M K B; Girling, D J

2004-02-01

The incidence of mesothelioma is rising rapidly in the UK. There is no generally accepted standard treatment. The BTS recommends active symptom control (ASC). It is not known whether chemotherapy in addition prolongs survival or provides worthwhile palliation with acceptable toxicity. Palliation as recorded by patients has been fully reported for only two regimens: mitomycin, vinblastine, and cisplatin (MVP), and vinorelbine (N). The BTS and collaborators planned to conduct a phase III randomised trial comparing ASC only, ASC+MVP, and ASC+N in 840 patients with survival as the primary outcome measure. The aim of the present study was to assess the acceptability of the trial design to patients and the suitability of two standard quality of life (QL) questionnaires for mesothelioma. Collaborating centres registered all new patients with mesothelioma. Those eligible and giving informed consent completed EORTC QLQ-C30+LC13 and FACT-L QL questionnaires and were randomised between all three or any two of (1) ASC only, (2) ASC+4 cycles of MVP, and (3) ASC+12 weekly doses of N. During 1 year, 242 patients were registered of whom 109 (45%) were randomised (55% of the 197 eligible patients). Fifty two patients from 20 centres were randomised to an option including ASC only. This translates into a rate of 312 per year from 60 centres interested in collaborating in the phase III trial. The EORTC QL questionnaire was superior to FACT-L in terms of completeness of data and patient preference. Clinically relevant palliation was achieved with ASC. The planned phase III trial is feasible.

A randomised, feasibility trial of a tele-health intervention for Acute Coronary Syndrome patients with depression ('MoodCare': Study protocol

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Hare David L

2011-02-01

Full Text Available Abstract Background Coronary heart disease (CHD and depression are leading causes of disease burden globally and the two often co-exist. Depression is common after Myocardial Infarction (MI and it has been estimated that 15-35% of patients experience depressive symptoms. Co-morbid depression can impair health related quality of life (HRQOL, decrease medication adherence and appropriate utilisation of health services, lead to increased morbidity and suicide risk, and is associated with poorer CHD risk factor profiles and reduced survival. We aim to determine the feasibility of conducting a randomised, multi-centre trial designed to compare a tele-health program (MoodCare for depression and CHD secondary prevention, with Usual Care (UC. Methods Over 1600 patients admitted after index admission for Acute Coronary Syndrome (ACS are being screened for depression at six metropolitan hospitals in the Australian states of Victoria and Queensland. Consenting participants are then contacted at two weeks post-discharge for baseline assessment. One hundred eligible participants are to be randomised to an intervention or a usual medical care control group (50 per group. The intervention consists of up to 10 × 30-40 minute structured telephone sessions, delivered by registered psychologists, commencing within two weeks of baseline screening. The intervention focuses on depression management, lifestyle factors (physical activity, healthy eating, smoking cessation, alcohol intake, medication adherence and managing co-morbidities. Data collection occurs at baseline (Time 1, 6 months (post-intervention (Time 2, 12 months (Time 3 and 24 months follow-up for longer term effects (Time 4. We are comparing depression (Cardiac Depression Scale [CDS] and HRQOL (Short Form-12 [SF-12] scores between treatment and UC groups, assessing the feasibility of the program through patient acceptability and exploring long term maintenance effects. A cost-effectiveness analysis of

Community health promotion and medical provision for neonatal health-CHAMPION cluster randomised trial in Nagarkurnool district, Telangana (formerly Andhra Pradesh, India.

Directory of Open Access Journals (Sweden)

Peter Boone

2017-07-01

Full Text Available In the mid-2000s, neonatal mortality accounted for almost 40% of deaths of children under 5 years worldwide, and constituted 65% of infant deaths in India. The neonatal mortality rate in Andhra Pradesh was 44 per 1,000 live births, and was higher in the rural areas and tribal regions, such as the Nagarkurnool division of Mahabubnagar district (which became Nagarkurnool district in Telangana in 2014. The aim of the CHAMPION trial was to investigate whether a package of interventions comprising community health promotion and provision of health services (including outreach and facility-based care could lead to a reduction of the order of 25% in neonatal mortality.The design was a trial in which villages (clusters in Nagarkurnool with a population < 2,500 were randomised to the CHAMPION package of health interventions or to the control arm (in which children aged 6-9 years were provided with educational interventions-the STRIPES trial. A woman was eligible for the CHAMPION package if she was married and <50 years old, neither she nor her husband had had a family planning operation, and she resided in a trial village at the time of a baseline survey before randomisation or married into the village after randomisation. The CHAMPION intervention package comprised community health promotion (including health education via village health worker-led participatory discussion groups and provision of health services (including outreach, with mobile teams providing antenatal check-ups, and facility-based care, with subsidised access to non-public health centres [NPHCs]. Villages were stratified by travel time to the nearest NPHC and tribal status, and randomised (1:1 within strata. The primary outcome was neonatal mortality. Secondary outcomes included maternal mortality, causes of death, health knowledge, health practices including health service usage, satisfaction with care, and costs. The baseline survey (enumeration was carried out between August and

The Children and Parents in Focus project: a population-based cluster-randomised controlled trial to prevent behavioural and emotional problems in children.

Science.gov (United States)

Salari, Raziye; Fabian, Helena; Prinz, Ron; Lucas, Steven; Feldman, Inna; Fairchild, Amanda; Sarkadi, Anna

2013-10-16

There is large body of knowledge to support the importance of early interventions to improve child health and development. Nonetheless, it is important to identify cost-effective blends of preventive interventions with adequate coverage and feasible delivery modes. The aim of the Children and Parents in Focus trial is to compare two levels of parenting programme intensity and rate of exposure, with a control condition to address impact and cost-effectiveness of a universally offered evidence-based parenting programme in the Swedish context. The trial has a cluster randomised controlled design comprising three arms: Universal arm (with access to participation in Triple P - Positive Parenting Program, level 2); Universal Plus arm (with access to participation in Triple P - Positive Parenting Program, level 2 as well as level 3, and level 4 group); and Services as Usual arm. The sampling frame is Uppsala municipality in Sweden. Child health centres consecutively recruit parents of children aged 3 to 5 years before their yearly check-ups (during the years 2013-2017). Outcomes will be measured annually. The primary outcome will be children's behavioural and emotional problems as rated by three informants: fathers, mothers and preschool teachers. The other outcomes will be parents' behaviour and parents' general health. Health economic evaluations will analyse cost-effectiveness of the interventions versus care as usual by comparing the costs and consequences in terms of impact on children's mental health, parent's mental health and health-related quality of life. This study addresses the need for comprehensive evaluation of the long-term effects, costs and benefits of early parenting interventions embedded within existing systems. In addition, the study will generate population-based data on the mental health and well-being of preschool aged children in Sweden. ISRCTN16513449.

Return-to-work intervention versus usual care for sick-listed employees: health-economic investment appraisal alongside a cluster randomised trial

Science.gov (United States)

Lokman, Suzanne; Volker, Danielle; Zijlstra-Vlasveld, Moniek C; Brouwers, Evelien PM; Boon, Brigitte; Beekman, Aartjan TF; Smit, Filip; Van der Feltz-Cornelis, Christina M

2017-01-01

Objective To evaluate the health-economic costs and benefits of a guided eHealth intervention (E-health module embedded in Collaborative Occupational healthcare (ECO)) encouraging sick-listed employees to a faster return to work. Design A two-armed cluster randomised trial with occupational physicians (OPs) (n=62), clustered and randomised by region into an experimental and a control group, to conduct a health-economic investment appraisal. Online self-reported data were collected from employees at baseline, after 3, 6, 9 and 12 months. Setting Occupational health care in the Netherlands. Participants Employees from small-sized and medium-sized companies (≥18 years), sick-listed between 4 and 26 weeks with (symptoms of) common mental disorders visiting their OP. Interventions In the intervention group, employees (N=131) received an eHealth module aimed at changing cognitions regarding return to work, while OPs were supported by a decision aid for treatment and referral options. Employees in the control condition (N=89) received usual sickness guidance. Outcomes Measures Net benefits and return on investment based on absenteeism, presenteeism, health care use and quality-adjusted life years (QALYs) gained. Results From the employer’s perspective, the incremental net benefits were €3187 per employee over a single year, representing a return of investment of €11 per invested Euro, with a break-even point at 6 months. The economic case was also favourable from the employee’s perspective, partly because of QALY health gains. The intervention was costing €234 per employee from a health service financier’s perspective. The incremental net benefits from a social perspective were €4210. This amount dropped to €3559 in the sensitivity analysis trimming the 5% highest costs. Conclusions The data suggest that the ECO intervention offers good value for money for virtually all stakeholders involved, because initial investments were more than recouped within a

THE TYPE II SUPERNOVA RATE IN z {approx} 0.1 GALAXY CLUSTERS FROM THE MULTI-EPOCH NEARBY CLUSTER SURVEY

Energy Technology Data Exchange (ETDEWEB)

Graham, M. L.; Sand, D. J. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Bildfell, C. J.; Pritchet, C. J. [Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, STN CSC, Victoria BC V8W 3P6 (Canada); Zaritsky, D.; Just, D. W.; Herbert-Fort, S. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Hoekstra, H. [Leiden Observatory, Leiden University, Niels Bohrweg 2, NL-2333 CA Leiden (Netherlands); Sivanandam, S. [Dunlap Institute for Astronomy and Astrophysics, 50 St. George St., Toronto, ON M5S 3H4 (Canada); Foley, R. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2012-07-01

We present seven spectroscopically confirmed Type II cluster supernovae (SNe II) discovered in the Multi-Epoch Nearby Cluster Survey, a supernova survey targeting 57 low-redshift 0.05 < z < 0.15 galaxy clusters with the Canada-France-Hawaii Telescope. We find the rate of Type II supernovae within R{sub 200} of z {approx} 0.1 galaxy clusters to be 0.026{sup +0.085}{sub -0.018}(stat){sup +0.003}{sub -0.001}(sys) SNuM. Surprisingly, one SN II is in a red-sequence host galaxy that shows no clear evidence of recent star formation (SF). This is unambiguous evidence in support of ongoing, low-level SF in at least some cluster elliptical galaxies, and illustrates that galaxies that appear to be quiescent cannot be assumed to host only Type Ia SNe. Based on this single SN II we make the first measurement of the SN II rate in red-sequence galaxies, and find it to be 0.007{sup +0.014}{sub -0.007}(stat){sup +0.009}{sub -0.001}(sys) SNuM. We also make the first derivation of cluster specific star formation rates (sSFR) from cluster SN II rates. We find that for all galaxy types the sSFR is 5.1{sup +15.8}{sub -3.1}(stat) {+-} 0.9(sys) M{sub Sun} yr{sup -1} (10{sup 12} M{sub Sun }){sup -1}, and for red-sequence galaxies only it is 2.0{sup +4.2}{sub -0.9}(stat) {+-} 0.4(sys) M{sub Sun} yr{sup -1} (10{sup 12} M{sub Sun }){sup -1}. These values agree with SFRs measured from infrared and ultraviolet photometry, and H{alpha} emission from optical spectroscopy. Additionally, we use the SFR derived from our SNII rate to show that although a small fraction of cluster Type Ia SNe may originate in the young stellar population and experience a short delay time, these results do not preclude the use of cluster SN Ia rates to derive the late-time delay time distribution for SNe Ia.

Translating Evidence for Low Back Pain Management into a Consumer-Focussed Resource for Use in Community Pharmacies: A Cluster-Randomised Controlled Trial

Science.gov (United States)

2013-01-01

Background This cluster-randomised controlled trial determined the effectiveness of an evidence-based, pamphlet intervention in improving low back pain (LBP)-related beliefs among pharmacy consumers. Methods Thirty five community pharmacies were randomised to three groups: pamphlet+education intervention [n = 11]; pamphlet only intervention [n = 11]; control: usual care [n = 13]. Eligibility requirements for clusters included: community-based pharmacies and proprietor participation consent. Pharmacy consumers (N = 317) aged 18–65 years currently experiencing LBP participated. Intervention group allocation depended on the pharmacy attended. Individual-level outcomes were measured at pre-intervention (T0), at two (T1) and eight (T2) weeks post-intervention and included beliefs about LBP [Back Pain Beliefs Questionnaire (BBQ); Fear Avoidance Beliefs Questionnaire (FABQ)]. Secondary outcomes included pain severity, activity impairment and pamphlet perceived usefulness. Blinding to group allocation included primary investigators, outcome assessors and the statistician. Pharmacy staff and consumers were un-blinded. Results Of 35 pharmacies recruited (317 consumers), no clusters were lost to follow-up. Follow-up was available for n = 24 at 2 weeks only; n = 38 at 8 weeks only; n = 148 at both time points, with n = 148+24+38 = 210 analysed (107 excluded: no follow up). Adjusting for baseline scores demonstrated no significant differences in beliefs (2 or at 8 weeks) between pamphlet (with or without education) versus control, or between ‘pamphlet with’ versus ‘without’ education. Work-related fear (FABQ) was significantly lower in consumers receiving pamphlet (with or without education) versus control (difference −2.3, 95%CI: −4.4 to −0.2). There was no significant difference between “pamphlet with” versus “pamphlet without” groups. Consumers receiving the “pamphlet with” reported greater perceived usefulness

Wandering off the centre: a characterization of the random motion of intermediate-mass black holes in star clusters

Science.gov (United States)

de Vita, Ruggero; Trenti, Michele; MacLeod, Morgan

2018-04-01

Despite recent observational efforts, unequivocal signs for the presence of intermediate-mass black holes (IMBHs) in globular clusters (GCs) have not been found yet. Especially when the presence of IMBHs is constrained through dynamical modelling of stellar kinematics, it is fundamental to account for the displacement that the IMBH might have with respect to the GC centre. In this paper, we analyse the IMBH wandering around the stellar density centre using a set of realistic direct N-body simulations of star cluster evolution. Guided by the simulation results, we develop a basic yet accurate model that can be used to estimate the average IMBH radial displacement (〈rbh〉) in terms of structural quantities as the core radius (rc), mass (Mc), and velocity dispersion (σc), in addition to the average stellar mass (mc) and the IMBH mass (Mbh). The model can be expressed by the equation /r_c=A(m_c/M_bh)^α [σ _c^2r_c/(GM_c)]^β, in which the free parameters A, α, and β are calculated through comparison with the numerical results on the IMBH displacement. The model is then applied to Galactic GCs, finding that for an IMBH mass equal to 0.1 per cent of the GC mass, the typical expected displacement of a putative IMBH is around 1 arcsec for most Galactic GCs, but IMBHs can wander to larger angular distances in some objects, including a prediction of a 2.5 arcsec displacement for NGC 5139 (ω Cen), and >10 arcsec for NGC5053, NGC6366, and ARP2.

Effects of a free school breakfast programme on school attendance, achievement, psychosocial function, and nutrition: a stepped wedge cluster randomised trial

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Maddison Ralph

2010-11-01

Full Text Available Abstract Background Approximately 55,000 children in New Zealand do not eat breakfast on any given day. Regular breakfast skipping has been associated with poor diets, higher body mass index, and adverse effects on children's behaviour and academic performance. Research suggests that regular breakfast consumption can improve academic performance, nutrition and behaviour. This paper describes the protocol for a stepped wedge cluster randomised trial of a free school breakfast programme. The aim of the trial is to determine the effects of the breakfast intervention on school attendance, achievement, psychosocial function, dietary habits and food security. Methods/Design Sixteen primary schools in the North Island of New Zealand will be randomised in a sequential stepped wedge design to a free before-school breakfast programme consisting of non-sugar coated breakfast cereal, milk products, and/or toast and spreads. Four hundred children aged 5-13 years (approximately 25 per school will be recruited. Data collection will be undertaken once each school term over the 2010 school year (February to December. The primary trial outcome is school attendance, defined as the proportion of students achieving an attendance rate of 95% or higher. Secondary outcomes are academic achievement (literacy, numeracy, self-reported grades, sense of belonging at school, psychosocial function, dietary habits, and food security. A concurrent process evaluation seeks information on parents', schools' and providers' perspectives of the breakfast programme. Discussion This randomised controlled trial will provide robust evidence of the effects of a school breakfast programme on students' attendance, achievement and nutrition. Furthermore the study provides an excellent example of the feasibility and value of the stepped wedge trial design in evaluating pragmatic public health intervention programmes. Trial Registration Number Australian New Zealand Clinical Trials Registry

Effectiveness of adenoidectomy in children with recurrent upper respiratory tract infections: open randomised controlled trial.

NARCIS (Netherlands)

Aardweg, M.T. van den; Boonacker, C.W.; Rovers, M.M.; Hoes, A.W.; Schilder, A.G.M.

2011-01-01

OBJECTIVE: To assess the effectiveness of adenoidectomy in children with recurrent upper respiratory tract infections. DESIGN: Open randomised controlled trial. SETTING: 11 general hospitals and two academic centres. PARTICIPANTS: 111 children aged 1-6 with recurrent upper respiratory tract

Study on dependence of dose enhancement on cluster morphology of gold nanoparticles in radiation therapy using a body-centred cubic model

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Ahn, Sang Hee; Chung, Kwangzoo; Shin, Jung Wook; Cheon, Wonjoong; Han, Youngyih; Park, Hee Chul; Choi, Doo Ho

2017-10-01

Gold nanoparticles (GNPs) injected in a body for dose enhancement in radiation therapy are known to form clusters. We investigated the dependence of dose enhancement on the GNP morphology using Monte-Carlo simulations and compared the model predictions with experimental data. The cluster morphology was approximated as a body-centred cubic (BCC) structure by placing GNPs at the 8 corners and the centre of a cube with an edge length of 0.22-1.03 µm in a 4  ×  4  ×  4 µm3 water-filled phantom. We computed the dose enhancement ratio (DER) for 50 and 260 kVp photons as a function of the distance from the cube centre for 12 different cube sizes. A 10 nm-wide concentric shell shaped detector was placed up to 100 nm away from a GNP at the cube centre. For model validation, simulations based on BCC and nanoparticle random distribution (NRD) models were performed using parameters that corresponded to the experimental conditions, which measured increases in the relative biological effect due to GNPs. We employed the linear quadratic model to compute cell surviving fraction (SF) and sensitizer enhancement ratio (SER). The DER is inversely proportional to the distance to the GNPs. The largest DERs were 1.97 and 1.80 for 50 kVp and 260 kVp photons, respectively. The SF predicted by the BCC model agreed with the experimental value within 10%, up to a 5 Gy dose, while the NRD model showed a deviation larger than 10%. The SERs were 1.21  ±  0.13, 1.16  ±  0.11, and 1.08  ±  0.11 according to the experiment, BCC, and NRD models, respectively. We most accurately predicted the GNP radiosensitization effect using the BCC approximation and suggest that the BCC model is effective for use in nanoparticle dosimetry.

Delivering early care in diabetes evaluation (DECIDE: a protocol for a randomised controlled trial to assess hospital versus home management at diagnosis in childhood diabetes

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Robling Michael

2011-01-01

Full Text Available Abstract Background There is increased incidence of new cases of type 1 diabetes in children younger than 15 years. The debate concerning where best to manage newly diagnosed children continues. Some units routinely admit children to hospital whilst others routinely manage children at home. A Cochrane review identified the need for a large well-designed randomised controlled trial to investigate any significant differences in comprehensive short and long-term outcomes between the two approaches. The DECIDE study will address these knowledge gaps, providing high quality evidence to inform national and international policy and practice. Methods/Design This is a multi-centre randomised controlled trial across eight UK paediatric diabetes centres. The study aims to recruit 240 children newly diagnosed with type 1 diabetes and their parents/carers. Eligible patients (aged 0-17 years will be remotely randomised to either 'hospital' or 'home' management. Parents/carers of patients will also be recruited. Nursing management of participants and data collection will be co-ordinated by a project nurse at each centre. Data will be collected for 24 months after diagnosis; at follow up appointments at 3, 12 and 24 months and every 3-4 months at routine clinic visits. The primary outcome measure is patients' glycosylated haemoglobin (HbA1c at 24 months after diagnosis. Additional measurements of HbA1c will be made at diagnosis and 3 and 12 months later. HbA1c concentrations will be analysed at a central laboratory. Secondary outcome measures include length of stay at diagnosis, growth, adverse events, quality of life, anxiety, coping with diabetes, diabetes knowledge, home/clinic visits, self-care activity, satisfaction and time off school/work. Questionnaires will be sent to participants at 1, 12 and 24 months and will include a questionnaire, developed and validated to measure impact of the diagnosis on social activity and independence. Additional

Financial considerations in the conduct of multi-centre randomised controlled trials: evidence from a qualitative study

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Grant Adrian M

2006-12-01

Full Text Available Abstract Background Securing and managing finances for multicentre randomised controlled trials is a highly complex activity which is rarely considered in the research literature. This paper describes the process of financial negotiation and the impact of financial considerations in four UK multicentre trials. These trials had met, or were on schedule to meet, recruitment targets agreed with their public-sector funders. The trials were considered within a larger study examining factors which might be associated with trial recruitment (STEPS. Methods In-depth semi-structured telephone interviews were conducted in 2003–04 with 45 individuals with various responsibilities to one of the four trials. Interviewees were recruited through purposive and then snowball sampling. Interview transcripts were analysed with the assistance of the qualitative package Atlas-ti. Results The data suggest that the UK system of dividing funds into research, treatment and NHS support costs brought the trial teams into complicated negotiations with multiple funders. The divisions were somewhat malleable and the funding system was used differently in each trial. The fact that all funders had the potential to influence and shape the trials considered here was an important issue as the perspectives of applicants and funders could diverge. The extent and range of industry involvement in non-industry-led trials was striking. Three broad periods of financial work (foundation, maintenance, and resourcing completion were identified. From development to completion of a trial, the trialists had to be resourceful and flexible, adapting to changing internal and external circumstances. In each period, trialists and collaborators could face changing costs and challenges. Each trial extended the recruitment period; three required funding extensions from MRC or HTA. Conclusion This study highlights complex financial aspects of planning and conducting trials, especially where multiple

Financial considerations in the conduct of multi-centre randomised controlled trials: evidence from a qualitative study.

Science.gov (United States)

Snowdon, Claire; Elbourne, Diana R; Garcia, Jo; Campbell, Marion K; Entwistle, Vikki A; Francis, David; Grant, Adrian M; Knight, Rosemary C; McDonald, Alison M; Roberts, Ian

2006-12-21

Securing and managing finances for multicentre randomised controlled trials is a highly complex activity which is rarely considered in the research literature. This paper describes the process of financial negotiation and the impact of financial considerations in four UK multicentre trials. These trials had met, or were on schedule to meet, recruitment targets agreed with their public-sector funders. The trials were considered within a larger study examining factors which might be associated with trial recruitment (STEPS). In-depth semi-structured telephone interviews were conducted in 2003-04 with 45 individuals with various responsibilities to one of the four trials. Interviewees were recruited through purposive and then snowball sampling. Interview transcripts were analysed with the assistance of the qualitative package Atlas-ti. The data suggest that the UK system of dividing funds into research, treatment and NHS support costs brought the trial teams into complicated negotiations with multiple funders. The divisions were somewhat malleable and the funding system was used differently in each trial. The fact that all funders had the potential to influence and shape the trials considered here was an important issue as the perspectives of applicants and funders could diverge. The extent and range of industry involvement in non-industry-led trials was striking. Three broad periods of financial work (foundation, maintenance, and resourcing completion) were identified. From development to completion of a trial, the trialists had to be resourceful and flexible, adapting to changing internal and external circumstances. In each period, trialists and collaborators could face changing costs and challenges. Each trial extended the recruitment period; three required funding extensions from MRC or HTA. This study highlights complex financial aspects of planning and conducting trials, especially where multiple funders are involved. Recognition of the importance of financial

EXTUBATE: A randomised controlled trial of nasal biphasic positive airway pressure vs. nasal continuous positive airway pressure following extubation in infants less than 30 weeks' gestation: study protocol for a randomised controlled trial

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Victor Suresh

2011-12-01

Full Text Available Abstract Background Respiratory distress syndrome remains a significant problem among premature infants. Mechanical ventilation through an endotracheal tube remains the mainstay of respiratory support but may be associated with lung injury and the development of chronic lung disease of prematurity. Efforts are needed to reduce the duration of mechanical ventilation in favour of less invasive forms of respiratory support and to improve rates of successful extubation. Non-invasive respiratory support has been demonstrated to be less injurious to the premature lung. Standard practice is to use nasal continuous positive airway pressure (n-CPAP following extubation to support the baby's breathing. Many clinicians also use nasal biphasic positive airway pressure (n-BiPAP in efforts to improve rates of successful extubation. However, there is currently no evidence that this confers any advantage over conventional nasal continuous positive airway pressure. Methods We propose an unblinded multi-centre randomised trial comparing n-CPAP with n-BiPAP in babies born before 30 weeks' gestation and less than two weeks old. Babies with congenital abnormalities and severe intra-ventricular haemorrhage will be excluded. 540 babies admitted to neonatal centres in England will be randomised at the time of first extubation attempt. The primary aim of this study is to compare the rate of extubation failure within 48 hours following the first attempt at extubation. The secondary aims are to compare the effect of n-BiPAP and n-CPAP on the following outcomes: 1. Maintenance of successful extubation for 7 days post extubation 2. Oxygen requirement at 28 days of age and at 36 weeks' corrected gestational age 3. Total days on ventilator, n-CPAP/n-BiPAP 4. Number of ventilator days following first extubation attempt 5. pH and partial pressure of carbon dioxide in the first post extubation blood gas 6. Duration of hospital stay 7. Rate of abdominal distension requiring

Influence of quality of care and individual patient characteristics on quality of life and return to work in survivors of the acute respiratory distress syndrome: protocol for a prospective, observational, multi-centre patient cohort study (DACAPO).

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Brandstetter, Susanne; Dodoo-Schittko, Frank; Blecha, Sebastian; Sebök, Philipp; Thomann-Hackner, Kathrin; Quintel, Michael; Weber-Carstens, Steffen; Bein, Thomas; Apfelbacher, Christian

2015-12-17

Health-related quality of life (HRQoL) and return to work are important outcomes in critical care medicine, reaching beyond mortality. Little is known on factors predictive of HRQoL and return to work in critical illness, including the acute respiratory distress syndrome (ARDS), and no evidence exists on the role of quality of care (QoC) for outcomes in survivors of ARDS. It is the aim of the DACAPO study ("Surviving ARDS: the influence of QoC and individual patient characteristics on quality of life") to investigate the role of QoC and individual patient characteristics on quality of life and return to work. A prospective, observational, multi-centre patient cohort study will be performed in Germany, using hospitals from the "ARDS Network Germany" as the main recruiting centres. It is envisaged to recruit 2400 patients into the DACAPO study and to analyse a study population of 1500 survivors. They will be followed up until 12 months after discharge from hospital. QoC will be assessed as process quality, structural quality and volume at the institutional level. The main outcomes (HRQoL and return to work) will be assessed by self-report questionnaires. Further data collection includes general medical and ARDS-related characteristics of patients as well as sociodemographic and psycho-social parameters. Multilevel hierarchical modelling will be performed to analyse the effects of QoC and individual patient characteristics on outcomes, taking the cluster structure of the data into account. By obtaining comprehensive data at patient and hospital level using a prospective multi-centre design, the DACAPO-study is the first study investigating the influence of QoC on individual outcomes of ARDS survivors.

A formal concept analysis approach to consensus clustering of multi-experiment expression data

Science.gov (United States)

2014-01-01

Background Presently, with the increasing number and complexity of available gene expression datasets, the combination of data from multiple microarray studies addressing a similar biological question is gaining importance. The analysis and integration of multiple datasets are expected to yield more reliable and robust results since they are based on a larger number of samples and the effects of the individual study-specific biases are diminished. This is supported by recent studies suggesting that important biological signals are often preserved or enhanced by multiple experiments. An approach to combining data from different experiments is the aggregation of their clusterings into a consensus or representative clustering solution which increases the confidence in the common features of all the datasets and reveals the important differences among them. Results We propose a novel generic consensus clustering technique that applies Formal Concept Analysis (FCA) approach for the consolidation and analysis of clustering solutions derived from several microarray datasets. These datasets are initially divided into groups of related experiments with respect to a predefined criterion. Subsequently, a consensus clustering algorithm is applied to each group resulting in a clustering solution per group. These solutions are pooled together and further analysed by employing FCA which allows extracting valuable insights from the data and generating a gene partition over all the experiments. In order to validate the FCA-enhanced approach two consensus clustering algorithms are adapted to incorporate the FCA analysis. Their performance is evaluated on gene expression data from multi-experiment study examining the global cell-cycle control of fission yeast. The FCA results derived from both methods demonstrate that, although both algorithms optimize different clustering characteristics, FCA is able to overcome and diminish these differences and preserve some relevant biological

Effects of circuit training as alternative to usual physiotherapy after stroke: randomised controlled trial

NARCIS (Netherlands)

van de Port, I.G.L.; Wevers, L.E.G.; Lindeman, E.; Kwakkel, G.

2012-01-01

Objective: To analyse the effect of task oriented circuit training compared with usual physiotherapy in terms of self reported walking competency for patients with stroke discharged from a rehabilitation centre to their own home. Design: Randomised controlled trial with follow-up to 24 weeks.

Species distribution and susceptibility profile to fluconazole, voriconazole and MXP-4509 of 551 clinical yeast isolates from a Romanian multi-centre study

NARCIS (Netherlands)

Minea, B; Nastasa, V; Moraru, R F; Kolecka, A; Flonta, M M; Marincu, I; Man, A; Toma, F; Lupse, M; Doroftei, B; Marangoci, N; Pinteala, M; Boekhout, T; Mares, M

This is the first multi-centre study regarding yeast infections in Romania. The aim was to determine the aetiological spectrum and susceptibility pattern to fluconazole, voriconazole and the novel compound MXP-4509. The 551 isolates were identified using routine laboratory methods, matrix-assisted

Size effects in van der Waals clusters studied by spin and angle-resolved electron spectroscopy and multi-coincidence ion imaging

International Nuclear Information System (INIS)

Rolles, D; Pesic, Z D; Zhang, H; Bilodeau, R C; Bozek, J D; Berrah, N

2007-01-01

We have studied the valence and inner-shell photoionization of free rare-gas clusters by means of angle and spin resolved photoelectron spectroscopy and momentum resolving electron-multi-ion coincidence spectroscopy. The electron measurements probe the evolution of the photoelectron angular distribution and spin polarization parameters as a function of photon energy and cluster size, and reveal a strong cluster size dependence of the photoelectron angular distributions in certain photon energy regions. In contrast, the spin polarization parameter of the cluster photoelectrons is found to be very close to the atomic value for all covered photon energies and cluster sizes. The ion imaging measurements, which probe the fragmentation dynamics of multiply charged van der Waals clusters, also exhibit a pronounced cluster size dependence

A healthy school start - Parental support to promote healthy dietary habits and physical activity in children: Design and evaluation of a cluster-randomised intervention

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