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Sample records for multiple cohort analysis

  1. Multiple pregnancies achieved with IVF/ICSI and risk of specific congenital malformations: a meta-analysis of cohort studies.

    Science.gov (United States)

    Zheng, Zan; Chen, Letao; Yang, Tubao; Yu, Hong; Wang, Hua; Qin, Jiabi

    2018-04-01

    Studies comparing risk of specific congenital malformations (CM) between multiple pregnancies resulting from IVF/intracytoplasmic sperm injection (ICSI) and those conceived naturally report conflicting results; furthermore, there is a lack of a complete overview. This meta-analysis aimed to address which types of CM are increased in IVF/ICSI multiple pregnancies compared with those conceived naturally. All studies testing the association between IVF/ICSI multiple pregnancies and specific CM identified in various databases were considered. The literature search yielded 856 records, of which 21 cohort studies were included for analysis. Overall, multiple pregnancies achieved with IVF/ICSI experienced a significantly higher risk of chromosomal defects (relative risk [RR] = 1.36; 95% confidence interval [CI]: 1.04-1.77), urogenital (RR = 1.18; 95% CI: 1.03-1.36) and circulatory (RR = 1.22; 95% CI: 1.01-1.47) system malformations. However, the remaining specific CM, such as cleft lip and/or palate, eye, ear, face and neck, respiratory, musculoskeletal, nervous and digestive system malformations, were similar in the two groups. No substantial heterogeneity was observed for most outcomes except for digestive (P = 0.094; I 2 = 38.3%) and circulatory (P = 0.070; I 2 = 35.2%) system malformations. These findings provide additional information on risks of IVF/ICSI for use when counselling patients. Copyright © 2018 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  2. Analysis of vestibular schwannoma size in multiple dimensions: a comparative cohort study of different measurement techniques.

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    Varughese, J K; Wentzel-Larsen, T; Vassbotn, F; Moen, G; Lund-Johansen, M

    2010-04-01

    In this volumetric study of the vestibular schwannoma, we evaluated the accuracy and reliability of several approximation methods that are in use, and determined the minimum volume difference that needs to be measured for it to be attributable to an actual difference rather than a retest error. We also found empirical proportionality coefficients for the different methods. DESIGN/SETTING AND PARTICIPANTS: Methodological study with investigation of three different VS measurement methods compared to a reference method that was based on serial slice volume estimates. These volume estimates were based on: (i) one single diameter, (ii) three orthogonal diameters or (iii) the maximal slice area. Altogether 252 T1-weighted MRI images with gadolinium contrast, from 139 VS patients, were examined. The retest errors, in terms of relative percentages, were determined by undertaking repeated measurements on 63 scans for each method. Intraclass correlation coefficients were used to assess the agreement between each of the approximation methods and the reference method. The tendency for approximation methods to systematically overestimate/underestimate different-sized tumours was also assessed, with the help of Bland-Altman plots. The most commonly used approximation method, the maximum diameter, was the least reliable measurement method and has inherent weaknesses that need to be considered. This includes greater retest errors than area-based measurements (25% and 15%, respectively), and that it was the only approximation method that could not easily be converted into volumetric units. Area-based measurements can furthermore be more reliable for smaller volume differences than diameter-based measurements. All our findings suggest that the maximum diameter should not be used as an approximation method. We propose the use of measurement modalities that take into account growth in multiple dimensions instead.

  3. Causal relationship between obesity and vitamin D status: bi-directional Mendelian randomization analysis of multiple cohorts.

    Directory of Open Access Journals (Sweden)

    Karani S Vimaleswaran

    Full Text Available Obesity is associated with vitamin D deficiency, and both are areas of active public health concern. We explored the causality and direction of the relationship between body mass index (BMI and 25-hydroxyvitamin D [25(OHD] using genetic markers as instrumental variables (IVs in bi-directional Mendelian randomization (MR analysis.We used information from 21 adult cohorts (up to 42,024 participants with 12 BMI-related SNPs (combined in an allelic score to produce an instrument for BMI and four SNPs associated with 25(OHD (combined in two allelic scores, separately for genes encoding its synthesis or metabolism as an instrument for vitamin D. Regression estimates for the IVs (allele scores were generated within-study and pooled by meta-analysis to generate summary effects. Associations between vitamin D scores and BMI were confirmed in the Genetic Investigation of Anthropometric Traits (GIANT consortium (n = 123,864. Each 1 kg/m(2 higher BMI was associated with 1.15% lower 25(OHD (p = 6.52×10⁻²⁷. The BMI allele score was associated both with BMI (p = 6.30×10⁻⁶² and 25(OHD (-0.06% [95% CI -0.10 to -0.02], p = 0.004 in the cohorts that underwent meta-analysis. The two vitamin D allele scores were strongly associated with 25(OHD (p≤8.07×10⁻⁵⁷ for both scores but not with BMI (synthesis score, p = 0.88; metabolism score, p = 0.08 in the meta-analysis. A 10% higher genetically instrumented BMI was associated with 4.2% lower 25(OHD concentrations (IV ratio: -4.2 [95% CI -7.1 to -1.3], p = 0.005. No association was seen for genetically instrumented 25(OHD with BMI, a finding that was confirmed using data from the GIANT consortium (p≥0.57 for both vitamin D scores.On the basis of a bi-directional genetic approach that limits confounding, our study suggests that a higher BMI leads to lower 25(OHD, while any effects of lower 25(OHD increasing BMI are likely to be small. Population level interventions to

  4. Delayed Diagnosis, Range of Severity, and Multiple Sleep Comorbidities: A Clinical and Polysomnographic Analysis of 100 Patients of the Innsbruck Narcolepsy Cohort

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    Frauscher, Birgit; Ehrmann, Laura; Mitterling, Thomas; Gabelia, David; Gschliesser, Viola; Brandauer, Elisabeth; Poewe, Werner; Högl, Birgit

    2013-01-01

    Study Objectives: Narcolepsy is reported to affect 26-56/100,000 in the general population. We aimed to describe clinical and polysomnographic features of a large narcolepsy cohort in order to comprehensively characterize the narcoleptic spectrum. Methods: We performed a chart- and polysomnographybased review of all narcolepsy patients of the Innsbruck narcolepsy cohort. Results: A total of 100 consecutive narcolepsy patients (87 with cataplexy [NC], 13 without cataplexy [N]) were included in the analysis. All subjects had either excessive daytime sleepiness or cataplexy as their initial presenting clinical feature. Age at symptom onset was 20 (6-69) years. Diagnostic delay was 6.5 (0-39) years. The complete narcolepsy tetrad was present in 36/100 patients; 28/100 patients had three cardinal symptoms; 29/100 had two; and 7/100 had only excessive daytime sleepiness. Severity varied broadly with respect to excessive daytime sleepiness (median Epworth Sleepiness Scale score: 18, range 10-24), cataplexy (8-point Likert scale: median 4.5, range 1-8), hypnagogic hallucinations (median 4.5, range 1-7), and sleep paralysis (median 3, range 1-7). Sleep comorbidity was highly prevalent and ranged from sleeprelated movement disorders (n = 55/100), parasomnias (n = 34/100), and sleeprelated breathing disorders (n = 24/100), to insomnia (n = 28/100). REM sleep without atonia or a periodic limb movement in sleep index > 5/h were present in most patients (90/100 and 75/100). A high percentage of narcoleptic patients in the present study had high frequency leg movements (35%) and excessive fragmentary myoclonus (22%). Of the narcolepsy patients with clinical features of REM sleep behavior disorder (RBD), 76.5% had EMG evidence for RBD on the multiple sleep latency test (MSLT), based on a standard cutoff of a minimum of 18% of 3-sec miniepochs. Conclusion: This study is one of the largest monocentric polysomnographic studies to date of patients with narcolepsy and confirms the

  5. Neutron Multiplicity Analysis

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    Frame, Katherine Chiyoko [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-28

    Neutron multiplicity measurements are widely used for nondestructive assay (NDA) of special nuclear material (SNM). When combined with isotopic composition information, neutron multiplicity analysis can be used to estimate the spontaneous fission rate and leakage multiplication of SNM. When combined with isotopic information, the total mass of fissile material can also be determined. This presentation provides an overview of this technique.

  6. The multiple sclerosis visual pathway cohort: understanding neurodegeneration in MS.

    Science.gov (United States)

    Martínez-Lapiscina, Elena H; Fraga-Pumar, Elena; Gabilondo, Iñigo; Martínez-Heras, Eloy; Torres-Torres, Ruben; Ortiz-Pérez, Santiago; Llufriu, Sara; Tercero, Ana; Andorra, Magi; Roca, Marc Figueras; Lampert, Erika; Zubizarreta, Irati; Saiz, Albert; Sanchez-Dalmau, Bernardo; Villoslada, Pablo

    2014-12-15

    Multiple Sclerosis (MS) is an immune-mediated disease of the Central Nervous System with two major underlying etiopathogenic processes: inflammation and neurodegeneration. The latter determines the prognosis of this disease. MS is the main cause of non-traumatic disability in middle-aged populations. The MS-VisualPath Cohort was set up to study the neurodegenerative component of MS using advanced imaging techniques by focusing on analysis of the visual pathway in a middle-aged MS population in Barcelona, Spain. We started the recruitment of patients in the early phase of MS in 2010 and it remains permanently open. All patients undergo a complete neurological and ophthalmological examination including measurements of physical and disability (Expanded Disability Status Scale; Multiple Sclerosis Functional Composite and neuropsychological tests), disease activity (relapses) and visual function testing (visual acuity, color vision and visual field). The MS-VisualPath protocol also assesses the presence of anxiety and depressive symptoms (Hospital Anxiety and Depression Scale), general quality of life (SF-36) and visual quality of life (25-Item National Eye Institute Visual Function Questionnaire with the 10-Item Neuro-Ophthalmic Supplement). In addition, the imaging protocol includes both retinal (Optical Coherence Tomography and Wide-Field Fundus Imaging) and brain imaging (Magnetic Resonance Imaging). Finally, multifocal Visual Evoked Potentials are used to perform neurophysiological assessment of the visual pathway. The analysis of the visual pathway with advance imaging and electrophysilogical tools in parallel with clinical information will provide significant and new knowledge regarding neurodegeneration in MS and provide new clinical and imaging biomarkers to help monitor disease progression in these patients.

  7. Mortality analysis in the French cohort of uranium miners

    International Nuclear Information System (INIS)

    Vacquier, B.

    2008-10-01

    The objective of this thesis is to contribute to the estimation of radiation-induced risks at low dose rates. This work is based on the cohort of uranium miners French presenting multiple exposures, contamination by internal (radon and uranium dust) and external exposure (gamma radiation). An analysis of the risk of death and the relationship risk exposure was carried out within the cohort of uranium miners after extension of the monitoring until 1999, for cancers diseases and non-cancers. In addition, an analysis taking into account multiple exposures to ionizing radiation was carried out within the framework of this thesis. This analysis has improved knowledge on the risk of mortality associated with low levels of exposure to radon. (author)

  8. Missed epidemics and missing links: international birth cohort trends in multiple sclerosis.

    Science.gov (United States)

    Ajdacic-Gross, V; Tschopp, A; Schmid, M; Bopp, M; Gutzwiller, F

    2013-03-01

    Many hypotheses on the etiopathogenesis of multiple sclerosis (MS) focus on risk factors occurring early in life. This study examined the variability of birth cohort trends in international MS data by means of age-period-cohort (APC) analysis. The data from 25 countries were taken from the WHO mortality database. Data were encoded according to the International Classification of Diseases and covered slightly varying periods between 1951 and 2009. The APC analyses were based on logit models applied to cohort tables with 5-year age- and period intervals. In most countries, the birth cohort estimates peaked in those born in the first half of the 20th century. In countries from Central and Western Europe, the peak concerned those born before and around 1920. A second group of countries (Denmark, Sweden, Italy, Ireland, Scotland) shared a later peak amongst cohorts born in the 1920s and 1930s. Group 3 included Commonwealth countries, the USA and Norway, with a double or extended peak starting in the 1910s or 1920s, and ending by the 1950s. The fourth group, consisting of Mediterranean countries and Finland, was characterized by a steady increase in the birth cohort estimates until the 1950s. The fifth group with countries from Eastern Europe and Japan showed no particular pattern. Birth cohort trends have influenced the change in MS risk across the 20th century in many Western countries. This silent epidemic points to a most important but unknown latent risk factor in MS. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

  9. SUMMIT (Serially Unified Multicenter Multiple Sclerosis Investigation): creating a repository of deeply phenotyped contemporary multiple sclerosis cohorts.

    Science.gov (United States)

    Bove, Riley; Chitnis, Tanuja; Cree, Bruce Ac; Tintoré, Mar; Naegelin, Yvonne; Uitdehaag, Bernard Mj; Kappos, Ludwig; Khoury, Samia J; Montalban, Xavier; Hauser, Stephen L; Weiner, Howard L

    2017-08-01

    There is a pressing need for robust longitudinal cohort studies in the modern treatment era of multiple sclerosis. Build a multiple sclerosis (MS) cohort repository to capture the variability of disability accumulation, as well as provide the depth of characterization (clinical, radiologic, genetic, biospecimens) required to adequately model and ultimately predict a patient's course. Serially Unified Multicenter Multiple Sclerosis Investigation (SUMMIT) is an international multi-center, prospectively enrolled cohort with over a decade of comprehensive follow-up on more than 1000 patients from two large North American academic MS Centers (Brigham and Women's Hospital (Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB; BWH)) and University of California, San Francisco (Expression/genomics, Proteomics, Imaging, and Clinical (EPIC))). It is bringing online more than 2500 patients from additional international MS Centers (Basel (Universitätsspital Basel (UHB)), VU University Medical Center MS Center Amsterdam (MSCA), Multiple Sclerosis Center of Catalonia-Vall d'Hebron Hospital (Barcelona clinically isolated syndrome (CIS) cohort), and American University of Beirut Medical Center (AUBMC-Multiple Sclerosis Interdisciplinary Research (AMIR)). We provide evidence for harmonization of two of the initial cohorts in terms of the characterization of demographics, disease, and treatment-related variables; demonstrate several proof-of-principle analyses examining genetic and radiologic predictors of disease progression; and discuss the steps involved in expanding SUMMIT into a repository accessible to the broader scientific community.

  10. Multiple sclerosis risk sharing scheme: two year results of clinical cohort study with historical comparator.

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    Boggild, Mike; Palace, Jackie; Barton, Pelham; Ben-Shlomo, Yoav; Bregenzer, Thomas; Dobson, Charles; Gray, Richard

    2009-12-02

    To generate evidence on the longer term cost effectiveness of disease modifying treatments in patients with relapsing-remitting multiple sclerosis. Prospective cohort study with historical comparator. Specialist multiple sclerosis clinics in 70 centres in the United Kingdom. Patients with relapsing-remitting multiple sclerosis who started treatment from May 2002 to April 2005 under the UK risk sharing scheme. Treatment with interferon beta or glatiramer acetate in accordance with guidelines of the UK Association of British Neurologists. Observed utility weighted progression in disability at two years' follow-up assessed on the expanded disability status scale (EDSS) compared with that expected by applying the progression rates in a comparator dataset, modified for patients receiving treatment by multiplying by the hazard ratio derived separately for each disease modifying treatment from the randomised trials. In the primary per protocol analysis, progression in disability was worse than that predicted and worse than that in the untreated comparator dataset ("deviation score" of 113%; excess in mean disability status scale 0.28). In sensitivity analyses, however, the deviation score varied from -72% (using raw baseline disability status scale scores, rather than applying a "no improvement" algorithm) to 156% (imputing missing data for year two from progression rates for year one). It is too early to reach any conclusion about the cost effectiveness of disease modifying treatments from this first interim analysis. Important methodological issues, including the need for additional comparator datasets, the potential bias from missing data, and the impact of the "no improvement" rule, will need to be addressed and long term follow-up of all patients is essential to secure meaningful results. Future analyses of the cohort are likely to be more informative, not least because they will be less sensitive to short term fluctuations in disability.

  11. Autoimmune disease prevalence in a multiple sclerosis cohort in Argentina.

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    Farez, Mauricio F; Balbuena Aguirre, María E; Varela, Francisco; Köhler, Alejandro A; Correale, Jorge

    2014-01-01

    Background. Comorbid autoimmune diseases in MS patients have been studied extensively with controversial results. Moreover, no such data exists for Latin-American MS patients. Methods. We conducted a case-control study aimed to establish the prevalence of autoimmune disorders in a cohort of Argentinean MS patients. Results. There were no significant differences in autoimmune disease prevalence in MS patients with respect to controls. The presence of one or more autoimmune disorders did not increase risk of MS (OR 0.85, 95% CI 0.6-1.3). Discussion. Our results indicate absence of increased comorbid autoimmune disease prevalence in MS patients, as well as of increased risk of MS in patients suffering from other autoimmune disorders.

  12. Validation of the fatigue scale for motor and cognitive functions in a danish multiple sclerosis cohort

    DEFF Research Database (Denmark)

    Oervik, M. S.; Sejbaek, T.; Penner, I. K.

    2017-01-01

    Background Our objective was to validate the Danish translation of the Fatigue Scale for Motor and Cognitive Functions (FSMC) in multiple sclerosis (MS) patients. Materials and methods A Danish MS cohort (n = 84) was matched and compared to the original German validation cohort (n = 309) and a he......Background Our objective was to validate the Danish translation of the Fatigue Scale for Motor and Cognitive Functions (FSMC) in multiple sclerosis (MS) patients. Materials and methods A Danish MS cohort (n = 84) was matched and compared to the original German validation cohort (n = 309...... positive correlations between the two fatigue scales implied high convergent validity (total scores: r = 0.851, p gender). Correcting for depression did not result in any significant adjustments of the correlations...

  13. Allergological and Toxicological Aspects in a Multiple Chemical Sensitivity Cohort

    Science.gov (United States)

    Pigatto, Paolo D.; Minoia, Claudio; Ronchi, Anna; Brambilla, Lucia; Ferrucci, Silvia M.; Spadari, Francesco; Passoni, Manuela; Somalvico, Francesco; Bombeccari, Gian Paolo

    2013-01-01

    Background. Multiple chemical sensitivity (MCS) is a chronic condition characterized by an exaggerated response to toxicants. We ascertained the prevalence of allergy to metals and toxicological aspects in MCS patients. Methods. We conducted a retrospective review of medical records of 41 patients with MCS. We performed patch testing (n = 21) for dental series and did lymphocyte transformation test (n = 18) for metals. We measured mercury in samples of blood (n = 19), urine (n = 19), saliva (n = 20), and scalp hair (n = 17) to investigate the association between mercury levels and cases of MCS. Results. The prevalence of metal immune hypersensitivity in a subset of 26 patients was 92.3 percent. Elevations of mercury occurred in 81.2 percent (26 of 32). The mean (±SD) in blood concentrations of mercury was 7.6 ± 13.6 μg/L; mean in urine was 1.9 ± 2.5 μg/L; mean in scalp hair was 2.2 ± 2.5 μg/g; mean in saliva was 38.1 ± 52.1 μg/L. Subgroup analyses showed that elevation of mercury levels in biological matrices were associated with mercury amalgams in patients with MCS (22 patients), compared with controls (8 patients) (odds ratio 11 : 95 percent confidence interval 1.5 to 81.6; P = 0.023). Conclusions. Our data show an increased prevalence of metal allergy and elevation of mercury levels in bioindicators among patients with MCS. PMID:24367721

  14. Symptomen en persoonlijkheidsproblemen voor, tijdens en na langdurige psychoanalytische behandelingen: een multiple-cohort studie

    NARCIS (Netherlands)

    Berghout, C.C.; Zevalkink, D.J.; Jong, J.T.V.M. de

    2010-01-01

    Using a multiple cohort design, we compared symptoms and personality functioning (SCL-90, BDI-II, STAI, IIP-64, MMPI-2) of patients (N = 231) in different phases of long-term psychoanalytic treatment (before, during, end, follow-up). Our results confirmed findings from earlier meta-analyses that

  15. Evaluation of biases present in the cohort multiple randomised controlled trial design : a simulation study

    NARCIS (Netherlands)

    Candlish, Jane; Pate, Alexander; Sperrin, Matthew; Staa, Tjeerd P van

    2017-01-01

    BACKGROUND: The cohort multiple randomised controlled trial (cmRCT) design provides an opportunity to incorporate the benefits of randomisation within clinical practice; thus reducing costs, integrating electronic healthcare records, and improving external validity. This study aims to address a key

  16. Functional Multiple-Set Canonical Correlation Analysis

    Science.gov (United States)

    Hwang, Heungsun; Jung, Kwanghee; Takane, Yoshio; Woodward, Todd S.

    2012-01-01

    We propose functional multiple-set canonical correlation analysis for exploring associations among multiple sets of functions. The proposed method includes functional canonical correlation analysis as a special case when only two sets of functions are considered. As in classical multiple-set canonical correlation analysis, computationally, the…

  17. A birth cohort analysis of dental contact among elderly Americans.

    Science.gov (United States)

    Wolinsky, F D; Arnold, C L

    1989-01-01

    We applied standard cohort and multiple regression techniques to data on the dental utilization rates of 129,191 elderly individuals taken from the 1972, 1973, 1976, 1977, 1980, and 1981 Health Interview Surveys. The results indicate that the marked variation in dental contact rates is a reflection of cohort succession, and not a function of aging per se. Older cohorts having lower dental contact rates are being replaced by younger cohorts having higher dental contact rates. The dental contact rates of the individual birth cohorts themselves are quite stable over time. The results also indicate that economic barriers (especially liquid assets) have become more important than ever before, especially for the oldest-old. These findings have important implications for public policy about the oral health and health care of elderly Americans. PMID:2783297

  18. Mediation Analysis with Multiple Mediators

    OpenAIRE

    VanderWeele, T.J.; Vansteelandt, S.

    2014-01-01

    Recent advances in the causal inference literature on mediation have extended traditional approaches to direct and indirect effects to settings that allow for interactions and non-linearities. In this paper, these approaches from causal inference are further extended to settings in which multiple mediators may be of interest. Two analytic approaches, one based on regression and one based on weighting are proposed to estimate the effect mediated through multiple mediators and the effects throu...

  19. Evaluation of biases present in the cohort multiple randomised controlled trial design: a simulation study

    Directory of Open Access Journals (Sweden)

    Jane Candlish

    2017-01-01

    Full Text Available Abstract Background The cohort multiple randomised controlled trial (cmRCT design provides an opportunity to incorporate the benefits of randomisation within clinical practice; thus reducing costs, integrating electronic healthcare records, and improving external validity. This study aims to address a key concern of the cmRCT design: refusal to treatment is only present in the intervention arm, and this may lead to bias and reduce statistical power. Methods We used simulation studies to assess the effect of this refusal, both random and related to event risk, on bias of the effect estimator and statistical power. A series of simulations were undertaken that represent a cmRCT trial with time-to-event endpoint. Intention-to-treat (ITT, per protocol (PP, and instrumental variable (IV analysis methods, two stage predictor substitution and two stage residual inclusion, were compared for various refusal scenarios. Results We found the IV methods provide a less biased estimator for the causal effect when refusal is present in the intervention arm, with the two stage residual inclusion method performing best with regards to minimum bias and sufficient power. We demonstrate that sample sizes should be adapted based on expected and actual refusal rates in order to be sufficiently powered for IV analysis. Conclusion We recommend running both an IV and ITT analyses in an individually randomised cmRCT as it is expected that the effect size of interest, or the effect we would observe in clinical practice, would lie somewhere between that estimated with ITT and IV analyses. The optimum (in terms of bias and power instrumental variable method was the two stage residual inclusion method. We recommend using adaptive power calculations, updating them as refusal rates are collected in the trial recruitment phase in order to be sufficiently powered for IV analysis.

  20. Biosensors and multiple mycotoxin analysis

    NARCIS (Netherlands)

    Gaag, B. van der; Spath, S.; Dietrich, H.; Stigter, E.; Boonzaaijer, G.; Osenbruggen, T. van; Koopal, K.

    2003-01-01

    An immunochemical biosensor assay for the detection of multiple mycotoxins in a sample is described.The inhibition assay is designed to measure four different mycotoxins in a single measurement, following extraction, sample clean-up and incubation with an appropriate cocktail of anti-mycotoxin

  1. An Age-Period-Cohort Analysis

    OpenAIRE

    Ananth, Cande V.; Keyes, Katherine M.; Hamilton, Ava; Gissler, Mika; Wu, Chunsen; Liu, Shiliang; Luque-Fernandez, Miguel Angel; Skjaerven, Rolv; Williams, Michelle A.; Tikkanen, Minna; Cnattingius, Sven

    2015-01-01

    Background. Although rare, placental abruption is implicated in disproportionately high rates of perinatal morbidity and mortality. Understanding geographic and temporal variations may provide insights into possible amenable factors of abruption. We examined abruption frequencies by maternal age, delivery year, and maternal birth cohorts over three decades across seven countries. Methods. Women that delivered in the US (n = 863,879; 1979–10), Canada (4 provinces, n = 5,407,463; 1982–11), ...

  2. Multiple factor analysis by example using R

    CERN Document Server

    Pagès, Jérôme

    2014-01-01

    Multiple factor analysis (MFA) enables users to analyze tables of individuals and variables in which the variables are structured into quantitative, qualitative, or mixed groups. Written by the co-developer of this methodology, Multiple Factor Analysis by Example Using R brings together the theoretical and methodological aspects of MFA. It also includes examples of applications and details of how to implement MFA using an R package (FactoMineR).The first two chapters cover the basic factorial analysis methods of principal component analysis (PCA) and multiple correspondence analysis (MCA). The

  3. Adherence to Disease Modifying Drugs among Patients with Multiple Sclerosis in Germany: A Retrospective Cohort Study.

    Directory of Open Access Journals (Sweden)

    Kerstin Hansen

    Full Text Available Long-term therapies such as disease modifying therapy for Multiple Sclerosis (MS demand high levels of medication adherence in order to reach acceptable outcomes. The objective of this study was to describe adherence to four disease modifying drugs (DMDs among statutorily insured patients within two years following treatment initiation. These drugs were interferon beta-1a i.m. (Avonex, interferon beta-1a s.c. (Rebif, interferon beta-1b s.c. (Betaferon and glatiramer acetate s.c. (Copaxone.This retrospective cohort study used pharmacy claims data from the data warehouse of the German Institute for Drug Use Evaluation (DAPI from 2001 through 2009. New or renewed DMD prescriptions in the years 2002 to 2006 were identified and adherence was estimated during 730 days of follow-up by analyzing the medication possession ratio (MPR as proxy for compliance and persistence defined as number of days from initiation of DMD therapy until discontinuation or interruption.A total of 52,516 medication profiles or therapy cycles (11,891 Avonex, 14,060 Betaferon, 12,353 Copaxone and 14,212 Rebif from 50,057 patients were included into the analysis. Among the 4 cohorts, no clinically relevant differences were found in available covariates. The Medication Possession Ratio (MPR measured overall compliance, which was 39.9% with a threshold MPR≥0.8. There were small differences in the proportion of therapy cycles during which a patient was compliant for the following medications: Avonex (42.8%, Betaferon (40.6%, Rebif (39.2%, and Copaxone (37%. Overall persistence was 32.3% at the end of the 24 months observation period, i.e. during only one third of all included therapy cycles patients did not discontinue or interrupt DMD therapy. There were also small differences in the proportion of therapy cycles during which a patient was persistent as follows: Avonex (34.2%, Betaferon (33.4%, Rebif (31.7% and Copaxone (29.8%.Two years after initiating MS-modifying therapy, only

  4. Secondary Analysis under Cohort Sampling Designs Using Conditional Likelihood

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    Olli Saarela

    2012-01-01

    Full Text Available Under cohort sampling designs, additional covariate data are collected on cases of a specific type and a randomly selected subset of noncases, primarily for the purpose of studying associations with a time-to-event response of interest. With such data available, an interest may arise to reuse them for studying associations between the additional covariate data and a secondary non-time-to-event response variable, usually collected for the whole study cohort at the outset of the study. Following earlier literature, we refer to such a situation as secondary analysis. We outline a general conditional likelihood approach for secondary analysis under cohort sampling designs and discuss the specific situations of case-cohort and nested case-control designs. We also review alternative methods based on full likelihood and inverse probability weighting. We compare the alternative methods for secondary analysis in two simulated settings and apply them in a real-data example.

  5. Cancer risk among patients with multiple sclerosis: A cohort study in Isfahan, Iran.

    Science.gov (United States)

    Etemadifar, Masoud; Jahanbani-Ardakani, Hamidreza; Ghaffari, Sara; Fereidan-Esfahani, Maboobeh; Changaei, Hossein; Aghadoost, Nazila; Jahanbani Ardakani, Ameneh; Moradkhani, Negin

    2017-01-01

    Multiple sclerosis (MS), a central nervous system (CNS) autoimmune disorder, affects 2.3 million people around the world. Cancer kills around 7.5 million people annually. Both diseases have similar risks and intertwining molecular causes. Most studies focusing on MS and cancer have found an insignificant difference or reduction in the amount of cancer found in the MS community. We performed a cohort study using data from Isfahan Multiple Sclerosis Society (IMSS) and Isfahan cancer society and followed-up for 8 years on average (2006-2014). All of the 1718 MS patients were diagnosed according to McDonald's criteria, then standardized incidence ratio and the numbers of expected cancer case were calculated. While patients had an insignificant change in cancer prevalence, men had fewer cancer cases and women showed an increased prevalence of cancer. Certain types of cancer proved statistically significant. Breast cancer, nervous system cancers, and lymphoma were elevated in the cohort. Our results support the hypothesis that MS significantly affects certain cancers in a protective or associative manner. All cancer rates, except breast cancer, cancers located in the nervous system, and lymphomas were reduced in cohort, suggesting that unregulated immune function may provide protective effects to MS patients against cancer.

  6. Mediation Analysis with Multiple Mediators.

    Science.gov (United States)

    VanderWeele, T J; Vansteelandt, S

    2014-01-01

    Recent advances in the causal inference literature on mediation have extended traditional approaches to direct and indirect effects to settings that allow for interactions and non-linearities. In this paper, these approaches from causal inference are further extended to settings in which multiple mediators may be of interest. Two analytic approaches, one based on regression and one based on weighting are proposed to estimate the effect mediated through multiple mediators and the effects through other pathways. The approaches proposed here accommodate exposure-mediator interactions and, to a certain extent, mediator-mediator interactions as well. The methods handle binary or continuous mediators and binary, continuous or count outcomes. When the mediators affect one another, the strategy of trying to assess direct and indirect effects one mediator at a time will in general fail; the approach given in this paper can still be used. A characterization is moreover given as to when the sum of the mediated effects for multiple mediators considered separately will be equal to the mediated effect of all of the mediators considered jointly. The approach proposed in this paper is robust to unmeasured common causes of two or more mediators.

  7. Latent Variable Regression 4-Level Hierarchical Model Using Multisite Multiple-Cohorts Longitudinal Data. CRESST Report 801

    Science.gov (United States)

    Choi, Kilchan

    2011-01-01

    This report explores a new latent variable regression 4-level hierarchical model for monitoring school performance over time using multisite multiple-cohorts longitudinal data. This kind of data set has a 4-level hierarchical structure: time-series observation nested within students who are nested within different cohorts of students. These…

  8. Anti-JC virus antibody prevalence in a multinational multiple sclerosis cohort

    DEFF Research Database (Denmark)

    Olsson, Tomas; Achiron, Anat; Alfredsson, Lars

    2013-01-01

    JC virus (JCV) is an opportunistic virus known to cause progressive multifocal leukoencephalopathy. Anti-JC virus (Anti-JCV) antibody prevalence in a large, geographically diverse, multi-national multiple sclerosis (MS) cohort was compared in a cross-sectional study. Overall, anti-JCV antibody...... prevalence was 57.6%. Anti-JCV antibody prevalence in MS patients ranged from approximately 47% to 68% across these countries: Norway, 47.4%; Denmark, 52.6%; Israel, 56.6%; France, 57.6%; Italy, 58.3%; Sweden, 59.0%; Germany, 59.1%; Austria, 66.7% and Turkey, 67.7%. Prevalence increased with age (from 49...

  9. Stressful life-events in childhood and risk of multiple sclerosis: a Danish nationwide cohort study.

    Science.gov (United States)

    Nielsen, Nete Munk; Pedersen, Bo V; Stenager, Egon; Koch-Henriksen, Nils; Frisch, Morten

    2014-10-01

    Current knowledge concerning the association between exposure to stressful life-events (SFLEs) in childhood and later risk of multiple sclerosis (MS) is sparse. We studied the associations between SFLEs in childhood and subsequent risk of MS in a nationwide cohort of 2.9 million Danes born from 1968 to 2011. A SFLE in childhood was defined as exposure before age 18 years to parental divorce, parental death, or death of a sibling, using information from the Danish Civil Registration System. MS cases in the cohort were identified in the Danish Multiple Sclerosis Registry. Associations of SFLE with MS risk were evaluated by incidence rate ratios (RR) of MS obtained in log-linear Poisson regression models. Persons exposed to any SFLE in childhood were at 11% elevated risk of MS (RR = 1.11; 95% confidence interval: 1.03-1.20), compared to non-exposed persons. Stratification by subtype of SFLE showed that parental death and death of a sibling were not associated with MS risk. However, persons exposed to parental divorce were at 13% increased risk of developing MS compared to non-exposed (RR = 1.13; 1.04-1.23). Associations of SFLEs in childhood with risk of MS are weak. However, parental divorce is somehow associated with modestly increased risk of MS. © The Author(s), 2014.

  10. Age-period-cohort analysis of suicides among Japanese 1950-2003: a Bayesian cohort model analysis.

    Science.gov (United States)

    Ooe, Yosuke; Ohno, Yuko; Nakamura, Takashi

    2009-07-01

    The suicide rate in Japan is one of the highest in the world and presents us with a considerable challenge. Demographic statistics show that the number of suicides is on the rise, and at roughly 30,000 people per year have committed suicide since 1998. Suicide trends are not only related to economic boom and bust but also to certain generations and age groups. During the 1950s, there was a remarkably high suicide rate among people in their 20s, and this cohort was identical to that of the middle-age generation in the 1980s. It is important to separately understand both the trend of suicide rates and the numbers analyzed to determine the different factors that influence suicide. These include age, time period, cohort, interaction between age and time period, and changes in population composition. We performed an age-period-cohort analysis of annual trends of suicide rates by age group in Japan using a Bayesian cohort model. With the help of the Nakamura method, we have been able to break down the effects of age, time period, cohort, and the age-by-period interaction. The cohort comprised of people born in the 1930s demonstrated a relatively high suicide rate. Men currently in their 50s also belong to a high suicide rate cohort. Regarding the period effect, business cycles and by-period interaction effect, it became apparent that the high suicide rate among young adults in their early 20s around 1960 was slowing, especially among men. Instead, there was an obvious recent trend for men in their late 50s to have the highest suicide rate. This study confirmed that age-period-cohort analysis can describe these trends of suicide mortality of the Japanese.

  11. Neonatal outcomes among multiple births ≤ 32 weeks gestational age: Does mode of conception have an impact? A Cohort Study

    Directory of Open Access Journals (Sweden)

    Yoon Woojin

    2011-06-01

    Full Text Available Abstract Background Studies comparing perinatal outcomes in multiples conceived following the use of artificial reproductive technologies (ART vs. spontaneous conception (SC have reported conflicting results in terms of mortality and morbidity. Therefore, the objective of our study was to compare composite outcome of mortality and severe neonatal morbidities amongst preterm multiple births ≤ 32 weeks gestation infant born following ART vs. SC. Methods We conducted a single center cohort study at Mount Sinai Hospital, Toronto, Ontario, Canada. Data on all preterm multiple births (≤ 32 weeks GA discharged between July 2005 and June 2008 were retrospectively collected from a prospective database at our centre. Details regarding mode of conception were collected retrospectively from maternal health records. Preterm multiple births were categorized into those born following ART vs. SC. Composite outcome was defined as combination of death or any of the three neonatal morbidities (grade 3/4 intraventricular hemorrhage or periventricular leukomalacia; retinopathy of prematurity > stage 2 or chronic lung disease. Univariate and multivariate regression analysis were preformed after adjustment of confounders (maternal age, parity, triplets, gestational age, sex, and small for gestational age. Results One hundred and thirty seven neonates were born following use of ART and 233 following SC. The unadjusted composite outcome rate was significantly higher in preterm multiples born following ART vs. SC [43.1% vs. 26.6%, p = 0.001; OR 1.98 (95% CI 1.13, 3.45]; however, when adjusted for confounders the difference between groups was not statistically significant [OR 1.39, 95% CI 0.67, 2.89]. Conclusion In our population of preterm multiple births, the mode of conception had no detectable effect on the adjusted composite neonatal outcome of mortality and/or three neonatal morbidities.

  12. RAWS II: A MULTIPLE REGRESSION ANALYSIS PROGRAM,

    Science.gov (United States)

    This memorandum gives instructions for the use and operation of a revised version of RAWS, a multiple regression analysis program. The program...of preprocessed data, the directed retention of variable, listing of the matrix of the normal equations and its inverse, and the bypassing of the regression analysis to provide the input variable statistics only. (Author)

  13. Use of multiple data sources to estimate hepatitis C seroprevalence among prisoners: A retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Kathryn J Snow

    Full Text Available Hepatitis C is a major cause of preventable morbidity and mortality. Prisoners are a key population for hepatitis C control programs, and with the advent of highly effective therapies, prisons are increasingly important sites for hepatitis C diagnosis and treatment. Accurate estimates of hepatitis C prevalence among prisoners are needed in order to plan and resource service provision, however many prevalence estimates are based on surveys compromised by limited and potentially biased participation. We aimed to compare estimates derived from three different data sources, and to assess whether the use of self-report as a supplementary data source may help researchers assess the risk of selection bias. We used three data sources to estimate the prevalence of hepatitis C antibodies in a large cohort of Australian prisoners-prison medical records, self-reported status during a face-to-face interview prior to release from prison, and data from a statewide notifiable conditions surveillance system. Of 1,315 participants, 33.8% had at least one indicator of hepatitis C seropositivity, however less than one third of these (9.5% of the entire cohort were identified by all three data sources. Among participants of known status, self-report had a sensitivity of 80.1% and a positive predictive value of 97.8%. Any one data source used in isolation would have under-estimated the prevalence of hepatitis C in this cohort. Using multiple data sources in studies of hepatitis C seroprevalence among prisoners may improve case detection and help researchers assess the risk of selection bias due to non-participation in serological testing.

  14. Capturing the fragile X premutation phenotypes: a collaborative effort across multiple cohorts.

    Science.gov (United States)

    Hunter, Jessica Ezzell; Sherman, Stephanie; Grigsby, Jim; Kogan, Cary; Cornish, Kim

    2012-03-01

    To capture the neuropsychological profile among male carriers of the FMR1 premutation allele (55-200 CGG repeats) who do not meet diagnostic criteria for the late-onset fragile X-associated tremor/ataxia syndrome, FXTAS. We have initiated a multicenter collaboration that includes 3 independent cohorts, totaling 100 carriers of the premutation and 216 noncarriers. The initial focus of this collaboration has been on executive function. Four executive function scores are shared among the 3 cohorts (Controlled Oral Word Association Test, Stroop Color-Word Test, and Wechsler backward digit span and letter-number sequencing) whereas additional executive function scores are available for specific cohorts (Behavior Dyscontrol Scale, Hayling Sentence Completion Test Part B, and Wisconsin Card Sorting Test). Raw scores were analyzed by using statistical models that adjust for cohort-specific effects as well as age and education. Carriers scored significantly lower compared to noncarriers on the Stroop Color-Word Test (p = .01), Hayling Sentence Completion Test Part B (p < .01), and Behavioral Dyscontrol Scale (p = .03), with the Hayling displaying a significant age-related decline (p = .01), as assessed by an age and repeat length-group interaction. Follow-up analysis of the collective data did not identify any specific age groups or repeat length ranges (i.e., low premutation = 55-70 repeats, midpremutation = 71-100 repeats, high premutation = 101-199 repeats) that were associated with an increased risk of executive function deficits. Preliminary analyses do not indicate global executive function impairment among male carriers without FXTAS compared to noncarriers. However, impairment in inhibitory capacity may be present among a subset of carriers, though the risk factors for this group do not appear to be related to age or repeat length.

  15. System for the analysis of cohort mortality data

    International Nuclear Information System (INIS)

    McLain, R.; Frome, E.L.

    1986-01-01

    A system is developed for the analysis of cohort mortality data. This Mortality Analysis System (MAS) is designed as a research tool in epidemiologic studies. The system allows a researcher to investigate the effect of one or more factors on the mortality of a study cohort. Variables can be categorized as factors to allow for stratification in the analysis. DATA steps and PROC MATRIX are incorporated in the system to produce the output. Person-years, observed deaths, and expected deaths are calculated and cross-classified by the levels of the factors. The resulting data set can be used to compute the standardized mortality ratios (SMR) for each stratum level. Poisson regression models can then be used for further statistical analysis

  16. Multiplicative calculus in biomedical image analysis

    NARCIS (Netherlands)

    Florack, L.M.J.; Assen, van H.C.

    2011-01-01

    We advocate the use of an alternative calculus in biomedical image analysis, known as multiplicative (a.k.a. non-Newtonian) calculus. It provides a natural framework in problems in which positive images or positive definite matrix fields and positivity preserving operators are of interest. Indeed,

  17. Using Correspondence Analysis in Multiple Case Studies

    NARCIS (Netherlands)

    Kienstra, Natascha; van der Heijden, Peter G.M.

    2015-01-01

    In qualitative research of multiple case studies, Miles and Huberman proposed to summarize the separate cases in a so-called meta-matrix that consists of cases by variables. Yin discusses cross-case synthesis to study this matrix. We propose correspondence analysis (CA) as a useful tool to study

  18. Using correspondence analysis in multiple case studies

    NARCIS (Netherlands)

    Kienstra, N.H.H.; van der Heijden, P.G.M.

    2015-01-01

    In qualitative research of multiple case studies, Miles and Huberman proposed to summarize the separate cases in a so-called meta-matrix that consists of cases by variables. Yin discusses cross-case synthesis to study this matrix. We propose correspondence analysis (CA) as a useful tool to study

  19. Symptoms and personality problems before, during and after long-term psychoanalytic treatment: A multiple-cohort study

    NARCIS (Netherlands)

    Berghout, C.C.; Zevalkink, D.J.; de Jong, J.T.V.M.

    2010-01-01

    Using a multiple cohort design, we compared symptoms and personality functioning (SCL-90, BDI-II, STAI, IIP-64, MMPI-2) of patients (N= 231) in different phases of long-term psychoanalytic treatment (before, during, end, follow-up). Our results confirmed findings from earlier meta-analyses that

  20. Mortality in Danish women: age, period and cohort analysis

    DEFF Research Database (Denmark)

    Lindahl-Jacobsen, Rune

    smokers throughout their adult life, suggesting that these smoking habits may be an important factor for their increased mortality. Study aim 3 The analysis of causes of death suggested an increased risk for deaths associated with the respiratory system and from causes traditionally associated....... Conclusion This study has shown that examination of total mortality trends in relation to age, period and cohort is a powerful exploratory tool for understanding changes in mortality and thus life expectancy. The analysis of differences in mortality trends among women in Denmark, Norway and Sweden...

  1. Analysis of dynamic multiplicity fluctuations at PHOBOS

    Science.gov (United States)

    Chai, Zhengwei; PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Holynski, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J. L.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wolfs, F. L. H.; Wosiek, B.; Wozniak, K.; Wuosmaa, A. H.; Wyslouch, B.

    2005-01-01

    This paper presents the analysis of the dynamic fluctuations in the inclusive charged particle multiplicity measured by PHOBOS for Au+Au collisions at surdsNN = 200GeV within the pseudo-rapidity range of -3 < η < 3. First the definition of the fluctuations observables used in this analysis is presented, together with the discussion of their physics meaning. Then the procedure for the extraction of dynamic fluctuations is described. Some preliminary results are included to illustrate the correlation features of the fluctuation observable. New dynamic fluctuations results will be available in a later publication.

  2. Diversity Performance Analysis on Multiple HAP Networks

    Science.gov (United States)

    Dong, Feihong; Li, Min; Gong, Xiangwu; Li, Hongjun; Gao, Fengyue

    2015-01-01

    One of the main design challenges in wireless sensor networks (WSNs) is achieving a high-data-rate transmission for individual sensor devices. The high altitude platform (HAP) is an important communication relay platform for WSNs and next-generation wireless networks. Multiple-input multiple-output (MIMO) techniques provide the diversity and multiplexing gain, which can improve the network performance effectively. In this paper, a virtual MIMO (V-MIMO) model is proposed by networking multiple HAPs with the concept of multiple assets in view (MAV). In a shadowed Rician fading channel, the diversity performance is investigated. The probability density function (PDF) and cumulative distribution function (CDF) of the received signal-to-noise ratio (SNR) are derived. In addition, the average symbol error rate (ASER) with BPSK and QPSK is given for the V-MIMO model. The system capacity is studied for both perfect channel state information (CSI) and unknown CSI individually. The ergodic capacity with various SNR and Rician factors for different network configurations is also analyzed. The simulation results validate the effectiveness of the performance analysis. It is shown that the performance of the HAPs network in WSNs can be significantly improved by utilizing the MAV to achieve overlapping coverage, with the help of the V-MIMO techniques. PMID:26134102

  3. Diversity Performance Analysis on Multiple HAP Networks

    Directory of Open Access Journals (Sweden)

    Feihong Dong

    2015-06-01

    Full Text Available One of the main design challenges in wireless sensor networks (WSNs is achieving a high-data-rate transmission for individual sensor devices. The high altitude platform (HAP is an important communication relay platform for WSNs and next-generation wireless networks. Multiple-input multiple-output (MIMO techniques provide the diversity and multiplexing gain, which can improve the network performance effectively. In this paper, a virtual MIMO (V-MIMO model is proposed by networking multiple HAPs with the concept of multiple assets in view (MAV. In a shadowed Rician fading channel, the diversity performance is investigated. The probability density function (PDF and cumulative distribution function (CDF of the received signal-to-noise ratio (SNR are derived. In addition, the average symbol error rate (ASER with BPSK and QPSK is given for the V-MIMO model. The system capacity is studied for both perfect channel state information (CSI and unknown CSI individually. The ergodic capacity with various SNR and Rician factors for different network configurations is also analyzed. The simulation results validate the effectiveness of the performance analysis. It is shown that the performance of the HAPs network in WSNs can be significantly improved by utilizing the MAV to achieve overlapping coverage, with the help of the V-MIMO techniques.

  4. Benefits and challenges of using the cohort multiple randomised controlled trial design for testing an intervention for depression.

    Science.gov (United States)

    Viksveen, Petter; Relton, Clare; Nicholl, Jon

    2017-07-06

    Trials which test the effectiveness of interventions compared with the status quo frequently encounter challenges. The cohort multiple randomised controlled trial (cmRCT) design is an innovative approach to the design and conduct of pragmatic trials which seeks to address some of these challenges. In this article, we report our experiences with the first completed randomised controlled trial (RCT) using the cmRCT design. This trial-the Depression in South Yorkshire (DEPSY) trial-involved comparison of treatment as usual (TAU) with TAU plus the offer of an intervention for people with self-reported long-term moderate to severe depression. In the trial, we used an existing large population-based cohort: the Yorkshire Health Study. We discuss our experiences with recruitment, attrition, crossover, data analysis, generalisability of results, and cost. The main challenges in using the cmRCT design were the high crossover to the control group and the lower questionnaire response rate among patients who refused the offer of treatment. However, the design did help facilitate efficient and complete recruitment of the trial population as well as analysable data that were generalisable to the population of interest. Attrition rates were also smaller than those reported in other depression trials. This first completed full trial using the cmRCT design testing an intervention for self-reported depression was associated with a number of important benefits. Further research is required to compare the acceptability and cost effectiveness of standard pragmatic RCT design with the cmRCT design. ISRCTN registry: ISRCTN02484593 . Registered on 7 Jan 2013.

  5. Multiple predictor smoothing methods for sensitivity analysis

    International Nuclear Information System (INIS)

    Helton, Jon Craig; Storlie, Curtis B.

    2006-01-01

    The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described: (1) locally weighted regression (LOESS), (2) additive models, (3) projection pursuit regression, and (4) recursive partitioning regression. The indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present

  6. Multiple predictor smoothing methods for sensitivity analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Helton, Jon Craig; Storlie, Curtis B.

    2006-08-01

    The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described: (1) locally weighted regression (LOESS), (2) additive models, (3) projection pursuit regression, and (4) recursive partitioning regression. The indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present.

  7. Characteristics in childhood and adolescence associated with future multiple sclerosis risk in men: cohort study.

    Science.gov (United States)

    Gunnarsson, M; Udumyan, R; Bahmanyar, S; Nilsagård, Y; Montgomery, S

    2015-07-01

    Associations with multiple sclerosis (MS) of living conditions in childhood and characteristics in adolescence including physical fitness, cognitive function and psychological stress resilience were investigated. A cohort of male Swedish residents born 1952-1956 who were included in the Swedish Military Conscription Register was used to create a nested case-control study comprising 628 MS cases and 6187 controls matched on birth year, county of residence and vital status at time of diagnosis. Conscription examination records were linked with other national register data. Conditional logistic regression was used to evaluate associations with MS subsequent to the conscription examination. Men with MS were less likely to be from more crowded households in childhood (>two persons per room) with an adjusted odds ratio of 0.67 (95% confidence interval 0.51-0.86, P = 0.023). They had lower physical working capacity in adolescence with adjusted odds ratio of 0.94 (95% confidence interval 0.89-0.99, P = 0.026). Cognitive function and stress resilience scores displayed no significant differences between cases and controls. Parental occupation in childhood and body mass index in adolescence were not associated with future MS risk. The inverse association of MS risk with higher levels of household crowding may reflect environmental factors such as the pattern of exposure to microorganisms. Lower physical fitness in men at MS risk may indicate a protective effect of exercise or could be due to prodromal disease activity, although there was no association with cognitive function. Poor psychological stress resilience (and thus risk of chronic stress arousal) was not associated with MS. © 2015 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.

  8. Radiogenic leukemia risk analysis for the Techa River Cohort members

    International Nuclear Information System (INIS)

    Krestinina, L.Y.; Epifanova, S.B.; Akleyev, A.V.; Preston, D.; Davis, F.; Ron, E.

    2008-01-01

    Full text: Members of the Techa River Cohort have been exposed to a long-term external and internal irradiation due to releases of radioactive waste from the Mayak Production Association into the Techa River. Since internal exposure resulted primarily from incorporation of 90 Sr in the bone structure, the bone marrow was the principal target. The maximum dose to the red bone marrow accumulated over 50 years in cohort members reached 2 Gy, and the mean dose was 0.3 Gy. The epidemiological analysis of radiogenic risk of leukemia development was conducted based on the retrospective cohort study approach and regression analysis using the Epicure statistical packet. The extended Techa River Cohort (ETRC) includes about 30 thousand people of the two genders, various ages and different ethnicity (mostly Russians, Tartars and Bashkirs). The catchment area for leukemia mortality and incidence follow-up includes the whole Chelyabinsk and Kurgan Oblasts. The previous analysis of leukemia mortality risk for a 50-year follow-up period pointed out statistically significant dose dependence. The presentation will for the first time describe the results of leukemia incidence risk analyses for the period from 1953 through 2004. Over this 52-year follow-up period 92 leukemia cases (42 in men and 50 in women) were registered among ETRC members resident in the catchment area. Among those 92 cases there were 22 cases attributed to chronic lymphoid leukemia (12 in men and 10 in women). The preliminary analysis of leukemia incidence risk showed a statistically significant linear dependence on dose for total leukemias (p = 0.006), as well as for leukemias with CLL excluded (p < 0.001). The point value of the total leukemia incidence ERR was 2.0/Gy (95% CI: 0.4-15.4) and for leukemia with CLL excluded the ERR was 4.5/Gy (95% CI: 1.1-14.7). More than 57% of leukemia cases (excluding CLL) registered in ETRC members could be related to the radiogenic factor. Analyses of chronic lymphoid

  9. Clinical Features in a Danish Population-Based Cohort of Probable Multiple System Atrophy Patients

    DEFF Research Database (Denmark)

    Starhof, Charlotte; Korbo, Lise; Lassen, Christina Funch

    2016-01-01

    Background: Multiple system atrophy (MSA) is a rare, sporadic and progressive neurodegenerative disorder. We aimed to describe the clinical features of Danish probable MSA patients, evaluate their initial response to dopaminergic therapy and examine mortality. Methods: From the Danish National...... the criteria for probable MSA. We recorded clinical features, examined differences by MSA subtype and used Kaplan-Meier survival analysis to examine mortality. Results: The mean age at onset of patients with probable MSA was 60.2 years (range 36-75 years) and mean time to wheelchair dependency was 4.7 years...

  10. Exploring multiple trajectories of causality: collaboration between Anthropology and Epidemiology in the 1982 birth cohort, Pelotas, Southern Brazil

    Science.gov (United States)

    Béhague, Dominique P; Gonçalves, Helen

    2009-01-01

    OBJECTIVE: Although the relationship between epidemiology and anthropology has a long history, it has generally been comprised of the integration of quantitative and qualitative methods. Only recently have the two fields begun to converge along theoretical lines, leading to a growing mutual interest in explaining rather than simply describing phenomena. This paper aimed to illustrate how ethnographic analyses can be used to assist with the in-depth and theoretically-imbued interpretation of epidemiological results. METHODS: The anthropological analysis presented in this paper used ethnographic data collected as part of the ongoing 1982 birth cohort study, between 1997 and 2007 in Pelotas, Southern Brazil. Analyses were framed according to the results presented in two of the epidemiological articles published in this series on the determinants of mental morbidity and age of sexual initiation. RESULTS AND CONCLUSIONS: The ethnographic results show that statistical associations consist of multiple pathways of influence and causality that generally correspond to the unique experiences of specific subgroups. In exploring these pathways, the paper highlights the importance of an additional set of mediating factors that account for epidemiological results; these include the awareness and experience of inequities, the role of violence in everyday life, traumatic life events, increasing social isolation and emotional introversion as a response to life's difficulties, and differing approaches towards socio-psychological maturation. Theoretical and methodological collaboration between anthropology and epidemiology is important for public health, as it has positively modified both fields. PMID:19142353

  11. [Exploring multiple trajectories of causality: collaboration between Anthropology and Epidemiology in the 1982 birth cohort, Pelotas, Southern Brazil].

    Science.gov (United States)

    Béhague, Dominique P; Gonçalves, Helen

    2008-12-01

    Although the relationship between epidemiology and anthropology has a long history, it has generally been comprised of the integration of quantitative and qualitative methods. Only recently have the two fields begun to converge along theoretical lines, leading to a growing mutual interest in explaining rather than simply describing phenomena. This paper aimed to illustrate how ethnographic analyses can be used to assist with the in-depth and theoretically-imbued interpretation of epidemiological results. The anthropological analysis presented in this paper used ethnographic data collected as part of the ongoing 1982 birth cohort study, between 1997 and 2007 in Pelotas, Southern Brazil. Analyses were framed according to the results presented in two of the epidemiological articles published in this series on the determinants of mental morbidity and age of sexual initiation. The ethnographic results show that statistical associations consist of multiple pathways of influence and causality that generally correspond to the unique experiences of specific subgroups. In exploring these pathways, the paper highlights the importance of an additional set of mediating factors that account for epidemiological results; these include the awareness and experience of inequities, the role of violence in everyday life, traumatic life events, increasing social isolation and emotional introversion as a response to life's difficulties, and differing approaches towards socio-psychological maturation. Theoretical and methodological collaboration between anthropology and epidemiology is important for public health, as it has positively modified both fields.

  12. Structural model analysis of multiple quantitative traits.

    Directory of Open Access Journals (Sweden)

    Renhua Li

    2006-07-01

    Full Text Available We introduce a method for the analysis of multilocus, multitrait genetic data that provides an intuitive and precise characterization of genetic architecture. We show that it is possible to infer the magnitude and direction of causal relationships among multiple correlated phenotypes and illustrate the technique using body composition and bone density data from mouse intercross populations. Using these techniques we are able to distinguish genetic loci that affect adiposity from those that affect overall body size and thus reveal a shortcoming of standardized measures such as body mass index that are widely used in obesity research. The identification of causal networks sheds light on the nature of genetic heterogeneity and pleiotropy in complex genetic systems.

  13. Validating predictors of disease progression in a large cohort of primary-progressive multiple sclerosis based on a systematic literature review.

    Directory of Open Access Journals (Sweden)

    Jan-Patrick Stellmann

    Full Text Available New agents with neuroprotective or neuroregenerative potential might be explored in primary-progressive Multiple Sclerosis (PPMS--the MS disease course with leading neurodegenerative pathology. Identification of patients with a high short-term risk for progression may minimize study duration and sample size. Cohort studies reported several variables as predictors of EDSS disability progression but findings were partially contradictory.To analyse the impact of published predictors on EDSS disease progression in a large cohort of PPMS patients.A systematic literature research was performed to identify predictors for disease progression in PPMS. Individual case data from the Sylvia Lawry Centre (SLC and the Hamburg MS patient database (HAPIMS was pooled for a retrospective validation of these predictors on the annualized EDSS change.The systematic literature analysis revealed heterogeneous data from 3 prospective and 5 retrospective natural history cohort studies. Age at onset, gender, type of first symptoms and early EDSS changes were available for validation. Our pooled cohort of 597 PPMS patients (54% female had a mean follow-up of 4.4 years and mean change of EDSS of 0.35 per year based on 2503 EDSS assessments. There was no significant association between the investigated variables and the EDSS-change.None of the analysed variables were predictive for the disease progression measured by the annualized EDSS change. Whether PPMS is still unpredictable or our results may be due to limitations of cohort assessments or selection of predictors cannot be answered. Large systematic prospective studies with new endpoints are needed.

  14. Influence of birth cohort on age of onset cluster analysis in bipolar I disorder

    DEFF Research Database (Denmark)

    Bauer, M; Glenn, T; Alda, M

    2015-01-01

    Purpose: Two common approaches to identify subgroups of patients with bipolar disorder are clustering methodology (mixture analysis) based on the age of onset, and a birth cohort analysis. This study investigates if a birth cohort effect will influence the results of clustering on the age of onset...... cohort. Model-based clustering (mixture analysis) was then performed on the age of onset data using the residuals. Clinical variables in subgroups were compared. Results: There was a strong birth cohort effect. Without adjusting for the birth cohort, three subgroups were found by clustering. After...... on the age of onset, and that there is a birth cohort effect. Including the birth cohort adjustment altered the number and characteristics of subgroups detected when clustering by age of onset. Further investigation is needed to determine if combining both approaches will identify subgroups that are more...

  15. Flexible Mediation Analysis With Multiple Mediators.

    Science.gov (United States)

    Steen, Johan; Loeys, Tom; Moerkerke, Beatrijs; Vansteelandt, Stijn

    2017-07-15

    The advent of counterfactual-based mediation analysis has triggered enormous progress on how, and under what assumptions, one may disentangle path-specific effects upon combining arbitrary (possibly nonlinear) models for mediator and outcome. However, current developments have largely focused on single mediators because required identification assumptions prohibit simple extensions to settings with multiple mediators that may depend on one another. In this article, we propose a procedure for obtaining fine-grained decompositions that may still be recovered from observed data in such complex settings. We first show that existing analytical approaches target specific instances of a more general set of decompositions and may therefore fail to provide a comprehensive assessment of the processes that underpin cause-effect relationships between exposure and outcome. We then outline conditions for obtaining the remaining set of decompositions. Because the number of targeted decompositions increases rapidly with the number of mediators, we introduce natural effects models along with estimation methods that allow for flexible and parsimonious modeling. Our procedure can easily be implemented using off-the-shelf software and is illustrated using a reanalysis of the World Health Organization's Large Analysis and Review of European Housing and Health Status (WHO-LARES) study on the effect of mold exposure on mental health (2002-2003). © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Causal mediation analysis with multiple mediators.

    Science.gov (United States)

    Daniel, R M; De Stavola, B L; Cousens, S N; Vansteelandt, S

    2015-03-01

    In diverse fields of empirical research-including many in the biological sciences-attempts are made to decompose the effect of an exposure on an outcome into its effects via a number of different pathways. For example, we may wish to separate the effect of heavy alcohol consumption on systolic blood pressure (SBP) into effects via body mass index (BMI), via gamma-glutamyl transpeptidase (GGT), and via other pathways. Much progress has been made, mainly due to contributions from the field of causal inference, in understanding the precise nature of statistical estimands that capture such intuitive effects, the assumptions under which they can be identified, and statistical methods for doing so. These contributions have focused almost entirely on settings with a single mediator, or a set of mediators considered en bloc; in many applications, however, researchers attempt a much more ambitious decomposition into numerous path-specific effects through many mediators. In this article, we give counterfactual definitions of such path-specific estimands in settings with multiple mediators, when earlier mediators may affect later ones, showing that there are many ways in which decomposition can be done. We discuss the strong assumptions under which the effects are identified, suggesting a sensitivity analysis approach when a particular subset of the assumptions cannot be justified. These ideas are illustrated using data on alcohol consumption, SBP, BMI, and GGT from the Izhevsk Family Study. We aim to bridge the gap from "single mediator theory" to "multiple mediator practice," highlighting the ambitious nature of this endeavor and giving practical suggestions on how to proceed. © 2014 The Authors Biometrics published by Wiley Periodicals, Inc. on behalf of International Biometric Society.

  17. Head injury is not a risk factor for multiple sclerosis: a prospective cohort study

    DEFF Research Database (Denmark)

    Pfleger, C C H; Koch-Henriksen, N; Stenager, E

    2009-01-01

    or to be refuted conclusively. OBJECTIVE: To determine whether head trauma is associated with an increased risk of developing MS. METHOD: A cohort of 150,868 subjects, 95,111 men, and 55,757 women registered in the National Danish Patient Registry with hospital admission for cerebral concussion, contusion...

  18. Long-term persistence with injectable therapy in relapsing-remitting multiple sclerosis: an 18-year observational cohort study.

    Directory of Open Access Journals (Sweden)

    Simon Zhornitsky

    Full Text Available Disease modifying therapies (DMTs reduce the frequency of relapses and accumulation of disability in multiple sclerosis (MS. Long-term persistence with treatment is important to optimize treatment benefit. This long-term, cohort study was conducted at the Calgary MS Clinic. All consenting adults with relapsing-remitting MS who started either glatiramer acetate (GA or interferon-β 1a/1b (IFN-β between January 1st, 1996 and July 1st, 2011 were included. Follow-up continued to February 1st, 2014. Time-to-discontinuation of the initial and subsequently-prescribed DMTs (switches was analysed using Kaplan-Meier survival analyses. Group differences were compared using log-rank tests and multivariable Cox regression models. Analysis included 1471 participants; 906 were initially prescribed GA and 565 were initially prescribed IFN-β. Follow-up information was available for 87%; 29 (2% were lost to follow-up and 160 (11% moved from Southern Alberta while still using DMT. Median time-to-discontinuation of all injectable DMTs was 11.1 years. Participants with greater disability at treatment initiation, those who started treatment before age 30, and those who started between 2006 and 2011 were more likely to discontinue use of all injectable DMTs. Median time-to-discontinuation of the initial DMT was 8.6 years. Those initially prescribed GA remained on treatment longer. Of 610 participants who discontinued injectable DMT, 331 (54% started an oral DMT, or a second-line DMT, or resumed injectable DMT after 90 days. Persistence with injectable DMTs was high in this long-term population-based study. Most participants who discontinued injectable DMT did not remain untreated. Further research is required to understand treatment outcomes and outcomes after stopping DMT.

  19. Treatment effectiveness of alemtuzumab compared with natalizumab, fingolimod, and interferon beta in relapsing-remitting multiple sclerosis: a cohort study.

    Science.gov (United States)

    Kalincik, Tomas; Brown, J William L; Robertson, Neil; Willis, Mark; Scolding, Neil; Rice, Claire M; Wilkins, Alastair; Pearson, Owen; Ziemssen, Tjalf; Hutchinson, Michael; McGuigan, Christopher; Jokubaitis, Vilija; Spelman, Tim; Horakova, Dana; Havrdova, Eva; Trojano, Maria; Izquierdo, Guillermo; Lugaresi, Alessandra; Prat, Alexandre; Girard, Marc; Duquette, Pierre; Grammond, Pierre; Alroughani, Raed; Pucci, Eugenio; Sola, Patrizia; Hupperts, Raymond; Lechner-Scott, Jeannette; Terzi, Murat; Van Pesch, Vincent; Rozsa, Csilla; Grand'Maison, François; Boz, Cavit; Granella, Franco; Slee, Mark; Spitaleri, Daniele; Olascoaga, Javier; Bergamaschi, Roberto; Verheul, Freek; Vucic, Steve; McCombe, Pamela; Hodgkinson, Suzanne; Sanchez-Menoyo, Jose Luis; Ampapa, Radek; Simo, Magdolna; Csepany, Tunde; Ramo, Cristina; Cristiano, Edgardo; Barnett, Michael; Butzkueven, Helmut; Coles, Alasdair

    2017-04-01

    Alemtuzumab, an anti-CD52 antibody, is proven to be more efficacious than interferon beta-1a in the treatment of relapsing-remitting multiple sclerosis, but its efficacy relative to more potent immunotherapies is unknown. We compared the effectiveness of alemtuzumab with natalizumab, fingolimod, and interferon beta in patients with relapsing-remitting multiple sclerosis treated for up to 5 years. In this international cohort study, we used data from propensity-matched patients with relapsing-remitting multiple sclerosis from the MSBase and six other cohorts. Longitudinal clinical data were obtained from 71 MSBase centres in 21 countries and from six non-MSBase centres in the UK and Germany between Nov 1, 2015, and June 30, 2016. Key inclusion criteria were a diagnosis of definite relapsing-remitting multiple sclerosis, exposure to one of the study therapies (alemtuzumab, interferon beta, fingolimod, or natalizumab), age 65 years or younger, Expanded Disability Status Scale (EDSS) score 6·5 or lower, and no more than 10 years since the first multiple sclerosis symptom. The primary endpoint was annualised relapse rate. The secondary endpoints were cumulative hazards of relapses, disability accumulation, and disability improvement events. We compared relapse rates with negative binomial models, and estimated cumulative hazards with conditional proportional hazards models. Patients were treated between Aug 1, 1994, and June 30, 2016. The cohorts consisted of 189 patients given alemtuzumab, 2155 patients given interferon beta, 828 patients given fingolimod, and 1160 patients given natalizumab. Alemtuzumab was associated with a lower annualised relapse rate than interferon beta (0·19 [95% CI 0·14-0·23] vs 0·53 [0·46-0·61], pmultiple sclerosis. Alemtuzumab seems superior to fingolimod and interferon beta in mitigating relapse activity. Natalizumab seems superior to alemtuzumab in enabling recovery from disability. Both natalizumab and alemtuzumab seem highly

  20. Variable precision rough set for multiple decision attribute analysis

    Institute of Scientific and Technical Information of China (English)

    Lai; Kin; Keung

    2008-01-01

    A variable precision rough set (VPRS) model is used to solve the multi-attribute decision analysis (MADA) problem with multiple conflicting decision attributes and multiple condition attributes. By introducing confidence measures and a β-reduct, the VPRS model can rationally solve the conflicting decision analysis problem with multiple decision attributes and multiple condition attributes. For illustration, a medical diagnosis example is utilized to show the feasibility of the VPRS model in solving the MADA...

  1. A cohort analysis of nuclear generation cost data

    International Nuclear Information System (INIS)

    Ono, Kenji; Nakamura, Takashi

    2002-01-01

    At the Nuclear Energy Information Center of the Central Research Institute of Electric Power Industry, Ltd., cost analysis of nuclear power generation has been carried out. In general, it is frequently carried out to analyze timely changing trends on various indexes on management of power stations such as annual O and M (operation and management) costs, apparatus using ratio, and so on, in nuclear power stations. Main aims of such analyses are to obtain knowledge useful for future policies and management decision making by grasping factors causing such changes to evaluate effects based on them as quantitatively as possible. Effects of the timely changing factors on various indexes on management of power stations can consider by dividing them to three types shown as follows; (1) effects of every years, (2) effects of every elapsed years, and (3) effects of operation beginning year. By separating these three effects to evaluate them, grasping of factors at background of the changes and their quantitative evaluations can be carried out more correctly, to be expected to obtain more useful knowledge. Here were described results applied on engineering method called by the 'Bayes type Cohort model' developed at a field of social science to trend analysis on indexes of such power stations. (G.K.)

  2. Signatures of inflammation and impending multiple organ dysfunction in the hyperacute phase of trauma: A prospective cohort study.

    Science.gov (United States)

    Cabrera, Claudia P; Manson, Joanna; Shepherd, Joanna M; Torrance, Hew D; Watson, David; Longhi, M Paula; Hoti, Mimoza; Patel, Minal B; O'Dwyer, Michael; Nourshargh, Sussan; Pennington, Daniel J; Barnes, Michael R; Brohi, Karim

    2017-07-01

    Severe trauma induces a widespread response of the immune system. This "genomic storm" can lead to poor outcomes, including Multiple Organ Dysfunction Syndrome (MODS). MODS carries a high mortality and morbidity rate and adversely affects long-term health outcomes. Contemporary management of MODS is entirely supportive, and no specific therapeutics have been shown to be effective in reducing incidence or severity. The pathogenesis of MODS remains unclear, and several models are proposed, such as excessive inflammation, a second-hit insult, or an imbalance between pro- and anti-inflammatory pathways. We postulated that the hyperacute window after trauma may hold the key to understanding how the genomic storm is initiated and may lead to a new understanding of the pathogenesis of MODS. We performed whole blood transcriptome and flow cytometry analyses on a total of 70 critically injured patients (Injury Severity Score [ISS] ≥ 25) at The Royal London Hospital in the hyperacute time period within 2 hours of injury. We compared transcriptome findings in 36 critically injured patients with those of 6 patients with minor injuries (ISS ≤ 4). We then performed flow cytometry analyses in 34 critically injured patients and compared findings with those of 9 healthy volunteers. Immediately after injury, only 1,239 gene transcripts (4%) were differentially expressed in critically injured patients. By 24 hours after injury, 6,294 transcripts (21%) were differentially expressed compared to the hyperacute window. Only 202 (16%) genes differentially expressed in the hyperacute window were still expressed in the same direction at 24 hours postinjury. Pathway analysis showed principally up-regulation of pattern recognition and innate inflammatory pathways, with down-regulation of adaptive responses. Immune deconvolution, flow cytometry, and modular analysis suggested a central role for neutrophils and Natural Killer (NK) cells, with underexpression of T- and B cell responses. In

  3. Signatures of inflammation and impending multiple organ dysfunction in the hyperacute phase of trauma: A prospective cohort study.

    Directory of Open Access Journals (Sweden)

    Claudia P Cabrera

    2017-07-01

    Full Text Available Severe trauma induces a widespread response of the immune system. This "genomic storm" can lead to poor outcomes, including Multiple Organ Dysfunction Syndrome (MODS. MODS carries a high mortality and morbidity rate and adversely affects long-term health outcomes. Contemporary management of MODS is entirely supportive, and no specific therapeutics have been shown to be effective in reducing incidence or severity. The pathogenesis of MODS remains unclear, and several models are proposed, such as excessive inflammation, a second-hit insult, or an imbalance between pro- and anti-inflammatory pathways. We postulated that the hyperacute window after trauma may hold the key to understanding how the genomic storm is initiated and may lead to a new understanding of the pathogenesis of MODS.We performed whole blood transcriptome and flow cytometry analyses on a total of 70 critically injured patients (Injury Severity Score [ISS] ≥ 25 at The Royal London Hospital in the hyperacute time period within 2 hours of injury. We compared transcriptome findings in 36 critically injured patients with those of 6 patients with minor injuries (ISS ≤ 4. We then performed flow cytometry analyses in 34 critically injured patients and compared findings with those of 9 healthy volunteers. Immediately after injury, only 1,239 gene transcripts (4% were differentially expressed in critically injured patients. By 24 hours after injury, 6,294 transcripts (21% were differentially expressed compared to the hyperacute window. Only 202 (16% genes differentially expressed in the hyperacute window were still expressed in the same direction at 24 hours postinjury. Pathway analysis showed principally up-regulation of pattern recognition and innate inflammatory pathways, with down-regulation of adaptive responses. Immune deconvolution, flow cytometry, and modular analysis suggested a central role for neutrophils and Natural Killer (NK cells, with underexpression of T- and B cell

  4. Prognostic Classification Factors Associated With Development of Multiple Autoantibodies, Dysglycemia, and Type 1 Diabetes?A Recursive Partitioning Analysis

    OpenAIRE

    Xu, Ping; Krischer, Jeffrey P.

    2016-01-01

    OBJECTIVE To define prognostic classification factors associated with the progression from single to multiple autoantibodies, multiple autoantibodies to dysglycemia, and dysglycemia to type 1 diabetes onset in relatives of individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS Three distinct cohorts of subjects from the Type 1 Diabetes TrialNet Pathway to Prevention Study were investigated separately. A recursive partitioning analysis (RPA) was used to determine the risk classes. Clini...

  5. Association analysis of multiple traits by an approach of combining ...

    Indian Academy of Sciences (India)

    Lili Chen

    diseases. Joint analysis of multiple traits can increase statistical power of association analysis and uncover the underlying genetic ... genthaler and Thilly 2007), the combined multivariate and ... Because of using reverse regression model, our.

  6. Mortality in former Olympic athletes: retrospective cohort analysis

    Science.gov (United States)

    Zwiers, R; Zantvoord, F W A; van Bodegom, D; van der Ouderaa, F J G; Westendorp, R G J

    2012-01-01

    Objective To assess the mortality risk in subsequent years (adjusted for year of birth, nationality, and sex) of former Olympic athletes from disciplines with different levels of exercise intensity. Design Retrospective cohort study. Setting Former Olympic athletes. Participants 9889 athletes (with a known age at death) who participated in the Olympic Games between 1896 and 1936, representing 43 types of disciplines with different levels of cardiovascular, static, and dynamic intensity exercise; high or low risk of bodily collision; and different levels of physical contact. Main outcome measure All cause mortality. Results Hazard ratios for mortality among athletes from disciplines with moderate cardiovascular intensity (1.01, 95% confidence interval 0.96 to 1.07) or high cardiovascular intensity (0.98, 0.92 to 1.04) were similar to those in athletes from disciplines with low cardiovascular intensity. The underlying static and dynamic components in exercise intensity showed similar non-significant results. Increased mortality was seen among athletes from disciplines with a high risk of bodily collision (hazard ratio 1.11, 1.06 to 1.15) and with high levels of physical contact (1.16, 1.11 to 1.22). In a multivariate analysis, the effect of high cardiovascular intensity remained similar (hazard ratio 1.05, 0.89 to 1.25); the increased mortality associated with high physical contact persisted (hazard ratio 1.13, 1.06 to 1.21), but that for bodily collision became non-significant (1.03, 0.98 to 1.09) as a consequence of its close relation with physical contact. Conclusions Among former Olympic athletes, engagement in disciplines with high intensity exercise did not bring a survival benefit compared with disciplines with low intensity exercise. Those who engaged in disciplines with high levels of physical contact had higher mortality than other Olympians later in life. PMID:23241269

  7. Simultaneous Two-Way Clustering of Multiple Correspondence Analysis

    Science.gov (United States)

    Hwang, Heungsun; Dillon, William R.

    2010-01-01

    A 2-way clustering approach to multiple correspondence analysis is proposed to account for cluster-level heterogeneity of both respondents and variable categories in multivariate categorical data. Specifically, in the proposed method, multiple correspondence analysis is combined with k-means in a unified framework in which "k"-means is…

  8. Spacecraft Multiple Array Communication System Performance Analysis

    Science.gov (United States)

    Hwu, Shian U.; Desilva, Kanishka; Sham, Catherine C.

    2010-01-01

    The Communication Systems Simulation Laboratory (CSSL) at the NASA Johnson Space Center is tasked to perform spacecraft and ground network communication system simulations, design validation, and performance verification. The CSSL has developed simulation tools that model spacecraft communication systems and the space and ground environment in which the tools operate. In this paper, a spacecraft communication system with multiple arrays is simulated. Multiple array combined technique is used to increase the radio frequency coverage and data rate performance. The technique is to achieve phase coherence among the phased arrays to combine the signals at the targeting receiver constructively. There are many technical challenges in spacecraft integration with a high transmit power communication system. The array combining technique can improve the communication system data rate and coverage performances without increasing the system transmit power requirements. Example simulation results indicate significant performance improvement can be achieved with phase coherence implementation.

  9. The Pregnancy Exposome: Multiple Environmental Exposures in the INMA-Sabadell Birth Cohort.

    Science.gov (United States)

    Robinson, Oliver; Basagaña, Xavier; Agier, Lydiane; de Castro, Montserrat; Hernandez-Ferrer, Carles; Gonzalez, Juan R; Grimalt, Joan O; Nieuwenhuijsen, Mark; Sunyer, Jordi; Slama, Rémy; Vrijheid, Martine

    2015-09-01

    The "exposome" is defined as "the totality of human environmental exposures from conception onward, complementing the genome" and its holistic approach may advance understanding of disease etiology. We aimed to describe the correlation structure of the exposome during pregnancy to better understand the relationships between and within families of exposure and to develop analytical tools appropriate to exposome data. Estimates on 81 environmental exposures of current health concern were obtained for 728 women enrolled in The INMA (INfancia y Medio Ambiente) birth cohort, in Sabadell, Spain, using biomonitoring, geospatial modeling, remote sensors, and questionnaires. Pair-wise Pearson's and polychoric correlations were calculated and principal components were derived. The median absolute correlation across all exposures was 0.06 (5th-95th centiles, 0.01-0.54). There were strong levels of correlation within families of exposure (median = 0.45, 5th-95th centiles, 0.07-0.85). Nine exposures (11%) had a correlation higher than 0.5 with at least one exposure outside their exposure family. Effectively all the variance in the data set (99.5%) was explained by 40 principal components. Future exposome studies should interpret exposure effects in light of their correlations to other exposures. The weak to moderate correlation observed between exposure families will permit adjustment for confounding in future exposome studies.

  10. Seismic analysis of piping systems subjected to multiple support excitations

    International Nuclear Information System (INIS)

    Sundararajan, C.; Vaish, A.K.; Slagis, G.C.

    1981-01-01

    The paper presents the results of a comparative study between the multiple response spectrum method and the time-history method for the seismic analysis of nuclear piping systems subjected to different excitation at different supports or support groups. First, the necessary equations for the above analysis procedures are derived. Then, three actual nuclear piping systems subjected to single and multiple excitations are analyzed by the different methods, and extensive comparisons of the results (stresses) are made. Based on the results, it is concluded that the multiple response spectrum analysis gives acceptable results as compared to the ''exact'', but much more costly, time-history analysis. 6 refs

  11. Findings of multiple HPV genotypes in cervical carcinoma are associated with poor cancer-specific survival in a Swedish cohort of cervical cancer primarily treated with radiotherapy.

    Science.gov (United States)

    Kaliff, Malin; Sorbe, Bengt; Mordhorst, Louise Bohr; Helenius, Gisela; Karlsson, Mats G; Lillsunde-Larsson, Gabriella

    2018-04-10

    Cervical cancer (CC) is one of the most common cancers in women and virtually all cases of CC are a result of a persistent infection of human papillomavirus (HPV). For disease detected in early stages there is curing treatment but when diagnosed late with recurring disease and metastasis there are limited possibilities. Here we evaluate HPV impact on treatment resistance and metastatic disease progression. Prevalence and distribution of HPV genotypes and HPV16 variants in a Swedish CC patient cohort (n=209) was evaluated, as well as HPV influence on patient prognosis. Tumor samples suitable for analysis (n=204) were genotyped using two different real-time PCR methods. HPV16 variant analysis was made using pyrosequencing. Results showed that HPV prevalence in the total series was 93%. Of the HPV-positive samples, 13% contained multiple infections, typically with two high-risk HPV together. Primary cure rate for the complete series was 95%. Recurrence rate of the complete series was 28% and distant recurrences were most frequent (20%). Patients with tumors containing multiple HPV-strains and particularly HPV genotypes belonging to the alpha 7 and 9 species together had a significantly higher rate of distant tumor recurrences and worse cancer-specific survival rate.

  12. The socioeconomic profile of a Barrett's oesophagus cohort assessed by the 2010 Index of Multiple Deprivation.

    Science.gov (United States)

    Bhattacharjee, Santanu; Caygill, Christine P J; Charlett, Andre; Fox, Anthony J; Gatenby, Piers A C; Watson, Anthony; Royston, Christine; Bardhan, Karna D

    2016-02-01

    Several reports have described the relationship between socioeconomic status and oesophageal adenocarcinoma but only one with its precursor condition, Barrett's oesophagus. We therefore investigated such an association. The majority (88%) of patients diagnosed with Barrett's at Rotherham District General Hospital between 28 April 1978 and 31 August 2012 consented to inclusion in the UK Barrett's Oesophagus Registry. Those residing within Rotherham form the basis of this study. We assessed socioeconomic status using the Index of Multiple Deprivation 2010 scores which can be assigned to every English postcode. The scores for the whole of England were divided into five equal groups; those of the 6257 postcodes within Rotherham (including those of Barrett's patients) were compared against the national quintile relevant to their score. We examined the ratio of observed against expected numbers of Barrett's in each quintile before and since 2001, the median year of diagnosis. The study group comprised 1076 patients with Barrett's oesophagus. Before 2001 their distribution across the deprivation quintiles was similar to that expected. Since then it has changed significantly, with 37% more Barrett's patients than expected among the two least deprived quintiles, but 11% fewer than expected in the larger population comprising the two most deprived quintiles (P=0.0001). There was no significant difference in the distribution of sex (P=0.27), nor the mean age at diagnosis between the two time periods (P=0.92). Since 2001, there has been a major change in the distribution of Barrett's in relation to socioeconomic status, measured by the Index of Multiple Deprivation.

  13. Educational expansion and the education gradient in health: A hierarchical age-period-cohort analysis.

    Science.gov (United States)

    Delaruelle, Katrijn; Buffel, Veerle; Bracke, Piet

    2015-11-01

    Researchers have recently been investigating the temporal variation in the educational gradient in health. While there is abundant literature concerning age trajectories, theoretical knowledge about cohort differences is relatively limited. Therefore, in analogy with the life course perspective, we introduce two contrasting cohort-specific hypotheses. The diminishing health returns hypothesis predicts a decrease in educational disparities in health across cohorts. By contrast, the cohort accretion hypothesis suggests that the education-health gap will be more pronounced among younger cohorts. To shed light on this, we perform a hierarchical age-period-cohort analysis (HAPC), using data from a subsample of individuals between 25 and 85 years of age (N = 232,573) from 32 countries in the European Social Survey (six waves: 2002-2012). The analysis leads to three important conclusions. First, we observe a widening health gap between different educational levels over the life course. Second, we find that these educational differences in the age trajectories of health seem to strengthen with each successive birth cohort. However, the two age-related effects disappear when we control for employment status, household income, and family characteristics. Last, when adjusting for these mediators, we reveal evidence to support the diminishing health returns hypothesis, implying that it is primarily the direct association between education and health that decreases across cohorts. This finding raises concerns about potential barriers to education being a vehicle for empowerment and the promotion of health. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Multiple sclerosis susceptibility-associated SNPs do not influence disease severity measures in a cohort of Australian MS patients.

    Directory of Open Access Journals (Sweden)

    Cathy J Jensen

    Full Text Available Recent association studies in multiple sclerosis (MS have identified and replicated several single nucleotide polymorphism (SNP susceptibility loci including CLEC16A, IL2RA, IL7R, RPL5, CD58, CD40 and chromosome 12q13-14 in addition to the well established allele HLA-DR15. There is potential that these genetic susceptibility factors could also modulate MS disease severity, as demonstrated previously for the MS risk allele HLA-DR15. We investigated this hypothesis in a cohort of 1006 well characterised MS patients from South-Eastern Australia. We tested the MS-associated SNPs for association with five measures of disease severity incorporating disability, age of onset, cognition and brain atrophy. We observed trends towards association between the RPL5 risk SNP and time between first demyelinating event and relapse, and between the CD40 risk SNP and symbol digit test score. No associations were significant after correction for multiple testing. We found no evidence for the hypothesis that these new MS disease risk-associated SNPs influence disease severity.

  15. A Signal Detection Approach in a Multiple Cohort Study: Different Admission Tools Uniquely Select Different Successful Students

    Directory of Open Access Journals (Sweden)

    Linda van Ooijen-van der Linden

    2018-05-01

    Full Text Available Using multiple admission tools in university admission procedures is common practice. This is particularly useful if different admission tools uniquely select different subgroups of students who will be successful in university programs. A signal-detection approach was used to investigate the accuracy of Secondary School grade point average (SSGPA, an admission test score (ACS, and a non-cognitive score (NCS in uniquely selecting successful students. This was done for three consecutive first year cohorts of a broad psychology program. Each applicant's score on SSGPA, ACS, or NCS alone—and on seven combinations of these scores, all considered separate “admission tools”—was compared at two different (medium and high cut-off scores (criterion levels. Each of the tools selected successful students who were not selected by any of the other tools. Both sensitivity and specificity were enhanced by implementing multiple tools. The signal-detection approach distinctively provided useful information for decisions on admission instruments and cut-off scores.

  16. Failure analysis of multiple delaminated composite plates due

    Indian Academy of Sciences (India)

    The present work aims at the first ply failure analysis of laminated composite plates with arbitrarily located multiple delaminations subjected to transverse static load as well as impact. The theoretical formulation is based on a simple multiple delamination model. Conventional first order shear deformation is assumed using ...

  17. Using module analysis for multiple choice responses

    DEFF Research Database (Denmark)

    Brewe, Eric; Bruun, Jesper; Bearden, Ian

    2016-01-01

    We describe a methodology for carrying out a network analysis of Force Concept Inventory (FCI) responses that aims to identify communities of incorrect responses. This method first treats FCI responses as a bipartite, student X response, network. We then use Locally Adaptive Network Sparsificatio...

  18. A concise revised myeloma comorbidity index as a valid prognostic instrument in a large cohort of 801 multiple myeloma patients

    NARCIS (Netherlands)

    M. Engelhardt (Monika); Domm, A.-S. (Anne-Saskia); Dold, S.M. (Sandra Maria); G. Ihorst (Gabriele); Reinhardt, H. (Heike); Zober, A. (Alexander); Hieke, S. (Stefanie); Baayen, C. (Corine); Müller, S.J. (Stefan Jürgen); H. Einsele (Hermann); P. Sonneveld (Pieter); O. Landgren; M. Schumacher (M.); R. Wäsch (Ralph)

    2017-01-01

    textabstractWith growing numbers of elderly multiple myeloma patients, reliable tools to assess their vulnerability are required. The objective of the analysis herein was to develop and validate an easy to use myeloma risk score (revised Myeloma Comorbidity Index) that allows for risk prediction of

  19. The marriage boom and marriage bust in the United States: An age-period-cohort analysis.

    Science.gov (United States)

    Schellekens, Jona

    2017-03-01

    In the 1950s and 1960s there was an unprecedented marriage boom in the United States. This was followed in the 1970s by a marriage bust. Some argue that both phenomena are cohort effects, while others argue that they are period effects. The study reported here tested the major period and cohort theories of the marriage boom and bust, by estimating an age-period-cohort model of first marriage for the years 1925-79 using census microdata. The results of the analysis indicate that the marriage boom was mostly a period effect, although there were also cohort influences. More specifically, the hypothesis that the marriage boom was mostly a response to rising wages is shown to be consistent with the data. However, much of the marriage bust can be accounted for by unidentified cohort influences, at least until 1980.

  20. Dimensions of cultural consumption among tourists : Multiple correspondence analysis

    NARCIS (Netherlands)

    Richards, G.W.; van der Ark, L.A.

    2013-01-01

    The cultural tourism market has diversified and fragmented into many different niches. Previous attempts to segment cultural tourists have been largely unidimensional, failing to capture the complexity of cultural production and consumption. We employ multiple correspondence analysis to visualize

  1. Approaches to data analysis of multiple-choice questions

    OpenAIRE

    Lin Ding; Robert Beichner

    2009-01-01

    This paper introduces five commonly used approaches to analyzing multiple-choice test data. They are classical test theory, factor analysis, cluster analysis, item response theory, and model analysis. Brief descriptions of the goals and algorithms of these approaches are provided, together with examples illustrating their applications in physics education research. We minimize mathematics, instead placing emphasis on data interpretation using these approaches.

  2. Approaches to Data Analysis of Multiple-Choice Questions

    Science.gov (United States)

    Ding, Lin; Beichner, Robert

    2009-01-01

    This paper introduces five commonly used approaches to analyzing multiple-choice test data. They are classical test theory, factor analysis, cluster analysis, item response theory, and model analysis. Brief descriptions of the goals and algorithms of these approaches are provided, together with examples illustrating their applications in physics…

  3. Reproducible statistical analysis with multiple languages

    DEFF Research Database (Denmark)

    Lenth, Russell; Højsgaard, Søren

    2011-01-01

    This paper describes the system for making reproducible statistical analyses. differs from other systems for reproducible analysis in several ways. The two main differences are: (1) Several statistics programs can be in used in the same document. (2) Documents can be prepared using OpenOffice or ......Office or \\LaTeX. The main part of this paper is an example showing how to use and together in an OpenOffice text document. The paper also contains some practical considerations on the use of literate programming in statistics....

  4. Analysis of Clinical Cohort Data Using Nested Case-control and Case-cohort Sampling Designs. A Powerful and Economical Tool.

    Science.gov (United States)

    Ohneberg, K; Wolkewitz, M; Beyersmann, J; Palomar-Martinez, M; Olaechea-Astigarraga, P; Alvarez-Lerma, F; Schumacher, M

    2015-01-01

    Sampling from a large cohort in order to derive a subsample that would be sufficient for statistical analysis is a frequently used method for handling large data sets in epidemiological studies with limited resources for exposure measurement. For clinical studies however, when interest is in the influence of a potential risk factor, cohort studies are often the first choice with all individuals entering the analysis. Our aim is to close the gap between epidemiological and clinical studies with respect to design and power considerations. Schoenfeld's formula for the number of events required for a Cox' proportional hazards model is fundamental. Our objective is to compare the power of analyzing the full cohort and the power of a nested case-control and a case-cohort design. We compare formulas for power for sampling designs and cohort studies. In our data example we simultaneously apply a nested case-control design with a varying number of controls matched to each case, a case cohort design with varying subcohort size, a random subsample and a full cohort analysis. For each design we calculate the standard error for estimated regression coefficients and the mean number of distinct persons, for whom covariate information is required. The formula for the power of a nested case-control design and the power of a case-cohort design is directly connected to the power of a cohort study using the well known Schoenfeld formula. The loss in precision of parameter estimates is relatively small compared to the saving in resources. Nested case-control and case-cohort studies, but not random subsamples yield an attractive alternative for analyzing clinical studies in the situation of a low event rate. Power calculations can be conducted straightforwardly to quantify the loss of power compared to the savings in the num-ber of patients using a sampling design instead of analyzing the full cohort.

  5. Alagille syndrome in a Vietnamese cohort: mutation analysis and assessment of facial features.

    Science.gov (United States)

    Lin, Henry C; Le Hoang, Phuc; Hutchinson, Anne; Chao, Grace; Gerfen, Jennifer; Loomes, Kathleen M; Krantz, Ian; Kamath, Binita M; Spinner, Nancy B

    2012-05-01

    Alagille syndrome (ALGS, OMIM #118450) is an autosomal dominant disorder that affects multiple organ systems including the liver, heart, eyes, vertebrae, and face. ALGS is caused by mutations in one of two genes in the Notch Signaling Pathway, Jagged1 (JAG1) or NOTCH2. In this study, analysis of 21 Vietnamese ALGS individuals led to the identification of 19 different mutations (18 JAG1 and 1 NOTCH2), 17 of which are novel, including the third reported NOTCH2 mutation in Alagille Syndrome. The spectrum of JAG1 mutations in the Vietnamese patients is similar to that previously reported, including nine frameshift, three missense, two splice site, one nonsense, two whole gene, and one partial gene deletion. The missense mutations are all likely to be disease causing, as two are loss of cysteines (C22R and C78G) and the third creates a cryptic splice site in exon 9 (G386R). No correlation between genotype and phenotype was observed. Assessment of clinical phenotype revealed that skeletal manifestations occur with a higher frequency than in previously reported Alagille cohorts. Facial features were difficult to assess and a Vietnamese pediatric gastroenterologist was only able to identify the facial phenotype in 61% of the cohort. To assess the agreement among North American dysmorphologists at detecting the presence of ALGS facial features in the Vietnamese patients, 37 clinical dysmorphologists evaluated a photographic panel of 20 Vietnamese children with and without ALGS. The dysmorphologists were unable to identify the individuals with ALGS in the majority of cases, suggesting that evaluation of facial features should not be used in the diagnosis of ALGS in this population. This is the first report of mutations and phenotypic spectrum of ALGS in a Vietnamese population. Copyright © 2012 Wiley Periodicals, Inc.

  6. Non-accidental injury: a retrospective analysis of a large cohort

    International Nuclear Information System (INIS)

    Carty, Helen; Pierce, Agnes

    2002-01-01

    The radiology literature describing the injuries of child abuse is very extensive. Articles on the distribution of injuries and the way in which a diagnosis was reached are less frequent. This article represents the detailed analysis of a cohort of patients, suspected of being victims of abuse, referred to the authors. It necessarily reflects personal experience and is not a population study. The distribution of the injuries in a cohort of 467 patients is reviewed. (orig.)

  7. Non-accidental injury: a retrospective analysis of a large cohort

    Energy Technology Data Exchange (ETDEWEB)

    Carty, Helen; Pierce, Agnes [RLC NHS Trust-Alder Hey, Liverpool L12 2 AP (United Kingdom)

    2002-12-01

    The radiology literature describing the injuries of child abuse is very extensive. Articles on the distribution of injuries and the way in which a diagnosis was reached are less frequent. This article represents the detailed analysis of a cohort of patients, suspected of being victims of abuse, referred to the authors. It necessarily reflects personal experience and is not a population study. The distribution of the injuries in a cohort of 467 patients is reviewed. (orig.)

  8. Neuropsychological, balance, and mobility risk factors for falls in people with multiple sclerosis: a prospective cohort study.

    Science.gov (United States)

    Hoang, Phu D; Cameron, Michelle H; Gandevia, Simon C; Lord, Stephen R

    2014-03-01

    To determine whether impaired performance in a range of vision, proprioception, neuropsychological, balance, and mobility tests and pain and fatigue are associated with falls in people with multiple sclerosis (PwMS). Prospective cohort study with 6-month follow-up. A multiple sclerosis (MS) physiotherapy clinic. Community-dwelling people (N=210; age range, 21-74y) with MS (Disease Steps 0-5). Not applicable. Incidence of falls during 6 months' follow-up. In the 6-month follow-up period, 83 participants (39.7%) experienced no falls, 57 (27.3%) fell once or twice, and 69 (33.0%) fell 3 or more times. Frequent falling (≥3) was associated with increased postural sway (eyes open and closed), poor leaning balance (as assessed with the coordinated stability task), slow choice stepping reaction time, reduced walking speed, reduced executive functioning (as assessed with the difference between Trail Making Test Part B and Trail Making Test Part A), reduced fine motor control (performance on the 9-Hole Peg Test [9-HPT]), and reported leg pain. Increased sway with the eyes closed, poor coordinated stability, and reduced performance in the 9-HPT were identified as variables that significantly and independently discriminated between frequent fallers and nonfrequent fallers (model χ(2)3=30.1, Pbalance, coordination, and cognitive determinants of falls in PwMS. These should assist the development of effective strategies for prevention of falls in this high-risk group. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  9. Role of BMI and age in predicting pathologic vertebral fractures in newly diagnosed multiple myeloma patients: A retrospective cohort study.

    Science.gov (United States)

    Chen, Yi-Lun; Liu, Yao-Chung; Wu, Chia-Hung; Yeh, Chiu-Mei; Chiu, Hsun-I; Lee, Gin-Yi; Lee, Yu-Ting; Hsu, Pei; Lin, Ting-Wei; Gau, Jyh-Pyng; Hsiao, Liang-Tsai; Chiou, Tzeon-Jye; Liu, Jin-Hwang; Liu, Chia-Jen

    2018-04-01

    Vertebral fractures affect approximately 30% of myeloma patients and lead to a poor impact on survival and life quality. In general, age and body mass index (BMI) are reported to have an important role in vertebral fractures. However, the triangle relationship among age, BMI, and vertebral fractures is still unclear in newly diagnosed multiple myeloma (NDMM) patients. This study recruited consecutive 394 patients with NDMM at Taipei Veterans General Hospital between January 1, 2005 and December 31, 2015. Risk factors for vertebral fractures in NDMM patients were collected and analyzed. The survival curves were demonstrated using Kaplan-Meier estimate. In total, 301 (76.4%) NDMM patients were enrolled in the cohort. In the median follow-up period of 18.0 months, the median survival duration in those with vertebral fractures ≥ 2 was shorter than those with vertebral fracture BMI BMI ≥ 24.0 kg/m 2 (adjusted RR, 2.79; 95% CI, 1.44-5.43). In multivariable logistic regression, BMI BMI ≥ 24.0 kg/m 2 (adjusted OR, 6.05; 95% CI, 2.43-15.08). Among age stratifications, patients with both old age and low BMI were at a greater risk suffering from increased vertebral fractures, especially in patients > 75 years and BMI BMI. Elder patients with low BMI should consider to routinely receive spinal radiographic examinations and regular follow-up. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Multiple scattering problems in heavy ion elastic recoil detection analysis

    International Nuclear Information System (INIS)

    Johnston, P.N.; El Bouanani, M.; Stannard, W.B.; Bubb, I.F.; Cohen, D.D.; Dytlewski, N.; Siegele, R.

    1998-01-01

    A number of groups use Heavy Ion Elastic Recoil Detection Analysis (HIERDA) to study materials science problems. Nevertheless, there is no standard methodology for the analysis of HIERDA spectra. To overcome this deficiency we have been establishing codes for 2-dimensional data analysis. A major problem involves the effects of multiple and plural scattering which are very significant, even for quite thin (∼100 nm) layers of the very heavy elements. To examine the effects of multiple scattering we have made comparisons between the small-angle model of Sigmund et al. and TRIM calculations. (authors)

  11. Chocolate consumption and risk of atrial fibrillation: Two cohort studies and a meta-analysis.

    Science.gov (United States)

    Larsson, Susanna C; Drca, Nikola; Jensen-Urstad, Mats; Wolk, Alicja

    2018-01-01

    Chocolate consumption has been inconsistently associated with risk of atrial fibrillation (AF). We investigated the association between chocolate consumption and risk of AF in Swedish adults from two cohort studies and conducted a meta-analysis to summarize available evidence from cohort studies on this topic. Our study population comprised 40,009 men from the Cohort of Swedish Men and 32,486 women from the Swedish Mammography Cohort. Incident AF cases were ascertained through linkage with the Swedish National Patient Register. Published cohort studies of chocolate consumption in relation to risk of AF were identified by a PubMed search through September 14, 2017. During a mean follow-up of 14.6 years, AF was diagnosed in 9978 Swedish men and women. Compared with non-consumers, the multivariable hazard ratio of AF for those in the highest category of chocolate consumption (≥3-4 servings/week) was 0.96 (95% CI 0.88-1.04). In a random-effects meta-analysis of 5 cohort studies, including 180,454 participants and 16,356 AF cases, the hazard ratios of AF were 0.97 (95% CI 0.94-1.01) per 2 servings/week increase in chocolate consumption and 0.96 (95% CI 0.90-1.03) for the highest versus lowest category of chocolate consumption. Available data provide no evidence of an association of chocolate consumption with risk of AF. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Approaches to data analysis of multiple-choice questions

    Directory of Open Access Journals (Sweden)

    Lin Ding

    2009-09-01

    Full Text Available This paper introduces five commonly used approaches to analyzing multiple-choice test data. They are classical test theory, factor analysis, cluster analysis, item response theory, and model analysis. Brief descriptions of the goals and algorithms of these approaches are provided, together with examples illustrating their applications in physics education research. We minimize mathematics, instead placing emphasis on data interpretation using these approaches.

  13. Analysis of multiple scattering effects in optical Doppler tomography

    DEFF Research Database (Denmark)

    Yura, H.T.; Thrane, L.; Andersen, Peter E.

    2005-01-01

    Optical Doppler tomography (ODT) combines Doppler velocimetry and optical coherence tomography (OCT) to obtain high-resolution cross-sectional imaging of particle flow velocity in scattering media such as the human retina and skin. Here, we present the results of a theoretical analysis of ODT where...... multiple scattering effects are included. The purpose of this analysis is to determine how multiple scattering affects the estimation of the depth-resolved localized flow velocity. Depth-resolved velocity estimates are obtained directly from the corresponding mean or standard deviation of the observed...

  14. Integrative Analysis of Prognosis Data on Multiple Cancer Subtypes

    Science.gov (United States)

    Liu, Jin; Huang, Jian; Zhang, Yawei; Lan, Qing; Rothman, Nathaniel; Zheng, Tongzhang; Ma, Shuangge

    2014-01-01

    Summary In cancer research, profiling studies have been extensively conducted, searching for genes/SNPs associated with prognosis. Cancer is diverse. Examining the similarity and difference in the genetic basis of multiple subtypes of the same cancer can lead to a better understanding of their connections and distinctions. Classic meta-analysis methods analyze each subtype separately and then compare analysis results across subtypes. Integrative analysis methods, in contrast, analyze the raw data on multiple subtypes simultaneously and can outperform meta-analysis methods. In this study, prognosis data on multiple subtypes of the same cancer are analyzed. An AFT (accelerated failure time) model is adopted to describe survival. The genetic basis of multiple subtypes is described using the heterogeneity model, which allows a gene/SNP to be associated with prognosis of some subtypes but not others. A compound penalization method is developed to identify genes that contain important SNPs associated with prognosis. The proposed method has an intuitive formulation and is realized using an iterative algorithm. Asymptotic properties are rigorously established. Simulation shows that the proposed method has satisfactory performance and outperforms a penalization-based meta-analysis method and a regularized thresholding method. An NHL (non-Hodgkin lymphoma) prognosis study with SNP measurements is analyzed. Genes associated with the three major subtypes, namely DLBCL, FL, and CLL/SLL, are identified. The proposed method identifies genes that are different from alternatives and have important implications and satisfactory prediction performance. PMID:24766212

  15. Mitochondrial disease in autism spectrum disorder patients: a cohort analysis.

    Science.gov (United States)

    Weissman, Jacqueline R; Kelley, Richard I; Bauman, Margaret L; Cohen, Bruce H; Murray, Katherine F; Mitchell, Rebecca L; Kern, Rebecca L; Natowicz, Marvin R

    2008-01-01

    Previous reports indicate an association between autism spectrum disorders (ASD) and disorders of mitochondrial oxidative phosphorylation. One study suggested that children with both diagnoses are clinically indistinguishable from children with idiopathic autism. There are, however, no detailed analyses of the clinical and laboratory findings in a large cohort of these children. Therefore, we undertook a comprehensive review of patients with ASD and a mitochondrial disorder. We reviewed medical records of 25 patients with a primary diagnosis of ASD by DSM-IV-TR criteria, later determined to have enzyme- or mutation-defined mitochondrial electron transport chain (ETC) dysfunction. Twenty-four of 25 patients had one or more major clinical abnormalities uncommon in idiopathic autism. Twenty-one patients had histories of significant non-neurological medical problems. Nineteen patients exhibited constitutional symptoms, especially excessive fatigability. Fifteen patients had abnormal neurological findings. Unusual developmental phenotypes included marked delay in early gross motor milestones (32%) and unusual patterns of regression (40%). Levels of blood lactate, plasma alanine, and serum ALT and/or AST were increased at least once in 76%, 36%, and 52% of patients, respectively. The most common ETC disorders were deficiencies of complex I (64%) and complex III (20%). Two patients had rare mtDNA mutations of likely pathogenicity. Although all patients' initial diagnosis was idiopathic autism, careful clinical and biochemical assessment identified clinical findings that differentiated them from children with idiopathic autism. These and prior data suggest a disturbance of mitochondrial energy production as an underlying pathophysiological mechanism in a subset of individuals with autism.

  16. Mitochondrial disease in autism spectrum disorder patients: a cohort analysis.

    Directory of Open Access Journals (Sweden)

    Jacqueline R Weissman

    Full Text Available Previous reports indicate an association between autism spectrum disorders (ASD and disorders of mitochondrial oxidative phosphorylation. One study suggested that children with both diagnoses are clinically indistinguishable from children with idiopathic autism. There are, however, no detailed analyses of the clinical and laboratory findings in a large cohort of these children. Therefore, we undertook a comprehensive review of patients with ASD and a mitochondrial disorder.We reviewed medical records of 25 patients with a primary diagnosis of ASD by DSM-IV-TR criteria, later determined to have enzyme- or mutation-defined mitochondrial electron transport chain (ETC dysfunction. Twenty-four of 25 patients had one or more major clinical abnormalities uncommon in idiopathic autism. Twenty-one patients had histories of significant non-neurological medical problems. Nineteen patients exhibited constitutional symptoms, especially excessive fatigability. Fifteen patients had abnormal neurological findings. Unusual developmental phenotypes included marked delay in early gross motor milestones (32% and unusual patterns of regression (40%. Levels of blood lactate, plasma alanine, and serum ALT and/or AST were increased at least once in 76%, 36%, and 52% of patients, respectively. The most common ETC disorders were deficiencies of complex I (64% and complex III (20%. Two patients had rare mtDNA mutations of likely pathogenicity.Although all patients' initial diagnosis was idiopathic autism, careful clinical and biochemical assessment identified clinical findings that differentiated them from children with idiopathic autism. These and prior data suggest a disturbance of mitochondrial energy production as an underlying pathophysiological mechanism in a subset of individuals with autism.

  17. Multiple lifestyle behaviours and mortality, findings from a large population-based Norwegian cohort study - The HUNT Study

    Directory of Open Access Journals (Sweden)

    Steinar Krokstad

    2017-01-01

    Full Text Available Abstract Background Lifestyle risk behaviours are responsible for a large proportion of disease burden and premature mortality worldwide. Risk behaviours tend to cluster in populations. We developed a new lifestyle risk index by including emerging risk factors (sleep, sitting time, and social participation and examine unique risk combinations and their associations with all-cause and cardio-metabolic mortality. Methods Data are from a large population-based cohort study in a Norway, the Nord-Trøndelag Health Study (HUNT, with an average follow-up time of 14.1 years. Baseline data from 1995–97 were linked to the Norwegian Causes of Death Registry. The analytic sample comprised 36 911 adults aged 20–69 years. Cox regression models were first fitted for seven risk factors (poor diet, excessive alcohol consumption, current smoking, physical inactivity, excessive sitting, too much/too little sleep, and poor social participation separately and then adjusted for socio-demographic covariates. Based on these results, a lifestyle risk index was developed. Finally, we explored common combinations of the risk factors in relation to all-cause and cardio-metabolic mortality outcomes. Results All single risk factors, except for diet, were significantly associated with both mortality outcomes, and were therefore selected to form a lifestyle risk index. Risk of mortality increased as the index score increased. The hazard ratio for all-cause mortality increased from 1.37 (1.15-1.62 to 6.15 (3.56-10.63 as the number of index risk factors increased from one to six respectively. Among the most common risk factor combinations the association with mortality was particularly strong when smoking and/or social participation were included. Conclusions This study adds to previous research on multiple risk behaviours by incorporating emerging risk factors. Findings regarding social participation and prolonged sitting suggest new components of healthy lifestyles and

  18. Evaluation of dairy effluent management options using multiple criteria analysis.

    Science.gov (United States)

    Hajkowicz, Stefan A; Wheeler, Sarah A

    2008-04-01

    This article describes how options for managing dairy effluent on the Lower Murray River in South Australia were evaluated using multiple criteria analysis (MCA). Multiple criteria analysis is a framework for combining multiple environmental, social, and economic objectives in policy decisions. At the time of the study, dairy irrigation in the region was based on flood irrigation which involved returning effluent to the river. The returned water contained nutrients, salts, and microbial contaminants leading to environmental, human health, and tourism impacts. In this study MCA was used to evaluate 11 options against 6 criteria for managing dairy effluent problems. Of the 11 options, the MCA model selected partial rehabilitation of dairy paddocks with the conversion of remaining land to other agriculture. Soon after, the South Australian Government adopted this course of action and is now providing incentives for dairy farmers in the region to upgrade irrigation infrastructure and/or enter alternative industries.

  19. Trends in Dementia Incidence in a Birth Cohort Analysis of the Einstein Aging Study.

    Science.gov (United States)

    Derby, Carol A; Katz, Mindy J; Lipton, Richard B; Hall, Charles B

    2017-11-01

    Trends in dementia incidence rates have important implications for planning and prevention. To better understand incidence trends over time requires separation of age and cohort effects, and few prior studies have used this approach. To examine trends in dementia incidence and concomitant trends in cardiovascular comorbidities among individuals aged 70 years or older who were enrolled in the Einstein Aging Study between 1993 and 2015. In this birth cohort analysis of all-cause dementia incidence in persons enrolled in the Einstein Aging Study from October 20, 1993, through November 17, 2015, a systematically recruited, population-based sample of 1348 participants from Bronx County, New York, who were 70 years or older without dementia at enrollment and at least one annual follow-up was studied. Poisson regression was used to model dementia incidence as a function of age, sex, educational level, race, and birth cohort, with profile likelihood used to identify the timing of significant increases or decreases in incidence. Birth year and age. Incident dementia defined by consensus case conference based on annual, standardized neuropsychological and neurologic examination findings, using criteria from the DSM-IV. Among 1348 individuals (mean [SD] baseline age, 78.5 [5.4] years; 830 [61.6%] female; 915 [67.9%] non-Hispanic white), 150 incident dementia cases developed during 5932 person-years (mean [SD] follow-up, 4.4 [3.4] years). Dementia incidence decreased in successive birth cohorts. Incidence per 100 person-years was 5.09 in birth cohorts before 1920, 3.11 in the 1920 through 1924 birth cohorts, 1.73 in the 1925 through 1929 birth cohorts, and 0.23 in cohorts born after 1929. Change point analyses identified a significant decrease in dementia incidence among those born after July 1929 (95% CI, June 1929 to January 1930). The relative rate for birth cohorts before July 1929 vs after was 0.13 (95% CI, 0.04-0.41). Prevalence of stroke and myocardial infarction

  20. A Historical Cohort Study on the Efficacy of Glucocorticoids and Riboflavin Among Patients with Late-onset Multiple Acyl-CoA Dehydrogenase Deficiency.

    Science.gov (United States)

    Liu, Xin-Yi; Wang, Zhi-Qiang; Wang, Dan-Ni; Lin, Min-Ting; Wang, Ning

    2016-01-20

    Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is the most common type of lipid storage myopathies in China. Most patients with late-onset MADD are well responsive to riboflavin. Up to now, these patients are often treated with glucocorticoids as the first-line drug because they are misdiagnosed as polymyositis without muscle biopsy or gene analysis. Although glucocorticoids seem to improve the fatty acid metabolism of late-onset MADD, the objective evaluation of their rationalization on this disorder and comparison with riboflavin treatment are unknown. We performed a historical cohort study on the efficacy of the two drugs among 45 patients with late-onset MADD, who were divided into glucocorticoids group and riboflavin group. Detailed clinical information of baseline and 1-month follow-up were collected. After 1-month treatment, a dramatic improvement of muscle strength was found in riboflavin group (P riboflavin group (P riboflavin group still presented high-level muscle enzymes and weak muscle strength after 1-month riboflavin treatment, meaning that 1-month treatment duration maybe insufficient and patients should keep on riboflavin supplement for a longer time. Our results provide credible evidences that the overall efficacy of riboflavin is superior to glucocorticoids, and a longer duration of riboflavin treatment is necessary for patients with late-onset MADD.

  1. General Nature of Multicollinearity in Multiple Regression Analysis.

    Science.gov (United States)

    Liu, Richard

    1981-01-01

    Discusses multiple regression, a very popular statistical technique in the field of education. One of the basic assumptions in regression analysis requires that independent variables in the equation should not be highly correlated. The problem of multicollinearity and some of the solutions to it are discussed. (Author)

  2. MULGRES: a computer program for stepwise multiple regression analysis

    Science.gov (United States)

    A. Jeff Martin

    1971-01-01

    MULGRES is a computer program source deck that is designed for multiple regression analysis employing the technique of stepwise deletion in the search for most significant variables. The features of the program, along with inputs and outputs, are briefly described, with a note on machine compatibility.

  3. Social relationships and cognitive decline: a systematic review and meta-analysis of longitudinal cohort studies.

    Science.gov (United States)

    Kuiper, Jisca S; Zuidersma, Marij; Zuidema, Sytse U; Burgerhof, Johannes Gm; Stolk, Ronald P; Oude Voshaar, Richard C; Smidt, Nynke

    2016-08-01

    Although poor social relationships are assumed to contribute to cognitive decline, meta-analytic approaches have not been applied. Individual study results are mixed and difficult to interpret due to heterogeneity in measures of social relationships. We conducted a systematic review and meta-analysis to investigate the relation between poor social relationships and cognitive decline. MEDLINE, Embase and PsycINFO were searched for longitudinal cohort studies examining various aspects of social relationships and cognitive decline in the general population. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using random effects meta-analysis. Sources of heterogeneity were explored and likelihood of publication bias was assessed. We stratified analyses according to three aspects of social relationships: structural, functional and a combination of these. We identified 43 articles. Poor social relationships predicted cognitive decline; for structural (19 studies): pooled OR: 1.08 (95% CI: 1.05-1.11); functional (8 studies): pooled OR: 1.15 (95% CI: 1.00-1.32); and combined measures (7 studies): pooled OR: 1.12 (95% CI: 1.01-1.24). Meta-regression and subgroup analyses showed that the heterogeneity could be explained by the type of social relationship measurement and methodological quality of included studies. Despite heterogeneity in study design and measures, our meta-analyses show that multiple aspects of social relationships are associated with cognitive decline. As evidence for publication bias was found, the association might be overestimated and should therefore be interpreted with caution. Future studies are needed to better define the mechanisms underlying these associations. Potential causality of this prognostic association should be examined in future randomized controlled studies. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

  4. The epidemiology of adolescents living with perinatally acquired HIV: A cross-region global cohort analysis.

    Directory of Open Access Journals (Sweden)

    Amy L Slogrove

    2018-03-01

    Full Text Available Globally, the population of adolescents living with perinatally acquired HIV (APHs continues to expand. In this study, we pooled data from observational pediatric HIV cohorts and cohort networks, allowing comparisons of adolescents with perinatally acquired HIV in "real-life" settings across multiple regions. We describe the geographic and temporal characteristics and mortality outcomes of APHs across multiple regions, including South America and the Caribbean, North America, Europe, sub-Saharan Africa, and South and Southeast Asia.Through the Collaborative Initiative for Paediatric HIV Education and Research (CIPHER, individual retrospective longitudinal data from 12 cohort networks were pooled. All children infected with HIV who entered care before age 10 years, were not known to have horizontally acquired HIV, and were followed up beyond age 10 years were included in this analysis conducted from May 2016 to January 2017. Our primary analysis describes patient and treatment characteristics of APHs at key time points, including first HIV-associated clinic visit, antiretroviral therapy (ART start, age 10 years, and last visit, and compares these characteristics by geographic region, country income group (CIG, and birth period. Our secondary analysis describes mortality, transfer out, and lost to follow-up (LTFU as outcomes at age 15 years, using competing risk analysis. Among the 38,187 APHs included, 51% were female, 79% were from sub-Saharan Africa and 65% lived in low-income countries. APHs from 51 countries were included (Europe: 14 countries and 3,054 APHs; North America: 1 country and 1,032 APHs; South America and the Caribbean: 4 countries and 903 APHs; South and Southeast Asia: 7 countries and 2,902 APHs; sub-Saharan Africa, 25 countries and 30,296 APHs. Observation started as early as 1982 in Europe and 1996 in sub-Saharan Africa, and continued until at least 2014 in all regions. The median (interquartile range [IQR] duration of

  5. The epidemiology of adolescents living with perinatally acquired HIV: A cross-region global cohort analysis.

    Science.gov (United States)

    Slogrove, Amy L; Schomaker, Michael; Davies, Mary-Ann; Williams, Paige; Balkan, Suna; Ben-Farhat, Jihane; Calles, Nancy; Chokephaibulkit, Kulkanya; Duff, Charlotte; Eboua, Tanoh François; Kekitiinwa-Rukyalekere, Adeodata; Maxwell, Nicola; Pinto, Jorge; Seage, George; Teasdale, Chloe A; Wanless, Sebastian; Warszawski, Josiane; Wools-Kaloustian, Kara; Yotebieng, Marcel; Timmerman, Venessa; Collins, Intira J; Goodall, Ruth; Smith, Colette; Patel, Kunjal; Paul, Mary; Gibb, Diana; Vreeman, Rachel; Abrams, Elaine J; Hazra, Rohan; Van Dyke, Russell; Bekker, Linda-Gail; Mofenson, Lynne; Vicari, Marissa; Essajee, Shaffiq; Penazzato, Martina; Anabwani, Gabriel; Q Mohapi, Edith; N Kazembe, Peter; Hlatshwayo, Makhosazana; Lumumba, Mwita; Goetghebuer, Tessa; Thorne, Claire; Galli, Luisa; van Rossum, Annemarie; Giaquinto, Carlo; Marczynska, Magdalena; Marques, Laura; Prata, Filipa; Ene, Luminita; Okhonskaia, Liubov; Rojo, Pablo; Fortuny, Claudia; Naver, Lars; Rudin, Christoph; Le Coeur, Sophie; Volokha, Alla; Rouzier, Vanessa; Succi, Regina; Sohn, Annette; Kariminia, Azar; Edmonds, Andrew; Lelo, Patricia; Ayaya, Samuel; Ongwen, Patricia; Jefferys, Laura F; Phiri, Sam; Mubiana-Mbewe, Mwangelwa; Sawry, Shobna; Renner, Lorna; Sylla, Mariam; Abzug, Mark J; Levin, Myron; Oleske, James; Chernoff, Miriam; Traite, Shirley; Purswani, Murli; Chadwick, Ellen G; Judd, Ali; Leroy, Valériane

    2018-03-01

    Globally, the population of adolescents living with perinatally acquired HIV (APHs) continues to expand. In this study, we pooled data from observational pediatric HIV cohorts and cohort networks, allowing comparisons of adolescents with perinatally acquired HIV in "real-life" settings across multiple regions. We describe the geographic and temporal characteristics and mortality outcomes of APHs across multiple regions, including South America and the Caribbean, North America, Europe, sub-Saharan Africa, and South and Southeast Asia. Through the Collaborative Initiative for Paediatric HIV Education and Research (CIPHER), individual retrospective longitudinal data from 12 cohort networks were pooled. All children infected with HIV who entered care before age 10 years, were not known to have horizontally acquired HIV, and were followed up beyond age 10 years were included in this analysis conducted from May 2016 to January 2017. Our primary analysis describes patient and treatment characteristics of APHs at key time points, including first HIV-associated clinic visit, antiretroviral therapy (ART) start, age 10 years, and last visit, and compares these characteristics by geographic region, country income group (CIG), and birth period. Our secondary analysis describes mortality, transfer out, and lost to follow-up (LTFU) as outcomes at age 15 years, using competing risk analysis. Among the 38,187 APHs included, 51% were female, 79% were from sub-Saharan Africa and 65% lived in low-income countries. APHs from 51 countries were included (Europe: 14 countries and 3,054 APHs; North America: 1 country and 1,032 APHs; South America and the Caribbean: 4 countries and 903 APHs; South and Southeast Asia: 7 countries and 2,902 APHs; sub-Saharan Africa, 25 countries and 30,296 APHs). Observation started as early as 1982 in Europe and 1996 in sub-Saharan Africa, and continued until at least 2014 in all regions. The median (interquartile range [IQR]) duration of adolescent follow

  6. Multiple Autoantibodies Display Association with Lymphopenia, Proteinuria, and Cellular Casts in a Large, Ethnically Diverse SLE Patient Cohort

    Directory of Open Access Journals (Sweden)

    Rufei Lu

    2012-01-01

    Full Text Available Purpose. This study evaluates high-throughput autoantibody screening and determines associated systemic lupus erythematosus (SLE clinical features in a large lupus cohort. Methods. Clinical and demographic information, along with serum samples, were obtained from each SLE study participant after appropriate informed consent. Serum samples were screened for 10 distinct SLE autoantibody specificities and examined for association with SLE ACR criteria and subcriteria using conditional logistic regression analysis. Results. In European-American SLE patients, autoantibodies against 52 kD Ro and RNP 68 are independently enriched in patients with lymphopenia, anti-La, and anti-ribosomal P are increased in patients with malar rash, and anti-dsDNA and anti-Sm are enriched in patients with proteinuria. In African-American SLE patients, cellular casts associate with autoantibodies against dsDNA, Sm, and Sm/nRNP. Conclusion. Using a high-throughput, bead-based method of autoantibody detection, anti-dsDNA is significantly enriched in patienets with SLE ACR renal criteria as has been previously described. However, lymphopenia is associated with several distinct autoantibody specificities. These findings offer meaningful information to allow clinicians and clinical investigators to understand which autoantibodies correlate with select SLE clinical manifestations across common racial groups using this novel methodology which is expanding in clinical use.

  7. Exploration of preterm birth rates associated with different models of antenatal midwifery care in Scotland: Unmatched retrospective cohort analysis.

    Science.gov (United States)

    Symon, Andrew; Winter, Clare; Cochrane, Lynda

    2015-06-01

    resonates with other research, including the recent Cochrane review of midwife-led continuity models. Because of the multiplicity of risk factors for preterm birth we need to explore the salient features of the FMU model which may be contributing to this apparent protective effect. Because a randomised controlled trial would necessarily restrict choice to pregnant women, we feel that this option is problematic in exploring this further. We therefore plan to conduct a prospective matched cohort analysis together with a survey of unit practices and experiences. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Cohort analysis of a single nucleotide polymorphism on DNA chips.

    Science.gov (United States)

    Schwonbeck, Susanne; Krause-Griep, Andrea; Gajovic-Eichelmann, Nenad; Ehrentreich-Förster, Eva; Meinl, Walter; Glatt, Hansrüdi; Bier, Frank F

    2004-11-15

    A method has been developed to determine SNPs on DNA chips by applying a flow-through bioscanner. As a practical application we demonstrated the fast and simple SNP analysis of 24 genotypes in an array of 96 spots with a single hybridisation and dissociation experiment. The main advantage of this methodical concept is the parallel and fast analysis without any need of enzymatic digestion. Additionally, the DNA chip format used is appropriate for parallel analysis up to 400 spots. The polymorphism in the gene of the human phenol sulfotransferase SULT1A1 was studied as a model SNP. Biotinylated PCR products containing the SNP (The SNP summary web site: ) (mutant) and those containing no mutation (wild-type) were brought onto the chips coated with NeutrAvidin using non-contact spotting. This was followed by an analysis which was carried out in a flow-through biochip scanner while constantly rinsing with buffer. After removing the non-biotinylated strand a fluorescent probe was hybridised, which is complementary to the wild-type sequence. If this probe binds to a mutant sequence, then one single base is not fully matching. Thereby, the mismatched hybrid (mutant) is less stable than the full-matched hybrid (wild-type). The final step after hybridisation on the chip involves rinsing with a buffer to start dissociation of the fluorescent probe from the immobilised DNA strand. The online measurement of the fluorescence intensity by the biochip scanner provides the possibility to follow the kinetics of the hybridisation and dissociation processes. According to the different stability of the full-match and the mismatch, either visual discrimination or kinetic analysis is possible to distinguish SNP-containing sequence from the wild-type sequence.

  9. Steady State Analysis of Stochastic Systems with Multiple Time Delays

    Science.gov (United States)

    Xu, W.; Sun, C. Y.; Zhang, H. Q.

    In this paper, attention is focused on the steady state analysis of a class of nonlinear dynamic systems with multi-delayed feedbacks driven by multiplicative correlated Gaussian white noises. The Fokker-Planck equations for delayed variables are at first derived by Novikov's theorem. Then, under small delay assumption, the approximate stationary solutions are obtained by the probability density approach. As a special case, the effects of multidelay feedbacks and the correlated additive and multiplicative Gaussian white noises on the response of a bistable system are considered. It is shown that the obtained analytical results are in good agreement with experimental results in Monte Carlo simulations.

  10. Decreasing Sports Activity with Increasing Age? Findings from a 20-Year Longitudinal and Cohort Sequence Analysis

    Science.gov (United States)

    Breuer, Christoph; Wicker, Pamela

    2009-01-01

    According to cross-sectional studies in sport science literature, decreasing sports activity with increasing age is generally assumed. In this paper, the validity of this assumption is checked by applying more effective methods of analysis, such as longitudinal and cohort sequence analyses. With the help of 20 years' worth of data records from the…

  11. Efficiency aspects of design and analysis of prospective cohort studies on diet, nutrition and cancer

    NARCIS (Netherlands)

    Kaaks, R.J.

    1994-01-01

    This thesis presents and analyzes methodological approaches to improve the design and analysis of prospective cohort studies on the relations between diet, nutritional status and cancer. The first chapters discuss methods to optimize the measurement of the individuals' habitual dietary

  12. Human Endogenous Retrovirus HERV-Fc1 Association with Multiple Sclerosis Susceptibility: A Meta-Analysis

    Science.gov (United States)

    García-Montojo, Marta; Alcina, Antonio; Fedetz, María; Alloza, Iraide; Astobiza, Ianire; Leyva, Laura; Fernández, Oscar; Izquierdo, Guillermo; Antigüedad, Alfredo; Arroyo, Rafael; Álvarez-Lafuente, Roberto; Vandenbroeck, Koen; Matesanz, Fuencisla; Urcelay, Elena

    2014-01-01

    Background Human endogenous retroviruses (HERVs) are repetitive sequences derived from ancestral germ-line infections by exogenous retroviruses and different HERV families have been integrated in the genome. HERV-Fc1 in chromosome X has been previously associated with multiple sclerosis (MS) in Northern European populations. Additionally, HERV-Fc1 RNA levels of expression have been found increased in plasma of MS patients with active disease. Considering the North-South latitude gradient in MS prevalence, we aimed to evaluate the role of HERV-Fc1on MS risk in three independent Spanish cohorts. Methods A single nucleotide polymorphism near HERV-Fc1, rs391745, was genotyped by Taqman chemistry in a total of 2473 MS patients and 3031 ethnically matched controls, consecutively recruited from: Northern (569 patients and 980 controls), Central (883 patients and 692 controls) and Southern (1021 patients and 1359 controls) Spain. Our results were pooled in a meta-analysis with previously published data. Results Significant associations of the HERV-Fc1 polymorphism with MS were observed in two Spanish cohorts and the combined meta-analysis with previous data yielded a significant association [rs391745 C-allele carriers: pM-H = 0.0005; ORM-H (95% CI) = 1.27 (1.11–1.45)]. Concordantly to previous findings, when the analysis was restricted to relapsing remitting and secondary progressive MS samples, a slight enhancement in the strength of the association was observed [pM-H = 0.0003, ORM-H (95% CI) = 1.32 (1.14–1.53)]. Conclusion Association of the HERV-Fc1 polymorphism rs391745 with bout-onset MS susceptibility was confirmed in Southern European cohorts. PMID:24594754

  13. HARMONIC ANALYSIS OF SVPWM INVERTER USING MULTIPLE-PULSES METHOD

    Directory of Open Access Journals (Sweden)

    Mehmet YUMURTACI

    2009-01-01

    Full Text Available Space Vector Modulation (SVM technique is a popular and an important PWM technique for three phases voltage source inverter in the control of Induction Motor. In this study harmonic analysis of Space Vector PWM (SVPWM is investigated using multiple-pulses method. Multiple-Pulses method calculates the Fourier coefficients of individual positive and negative pulses of the output PWM waveform and adds them together using the principle of superposition to calculate the Fourier coefficients of the all PWM output signal. Harmonic magnitudes can be calculated directly by this method without linearization, using look-up tables or Bessel functions. In this study, the results obtained in the application of SVPWM for values of variable parameters are compared with the results obtained with the multiple-pulses method.

  14. Cohort profile for the Nurture Observational Study examining associations of multiple caregivers on infant growth in the Southeastern USA.

    Science.gov (United States)

    Benjamin Neelon, Sara E; Østbye, Truls; Bennett, Gary G; Kravitz, Richard M; Clancy, Shayna M; Stroo, Marissa; Iversen, Edwin; Hoyo, Cathrine

    2017-02-08

    Childcare has been associated with obesity in children in cross-sectional and longitudinal studies, although some observed no association. Few studies have focused on care during infancy, a period when children may be especially vulnerable. The Nurture Study is an observational birth cohort designed to assess longitudinal associations of childcare and the presence of multiple caregivers on infant adiposity and weight trajectories throughout the first year of life. We examine as potential mediators feeding, physical activity, sleep and stress. We completed recruitment in 2015. Of the 860 women who enrolled during pregnancy, 799 delivered a single live infant who met our inclusion criteria. Of those, 666 mothers (77.4%) agreed to participate in the study for themselves and their infants. Among the 666 women in the study, 472 (71%) identified as black, 127 (19%) as white, 7 (1%) as Asian or Asian American, 6 (1%) as Native American and 49 (7%) as other race or more than one race; 43 (7%) identified as Hispanic/Latina. Just under half (48%) had a high school diploma or less, 61% had household incomes <$20 000/year and 59% were married or living with a partner. The mean (SD) infant gestational age was 41.28 weeks (2.29) and birth weight for gestational age z-score was -0.31 (0.93). Just under half (49%) of infants were females, 69% received some human milk and 40% were exclusively breast fed at hospital discharge. Data collection began in 2013, is currently underway, and is scheduled to conclude in late 2016. Results will help assess the magnitude of associations between childcare in infancy and subsequent obesity. Findings will also inform intervention and policy efforts to improve childcare environments and help prevent obesity in settings where many infants spend time. Clinicaltrials.gov, NCT01788644. 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/.

  15. Missing data treatments matter: an analysis of multiple imputation for anterior cervical discectomy and fusion procedures.

    Science.gov (United States)

    Ondeck, Nathaniel T; Fu, Michael C; Skrip, Laura A; McLynn, Ryan P; Cui, Jonathan J; Basques, Bryce A; Albert, Todd J; Grauer, Jonathan N

    2018-04-09

    The presence of missing data is a limitation of large datasets, including the National Surgical Quality Improvement Program (NSQIP). In addressing this issue, most studies use complete case analysis, which excludes cases with missing data, thus potentially introducing selection bias. Multiple imputation, a statistically rigorous approach that approximates missing data and preserves sample size, may be an improvement over complete case analysis. The present study aims to evaluate the impact of using multiple imputation in comparison with complete case analysis for assessing the associations between preoperative laboratory values and adverse outcomes following anterior cervical discectomy and fusion (ACDF) procedures. This is a retrospective review of prospectively collected data. Patients undergoing one-level ACDF were identified in NSQIP 2012-2015. Perioperative adverse outcome variables assessed included the occurrence of any adverse event, severe adverse events, and hospital readmission. Missing preoperative albumin and hematocrit values were handled using complete case analysis and multiple imputation. These preoperative laboratory levels were then tested for associations with 30-day postoperative outcomes using logistic regression. A total of 11,999 patients were included. Of this cohort, 63.5% of patients had missing preoperative albumin and 9.9% had missing preoperative hematocrit. When using complete case analysis, only 4,311 patients were studied. The removed patients were significantly younger, healthier, of a common body mass index, and male. Logistic regression analysis failed to identify either preoperative hypoalbuminemia or preoperative anemia as significantly associated with adverse outcomes. When employing multiple imputation, all 11,999 patients were included. Preoperative hypoalbuminemia was significantly associated with the occurrence of any adverse event and severe adverse events. Preoperative anemia was significantly associated with the

  16. Modular risk analysis for assessing multiple waste sites

    International Nuclear Information System (INIS)

    Whelan, G.; Buck, J.W.; Nazarali, A.

    1994-06-01

    Human-health impacts, especially to the surrounding public, are extremely difficult to assess at installations that contain multiple waste sites and a variety of mixed-waste constituents (e.g., organic, inorganic, and radioactive). These assessments must address different constituents, multiple waste sites, multiple release patterns, different transport pathways (i.e., groundwater, surface water, air, and overland soil), different receptor types and locations, various times of interest, population distributions, land-use patterns, baseline assessments, a variety of exposure scenarios, etc. Although the process is complex, two of the most important difficulties to overcome are associated with (1) establishing an approach that allows for modifying the source term, transport, or exposure component as an individual module without having to re-evaluate the entire installation-wide assessment (i.e., all modules simultaneously), and (2) displaying and communicating the results in an understandable and useable maimer to interested parties. An integrated, physics-based, compartmentalized approach, which is coupled to a Geographical Information System (GIS), captures the regional health impacts associated with multiple waste sites (e.g., hundreds to thousands of waste sites) at locations within and surrounding the installation. Utilizing a modular/GIS-based approach overcomes difficulties in (1) analyzing a wide variety of scenarios for multiple waste sites, and (2) communicating results from a complex human-health-impact analysis by capturing the essence of the assessment in a relatively elegant manner, so the meaning of the results can be quickly conveyed to all who review them

  17. Analysis of (n, 2n) multiplication in lead

    International Nuclear Information System (INIS)

    Segev, M.

    1984-01-01

    Lead is being considered as a possible amplifier of neutrons for fusion blankets. A simple one-group model of neutron multiplications in Pb is presented. Given the 14 MeV neutron cross section on Pb, the model predicts the multiplication. Given measured multiplications, the model enables the determination of the (n, 2n) and transport cross sections. Required for the model are: P-the collision probability for source neutrons in the Pb body-and W- an average collision probability for non-virgin, non-degraded neutrons. In simple geometries, such as a source in the center of a spherical shell, P and an approximate W can be expressed analytically in terms of shell dimensions and the Pb transport cross section. The model was applied to Takahashi's measured multiplications in Pb shells in order to understand the apparent very high multiplicative power of Pb. The results of the analysis are not consistent with basic energy-balance and cross section magnitude constraints in neutron interaction theory. (author)

  18. Multiplicity Analysis during Photon Interrogation of Fissionable Material

    International Nuclear Information System (INIS)

    Clarke, Shaun D.; Pozzi, Sara A.; Padovani, Enrico; Downar, Thomas J.

    2007-01-01

    Simulation of multiplicity distributions with the Monte Carlo method is difficult because each history is treated individually. In order to accurately model the multiplicity distribution, the intensity and time width of the interrogation pulse must be incorporated into the calculation. This behavior dictates how many photons arrive at the target essentially simultaneously. In order to model the pulse width correctly, a Monte Carlo code system consisting of modified versions of the codes MCNPX and MCNP-PoliMi has been developed in conjunction with a post-processing algorithm to operate on the MCNP-PoliMi output file. The purpose of this subroutine is to assemble the interactions into groups corresponding to the number of interactions which would occur during a given pulse. The resulting multiplicity distributions appear more realistic and capture the higher-order multiplets which are a product of multiple reactions occurring during a single accelerator pulse. Plans are underway to gather relevant experimental data to verify and validate the methodology developed and presented here. This capability will enable the simulation of a large number of materials and detector geometries. Analysis of this information will determine the feasibility of using multiplicity distributions as an identification tool for special nuclear material.

  19. Multiple chronic conditions and life expectancy: a life table analysis.

    Science.gov (United States)

    DuGoff, Eva H; Canudas-Romo, Vladimir; Buttorff, Christine; Leff, Bruce; Anderson, Gerard F

    2014-08-01

    The number of people living with multiple chronic conditions is increasing, but we know little about the impact of multimorbidity on life expectancy. We analyze life expectancy in Medicare beneficiaries by number of chronic conditions. A retrospective cohort study using single-decrement period life tables. Medicare fee-for-service beneficiaries (N=1,372,272) aged 67 and older as of January 1, 2008. Our primary outcome measure is life expectancy. We categorize study subjects by sex, race, selected chronic conditions (heart disease, cancer, chronic obstructive pulmonary disease, stroke, and Alzheimer disease), and number of comorbid conditions. Comorbidity was measured as a count of conditions collected by Chronic Conditions Warehouse and the Charlson Comorbidity Index. Life expectancy decreases with each additional chronic condition. A 67-year-old individual with no chronic conditions will live on average 22.6 additional years. A 67-year-old individual with 5 chronic conditions and ≥10 chronic conditions will live 7.7 fewer years and 17.6 fewer years, respectively. The average marginal decline in life expectancy is 1.8 years with each additional chronic condition-ranging from 0.4 fewer years with the first condition to 2.6 fewer years with the sixth condition. These results are consistent by sex and race. We observe differences in life expectancy by selected conditions at 67, but these differences diminish with age and increasing numbers of comorbid conditions. Social Security and Medicare actuaries should account for the growing number of beneficiaries with multiple chronic conditions when determining population projections and trust fund solvency.

  20. Multiple Criteria and Multiple Periods Performance Analysis: The Comparison of North African Railways

    Science.gov (United States)

    Sabri, Karim; Colson, Gérard E.; Mbangala, Augustin M.

    2008-10-01

    Multi-period differences of technical and financial performances are analysed by comparing five North African railways over the period (1990-2004). A first approach is based on the Malmquist DEA TFP index for measuring the total factors productivity change, decomposed into technical efficiency change and technological changes. A multiple criteria analysis is also performed using the PROMETHEE II method and the software ARGOS. These methods provide complementary detailed information, especially by discriminating the technological and management progresses by Malmquist and the two dimensions of performance by Promethee: that are the service to the community and the enterprises performances, often in conflict.

  1. Research and analyze of physical health using multiple regression analysis

    Directory of Open Access Journals (Sweden)

    T. S. Kyi

    2014-01-01

    Full Text Available This paper represents the research which is trying to create a mathematical model of the "healthy people" using the method of regression analysis. The factors are the physical parameters of the person (such as heart rate, lung capacity, blood pressure, breath holding, weight height coefficient, flexibility of the spine, muscles of the shoulder belt, abdominal muscles, squatting, etc.., and the response variable is an indicator of physical working capacity. After performing multiple regression analysis, obtained useful multiple regression models that can predict the physical performance of boys the aged of fourteen to seventeen years. This paper represents the development of regression model for the sixteen year old boys and analyzed results.

  2. Background stratified Poisson regression analysis of cohort data.

    Science.gov (United States)

    Richardson, David B; Langholz, Bryan

    2012-03-01

    Background stratified Poisson regression is an approach that has been used in the analysis of data derived from a variety of epidemiologically important studies of radiation-exposed populations, including uranium miners, nuclear industry workers, and atomic bomb survivors. We describe a novel approach to fit Poisson regression models that adjust for a set of covariates through background stratification while directly estimating the radiation-disease association of primary interest. The approach makes use of an expression for the Poisson likelihood that treats the coefficients for stratum-specific indicator variables as 'nuisance' variables and avoids the need to explicitly estimate the coefficients for these stratum-specific parameters. Log-linear models, as well as other general relative rate models, are accommodated. This approach is illustrated using data from the Life Span Study of Japanese atomic bomb survivors and data from a study of underground uranium miners. The point estimate and confidence interval obtained from this 'conditional' regression approach are identical to the values obtained using unconditional Poisson regression with model terms for each background stratum. Moreover, it is shown that the proposed approach allows estimation of background stratified Poisson regression models of non-standard form, such as models that parameterize latency effects, as well as regression models in which the number of strata is large, thereby overcoming the limitations of previously available statistical software for fitting background stratified Poisson regression models.

  3. Background stratified Poisson regression analysis of cohort data

    International Nuclear Information System (INIS)

    Richardson, David B.; Langholz, Bryan

    2012-01-01

    Background stratified Poisson regression is an approach that has been used in the analysis of data derived from a variety of epidemiologically important studies of radiation-exposed populations, including uranium miners, nuclear industry workers, and atomic bomb survivors. We describe a novel approach to fit Poisson regression models that adjust for a set of covariates through background stratification while directly estimating the radiation-disease association of primary interest. The approach makes use of an expression for the Poisson likelihood that treats the coefficients for stratum-specific indicator variables as 'nuisance' variables and avoids the need to explicitly estimate the coefficients for these stratum-specific parameters. Log-linear models, as well as other general relative rate models, are accommodated. This approach is illustrated using data from the Life Span Study of Japanese atomic bomb survivors and data from a study of underground uranium miners. The point estimate and confidence interval obtained from this 'conditional' regression approach are identical to the values obtained using unconditional Poisson regression with model terms for each background stratum. Moreover, it is shown that the proposed approach allows estimation of background stratified Poisson regression models of non-standard form, such as models that parameterize latency effects, as well as regression models in which the number of strata is large, thereby overcoming the limitations of previously available statistical software for fitting background stratified Poisson regression models. (orig.)

  4. Sparse Group Penalized Integrative Analysis of Multiple Cancer Prognosis Datasets

    Science.gov (United States)

    Liu, Jin; Huang, Jian; Xie, Yang; Ma, Shuangge

    2014-01-01

    SUMMARY In cancer research, high-throughput profiling studies have been extensively conducted, searching for markers associated with prognosis. Because of the “large d, small n” characteristic, results generated from the analysis of a single dataset can be unsatisfactory. Recent studies have shown that integrative analysis, which simultaneously analyzes multiple datasets, can be more effective than single-dataset analysis and classic meta-analysis. In most of existing integrative analysis, the homogeneity model has been assumed, which postulates that different datasets share the same set of markers. Several approaches have been designed to reinforce this assumption. In practice, different datasets may differ in terms of patient selection criteria, profiling techniques, and many other aspects. Such differences may make the homogeneity model too restricted. In this study, we assume the heterogeneity model, under which different datasets are allowed to have different sets of markers. With multiple cancer prognosis datasets, we adopt the AFT (accelerated failure time) model to describe survival. This model may have the lowest computational cost among popular semiparametric survival models. For marker selection, we adopt a sparse group MCP (minimax concave penalty) approach. This approach has an intuitive formulation and can be computed using an effective group coordinate descent algorithm. Simulation study shows that it outperforms the existing approaches under both the homogeneity and heterogeneity models. Data analysis further demonstrates the merit of heterogeneity model and proposed approach. PMID:23938111

  5. Analysis of multiple spurions and associated circuits in Cofrentes

    International Nuclear Information System (INIS)

    Molina, J. J.; Celaya, M. A.

    2015-01-01

    The article describes the process followed by the Cofrentes Nuclear Power Plant (CNC) to conduct the analysis of multiple spurious in compliance with regulatory standards IS-30 rev 1 and CSN Safety Guide 1.19 based on the recommendations of the NEI-00-01 Guidance for Post-fire Safe Shutdown Circuit and NUREG/CR-6850. Fire PRA Methodology for Nuclear Power Facilities. (Author)

  6. Convergence Analysis for the Multiplicative Schwarz Preconditioned Inexact Newton Algorithm

    KAUST Repository

    Liu, Lulu

    2016-10-26

    The multiplicative Schwarz preconditioned inexact Newton (MSPIN) algorithm, based on decomposition by field type rather than by subdomain, was recently introduced to improve the convergence of systems with unbalanced nonlinearities. This paper provides a convergence analysis of the MSPIN algorithm. Under reasonable assumptions, it is shown that MSPIN is locally convergent, and desired superlinear or even quadratic convergence can be obtained when the forcing terms are picked suitably.

  7. Convergence Analysis for the Multiplicative Schwarz Preconditioned Inexact Newton Algorithm

    KAUST Repository

    Liu, Lulu; Keyes, David E.

    2016-01-01

    The multiplicative Schwarz preconditioned inexact Newton (MSPIN) algorithm, based on decomposition by field type rather than by subdomain, was recently introduced to improve the convergence of systems with unbalanced nonlinearities. This paper provides a convergence analysis of the MSPIN algorithm. Under reasonable assumptions, it is shown that MSPIN is locally convergent, and desired superlinear or even quadratic convergence can be obtained when the forcing terms are picked suitably.

  8. Methodological issues underlying multiple decrement life table analysis.

    Science.gov (United States)

    Mode, C J; Avery, R C; Littman, G S; Potter, R G

    1977-02-01

    In this paper, the actuarial method of multiple decrement life table analysis of censored, longitudinal data is examined. The discussion is organized in terms of the first segment of usage of an intrauterine device. Weaknesses of the actuarial approach are pointed out, and an alternative approach, based on the classical model of competing risks, is proposed. Finally, the actuarial and the alternative method of analyzing censored data are compared, using data from the Taichung Medical Study on Intrauterine Devices.

  9. mma: An R Package for Mediation Analysis with Multiple Mediators

    OpenAIRE

    Qingzhao Yu; Bin Li

    2017-01-01

    Mediation refers to the effect transmitted by mediators that intervene in the relationship between an exposure and a response variable. Mediation analysis has been broadly studied in many fields. However, it remains a challenge for researchers to consider complicated associations among variables and to differentiate individual effects from multiple mediators. [1] proposed general definitions of mediation effects that were adaptable to all different types of response (categorical or continuous...

  10. Inherited predisposition to preeclampsia: Analysis of the Aberdeen intergenerational cohort.

    Science.gov (United States)

    Ayorinde, Abimbola A; Bhattacharya, Sohinee

    2017-04-01

    To assess the magnitude of familial risk of preeclampsia and gestational hypertension in women born of a preeclamptic pregnancy and those born of pregnancy complicated by gestational hypertension while accounting for other risk factors. An intergenerational dataset was extracted from the Aberdeen Maternity and Neonatal Databank (AMND) which records all pregnancy and delivery details occurring in Aberdeen, Scotland since 1950. The analysis included all nulliparous women whose mothers' records at their births are also recorded in the AMND. Multinomial logistic regression was used to assess the risk of having preeclampsia or gestational hypertension based on maternal history of preeclampsia or gestational hypertension. There were 17302 nulliparous women included, of whom 1057(6.1%) had preeclampsia while 4098(23.7%) had gestational hypertension. Furthermore, 424(2.5%) and 2940(17.0%) had maternal history of preeclampsia and gestational hypertension respectively. The risk of preeclampsia was higher in women who were born of pregnancies complicated by preeclampsia (adjusted RRR 2.55 95% CI 1.87-3.47). This was higher than the risk observed in women whose mothers had gestational hypertension (adjusted RRR 1.44 95% CI 1.23-1.69). Conversely, the risk of gestational hypertension was similar in those who were born of preeclamptic pregnancies (adjusted RRR 1.37 95% CI 1.09-1.71) and those whose mothers had gestational hypertension (adjusted RRR 1.36 95% CI 1.24-1.49). There was a dose response effect in the inheritance pattern of preeclampsia with the highest risk in women born of preeclamptic pregnancies. Gestational hypertension showed similar increased risk with maternal gestational hypertension and preeclampsia. Copyright © 2017 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

  11. Multivariant design and multiple criteria analysis of building refurbishments

    Energy Technology Data Exchange (ETDEWEB)

    Kaklauskas, A.; Zavadskas, E. K.; Raslanas, S. [Faculty of Civil Engineering, Vilnius Gediminas Technical University, Vilnius (Lithuania)

    2005-07-01

    In order to design and realize an efficient building refurbishment, it is necessary to carry out an exhaustive investigation of all solutions that form it. The efficiency level of the considered building's refurbishment depends on a great many of factors, including: cost of refurbishment, annual fuel economy after refurbishment, tentative pay-back time, harmfulness to health of the materials used, aesthetics, maintenance properties, functionality, comfort, sound insulation and longevity, etc. Solutions of an alternative character allow for a more rational and realistic assessment of economic, ecological, legislative, climatic, social and political conditions, traditions and for better the satisfaction of customer requirements. They also enable one to cut down on refurbishment costs. In carrying out the multivariant design and multiple criteria analysis of a building refurbishment much data was processed and evaluated. Feasible alternatives could be as many as 100,000. How to perform a multivariant design and multiple criteria analysis of alternate alternatives based on the enormous amount of information became the problem. Method of multivariant design and multiple criteria of a building refurbishment's analysis were developed by the authors to solve the above problems. In order to demonstrate the developed method, a practical example is presented in this paper. (author)

  12. Robustness Analysis of Real Network Topologies Under Multiple Failure Scenarios

    DEFF Research Database (Denmark)

    Manzano, M.; Marzo, J. L.; Calle, E.

    2012-01-01

    on topological characteristics. Recently approaches also consider the services supported by such networks. In this paper we carry out a robustness analysis of five real backbone telecommunication networks under defined multiple failure scenarios, taking into account the consequences of the loss of established......Nowadays the ubiquity of telecommunication networks, which underpin and fulfill key aspects of modern day living, is taken for granted. Significant large-scale failures have occurred in the last years affecting telecommunication networks. Traditionally, network robustness analysis has been focused...... connections. Results show which networks are more robust in response to a specific type of failure....

  13. Functional analysis screening for multiple topographies of problem behavior.

    Science.gov (United States)

    Bell, Marlesha C; Fahmie, Tara A

    2018-04-23

    The current study evaluated a screening procedure for multiple topographies of problem behavior in the context of an ongoing functional analysis. Experimenters analyzed the function of a topography of primary concern while collecting data on topographies of secondary concern. We used visual analysis to predict the function of secondary topographies and a subsequent functional analysis to test those predictions. Results showed that a general function was accurately predicted for five of six (83%) secondary topographies. A specific function was predicted and supported for a subset of these topographies. The experimenters discuss the implication of these results for clinicians who have limited time for functional assessment. © 2018 Society for the Experimental Analysis of Behavior.

  14. Differential factors associated with challenge-proven food allergy phenotypes in a population cohort of infants: a latent class analysis.

    Science.gov (United States)

    Peters, R L; Allen, K J; Dharmage, S C; Lodge, C J; Koplin, J J; Ponsonby, A-L; Wake, M; Lowe, A J; Tang, M L K; Matheson, M C; Gurrin, L C

    2015-05-01

    Food allergy, eczema and wheeze are early manifestations of allergic disease and commonly co-occur in infancy although their interrelationship is not well understood. Data from population studies are essential to determine whether there are differential drivers of multi-allergy phenotypes. We aimed to define phenotypes and risk factors of allergic disease using latent class analysis (LCA). The HealthNuts study is a prospective, population-based cohort of 5276 12-month-old infants in Melbourne, Australia. LCA was performed using the following baseline data collected at age 12 months: food sensitization (skin prick test ≥ 2 mm) and allergy (oral food challenge) to egg, peanut and sesame; early (food-sensitized eczema (16%), single egg allergy (9%), multiple food allergies (predominantly peanut) (3%) and multiple food allergies (predominantly egg) (2%). Compared to the baseline group of no allergic disease, shared risk factors for all allergic phenotypes were parents born overseas (particularly Asia), delayed introduction of egg, male gender (except for single egg allergy) and family history of allergic disease, whilst exposure to pet dogs was protective for all phenotypes. Other factors including filaggrin mutations, vitamin D and the presence of older siblings differed by phenotype. Multiple outcomes in infancy can be used to determine five distinct allergy phenotypes at the population level, which have both shared and separate risk factors suggesting differential mechanisms of disease. © 2014 John Wiley & Sons Ltd.

  15. Common pitfalls in statistical analysis: The perils of multiple testing

    Science.gov (United States)

    Ranganathan, Priya; Pramesh, C. S.; Buyse, Marc

    2016-01-01

    Multiple testing refers to situations where a dataset is subjected to statistical testing multiple times - either at multiple time-points or through multiple subgroups or for multiple end-points. This amplifies the probability of a false-positive finding. In this article, we look at the consequences of multiple testing and explore various methods to deal with this issue. PMID:27141478

  16. mma: An R Package for Mediation Analysis with Multiple Mediators

    Directory of Open Access Journals (Sweden)

    Qingzhao Yu

    2017-04-01

    Full Text Available Mediation refers to the effect transmitted by mediators that intervene in the relationship between an exposure and a response variable. Mediation analysis has been broadly studied in many fields. However, it remains a challenge for researchers to consider complicated associations among variables and to differentiate individual effects from multiple mediators. [1] proposed general definitions of mediation effects that were adaptable to all different types of response (categorical or continuous, exposure, or mediation variables. With these definitions, multiple mediators of different types can be considered simultaneously, and the indirect effects carried by individual mediators can be separated from the total effect. Moreover, the derived mediation analysis can be performed with general predictive models. That is, the relationships among variables can be modeled using not only generalized linear models but also nonparametric models such as the Multiple Additive Regression Trees. Therefore, more complicated variable transformations and interactions can be considered in analyzing the mediation effects. The proposed method is realized by the R package 'mma'. We illustrate in this paper the proposed method and how to use 'mma' to estimate mediation effects and make inferences.

  17. A Historical Cohort Study on the Efficacy of Glucocorticoids and Riboflavin Among Patients with Late-onset Multiple Acyl-CoA Dehydrogenase Deficiency

    Institute of Scientific and Technical Information of China (English)

    Xin-Yi Liu; Zhi-Qiang Wang; Dan-Ni Wang; Min-Ting Lin; Ning Wang

    2016-01-01

    Background:Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is the most common type of lipid storage myopathies in China.Most patients with late-onset MADD are well responsive to riboflavin.Up to now,these patients are often treated with glucocorticoids as the first-line drug because they are misdiagnosed as polymyositis without muscle biopsy or gene analysis.Although glucocorticoids seem to improve the fatty acid metabolism of late-onset MADD,the objective evaluation of their rationalization on this disorder and comparison with riboflavin treatment are unknown.Methods:We performed a historical cohort study on the efficacy of the two drugs among 45 patients with late-onset MADD,who were divided into glucocorticoids group and riboflavin group.Detailed clinical information of baseline and 1-month follow-up were collected.Results:After 1-month treatment,a dramatic improvement of muscle strength was found in riboflavin group (P < 0.05).There was no significant difference in muscle enzymes between the two groups.Significantly,the number of patients with full recovery in glucocorticoids group was less than the number in riboflavin group (P < 0.05).On the other hand,almost half of the patients in riboflavin group still presented high-level muscle enzymes and weak muscle strength after 1-month riboflavin treatment,meaning that 1-month treatment duration maybe insufficient and patients should keep on riboflavin supplement for a longer time.Conclusions:Our results provide credible evidences that the overall efficacy of riboflavin is superior to glucocorticoids,and a longer duration of riboflavin treatment is necessary for patients with late-onset MADD.

  18. Ovarian response to 150 µg corifollitropin alfa in a GnRH-antagonist multiple-dose protocol: a prospective cohort study.

    Science.gov (United States)

    Lerman, Tamara; Depenbusch, Marion; Schultze-Mosgau, Askan; von Otte, Soeren; Scheinhardt, Markus; Koenig, Inke; Kamischke, Axel; Macek, Milan; Schwennicke, Arne; Segerer, Sabine; Griesinger, Georg

    2017-05-01

    The incidence of low (18 oocytes) ovarian response to 150 µg corifollitropin alfa in relation to anti-Müllerian hormone (AMH) and other biomarkers was studied in a multi-centre (n = 5), multi-national, prospective, investigator-initiated, observational cohort study. Infertile women (n = 212), body weight >60 kg, underwent controlled ovarian stimulation in a gonadotrophin-releasing hormone-antagonist multiple-dose protocol. Demographic, sonographic and endocrine parameters were prospectively assessed on cycle day 2 or 3 of a spontaneous menstruation before the administration of 150 µg corifollitropin alfa. Serum AMH showed the best correlation with the number of oocytes obtained among all predictor variables. In receiver-operating characteristic analysis, AMH at a threshold of 0.91 ng/ml showed a sensitivity of 82.4%, specificity of 82.4%, positive predictive value 52.9%and negative predictive value 95.1% for predicting low response (area under the curve [AUC], 95% CI; P-value: 0.853, 0.769-0.936; <0.0001). For predicting high response, the optimal threshold for AMH was 2.58 ng/ml, relating to a sensitivity of 80.0%, specificity 82.1%, positive predictive value 42.5% and negative predictive value 96.1% (AUC, 95% CI; P-value: 0.871, 0.787-0.955; <0.0001). In conclusion, patients with serum AMH concentrations between approximately 0.9 and 2.6 ng/ml were unlikely to show extremes of response. Copyright © 2017. Published by Elsevier Ltd.

  19. Automatic visual tracking and social behaviour analysis with multiple mice.

    Directory of Open Access Journals (Sweden)

    Luca Giancardo

    Full Text Available Social interactions are made of complex behavioural actions that might be found in all mammalians, including humans and rodents. Recently, mouse models are increasingly being used in preclinical research to understand the biological basis of social-related pathologies or abnormalities. However, reliable and flexible automatic systems able to precisely quantify social behavioural interactions of multiple mice are still missing. Here, we present a system built on two components. A module able to accurately track the position of multiple interacting mice from videos, regardless of their fur colour or light settings, and a module that automatically characterise social and non-social behaviours. The behavioural analysis is obtained by deriving a new set of specialised spatio-temporal features from the tracker output. These features are further employed by a learning-by-example classifier, which predicts for each frame and for each mouse in the cage one of the behaviours learnt from the examples given by the experimenters. The system is validated on an extensive set of experimental trials involving multiple mice in an open arena. In a first evaluation we compare the classifier output with the independent evaluation of two human graders, obtaining comparable results. Then, we show the applicability of our technique to multiple mice settings, using up to four interacting mice. The system is also compared with a solution recently proposed in the literature that, similarly to us, addresses the problem with a learning-by-examples approach. Finally, we further validated our automatic system to differentiate between C57B/6J (a commonly used reference inbred strain and BTBR T+tf/J (a mouse model for autism spectrum disorders. Overall, these data demonstrate the validity and effectiveness of this new machine learning system in the detection of social and non-social behaviours in multiple (>2 interacting mice, and its versatility to deal with different

  20. Mode Shape Analysis of Multiple Cracked Functionally Graded Timoshenko Beams

    Directory of Open Access Journals (Sweden)

    Tran Van Lien

    Full Text Available Abstract The present paper addresses free vibration of multiple cracked Timoshenko beams made of Functionally Graded Material (FGM. Cracks are modeled by rotational spring of stiffness calculated from the crack depth and material properties vary according to the power law throughout the beam thickness. Governing equations for free vibration of the beam are formulated with taking into account actual position of the neutral plane. The obtained frequency equation and mode shapes are used for analysis of the beam mode shapes in dependence on the material and crack parameters. Numerical results validate usefulness of the proposed herein theory and show that mode shapes are good indication for detecting multiple cracks in Timoshenko FGM beams.

  1. Multifractal detrended fluctuation analysis of analog random multiplicative processes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, L.B.M.; Vermelho, M.V.D. [Instituto de Fisica, Universidade Federal de Alagoas, Maceio - AL, 57072-970 (Brazil); Lyra, M.L. [Instituto de Fisica, Universidade Federal de Alagoas, Maceio - AL, 57072-970 (Brazil)], E-mail: marcelo@if.ufal.br; Viswanathan, G.M. [Instituto de Fisica, Universidade Federal de Alagoas, Maceio - AL, 57072-970 (Brazil)

    2009-09-15

    We investigate non-Gaussian statistical properties of stationary stochastic signals generated by an analog circuit that simulates a random multiplicative process with weak additive noise. The random noises are originated by thermal shot noise and avalanche processes, while the multiplicative process is generated by a fully analog circuit. The resulting signal describes stochastic time series of current interest in several areas such as turbulence, finance, biology and environment, which exhibit power-law distributions. Specifically, we study the correlation properties of the signal by employing a detrended fluctuation analysis and explore its multifractal nature. The singularity spectrum is obtained and analyzed as a function of the control circuit parameter that tunes the asymptotic power-law form of the probability distribution function.

  2. Data analysis and pattern recognition in multiple databases

    CERN Document Server

    Adhikari, Animesh; Pedrycz, Witold

    2014-01-01

    Pattern recognition in data is a well known classical problem that falls under the ambit of data analysis. As we need to handle different data, the nature of patterns, their recognition and the types of data analyses are bound to change. Since the number of data collection channels increases in the recent time and becomes more diversified, many real-world data mining tasks can easily acquire multiple databases from various sources. In these cases, data mining becomes more challenging for several essential reasons. We may encounter sensitive data originating from different sources - those cannot be amalgamated. Even if we are allowed to place different data together, we are certainly not able to analyse them when local identities of patterns are required to be retained. Thus, pattern recognition in multiple databases gives rise to a suite of new, challenging problems different from those encountered before. Association rule mining, global pattern discovery, and mining patterns of select items provide different...

  3. National cohort study of absolute risk and age-specific incidence of multiple adverse outcomes between adolescence and early middle age.

    Science.gov (United States)

    Mok, Pearl L H; Antonsen, Sussie; Pedersen, Carsten Bøcker; Appleby, Louis; Shaw, Jenny; Webb, Roger T

    2015-09-19

    Psychiatric illness, substance misuse, suicidality, criminality and premature death represent major public health challenges that afflict a sizeable proportion of young people. However, studies of multiple adverse outcomes in the same cohort at risk are rare. In a national Danish cohort we estimated sex- and age-specific incidence rates and absolute risks of these outcomes between adolescence and early middle age. Using interlinked registers, persons born in Denmark 1966-1996 were followed from their 15(th) until 40(th) birthday or December 2011 (N = 2,070,904). We estimated sex- and age-specific incidence rates of nine adverse outcomes, in three main categories: Premature mortality (all-causes, suicide, accident); Psychiatric morbidity (any mental illness diagnosis, suicide attempt, alcohol or drug misuse disorder); Criminality (violent offending, receiving custodial sentence, driving under influence of alcohol or drugs). Cumulative incidences were also calculated using competing risk survival analyses. For cohort members alive on their 15(th) birthday, the absolute risks of dying by age 40 were 1.99 % for males [95 % confidence interval (CI) 1.95-2.03 %] and 0.85 % for females (95 % CI 0.83-0.88 %). The risks of substance misuse and criminality were also much higher for males, especially younger males, than for females. Specifically, the risk of a first conviction for a violent offence was highest amongst males aged below 20. Females, however, were more likely than males to have a hospital-treated psychiatric disorder. By age 40, 13.25 % of females (95 % CI 13.16-13.33 %) and 9.98 % of males (95 % CI 9.91-10.06 %) had been treated. Women aged below 25 were also more likely than men to first attempt suicide, but this pattern was reversed beyond this age. The greatest gender differentials in incidence rates were in criminality outcomes. This is the first comprehensive assessment of the incidence rates and absolute risks of these multiple adverse outcomes

  4. A new approach to age-period-cohort analysis using partial least squares regression: the trend in blood pressure in the Glasgow Alumni cohort.

    Directory of Open Access Journals (Sweden)

    Yu-Kang Tu

    2011-04-01

    Full Text Available Due to a problem of identification, how to estimate the distinct effects of age, time period and cohort has been a controversial issue in the analysis of trends in health outcomes in epidemiology. In this study, we propose a novel approach, partial least squares (PLS analysis, to separate the effects of age, period, and cohort. Our example for illustration is taken from the Glasgow Alumni cohort. A total of 15,322 students (11,755 men and 3,567 women received medical screening at the Glasgow University between 1948 and 1968. The aim is to investigate the secular trends in blood pressure over 1925 and 1950 while taking into account the year of examination and age at examination. We excluded students born before 1925 or aged over 25 years at examination and those with missing values in confounders from the analyses, resulting in 12,546 and 12,516 students for analysis of systolic and diastolic blood pressure, respectively. PLS analysis shows that both systolic and diastolic blood pressure increased with students' age, and students born later had on average lower blood pressure (SBP: -0.17 mmHg/per year [95% confidence intervals: -0.19 to -0.15] for men and -0.25 [-0.28 to -0.22] for women; DBP: -0.14 [-0.15 to -0.13] for men; -0.09 [-0.11 to -0.07] for women. PLS also shows a decreasing trend in blood pressure over the examination period. As identification is not a problem for PLS, it provides a flexible modelling strategy for age-period-cohort analysis. More emphasis is then required to clarify the substantive and conceptual issues surrounding the definitions and interpretations of age, period and cohort effects.

  5. Multiple predictor smoothing methods for sensitivity analysis: Description of techniques

    International Nuclear Information System (INIS)

    Storlie, Curtis B.; Helton, Jon C.

    2008-01-01

    The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described: (i) locally weighted regression (LOESS), (ii) additive models, (iii) projection pursuit regression, and (iv) recursive partitioning regression. Then, in the second and concluding part of this presentation, the indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present

  6. Multiple predictor smoothing methods for sensitivity analysis: Example results

    International Nuclear Information System (INIS)

    Storlie, Curtis B.; Helton, Jon C.

    2008-01-01

    The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described in the first part of this presentation: (i) locally weighted regression (LOESS), (ii) additive models, (iii) projection pursuit regression, and (iv) recursive partitioning regression. In this, the second and concluding part of the presentation, the indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present

  7. Two-locus linkage analysis in multiple sclerosis (MS)

    Energy Technology Data Exchange (ETDEWEB)

    Tienari, P.J. (National Public Health Institute, Helsinki (Finland) Univ. of Helsinki (Finland)); Terwilliger, J.D.; Ott, J. (Columbia Univ., New York (United States)); Palo, J. (Univ. of Helsinki (Finland)); Peltonen, L. (National Public Health Institute, Helsinki (Finland))

    1994-01-15

    One of the major challenges in genetic linkage analyses is the study of complex diseases. The authors demonstrate here the use of two-locus linkage analysis in multiple sclerosis (MS), a multifactorial disease with a complex mode of inheritance. In a set of Finnish multiplex families, they have previously found evidence for linkage between MS susceptibility and two independent loci, the myelin basic protein gene (MBP) on chromosome 18 and the HLA complex on chromosome 6. This set of families provides a unique opportunity to perform linkage analysis conditional on two loci contributing to the disease. In the two-trait-locus/two-marker-locus analysis, the presence of another disease locus is parametrized and the analysis more appropriately treats information from the unaffected family member than single-disease-locus analysis. As exemplified here in MS, the two-locus analysis can be a powerful method for investigating susceptibility loci in complex traits, best suited for analysis of specific candidate genes, or for situations in which preliminary evidence for linkage already exists or is suggested. 41 refs., 6 tabs.

  8. Rasch analysis of the Multiple Sclerosis Impact Scale (MSIS-29

    Directory of Open Access Journals (Sweden)

    Misajon Rose

    2009-06-01

    Full Text Available Abstract Background Multiple Sclerosis (MS is a degenerative neurological disease that causes impairments, including spasticity, pain, fatigue, and bladder dysfunction, which negatively impact on quality of life. The Multiple Sclerosis Impact Scale (MSIS-29 is a disease-specific health-related quality of life (HRQoL instrument, developed using the patient's perspective on disease impact. It consists of two subscales assessing the physical (MSIS-29-PHYS and psychological (MSIS-29-PSYCH impact of MS. Although previous studies have found support for the psychometric properties of the MSIS-29 using traditional methods of scale evaluation, the scale has not been subjected to a detailed Rasch analysis. Therefore, the objective of this study was to use Rasch analysis to assess the internal validity of the scale, and its response format, item fit, targeting, internal consistency and dimensionality. Methods Ninety-two persons with definite MS residing in the community were recruited from a tertiary hospital database. Patients completed the MSIS-29 as part of a larger study. Rasch analysis was undertaken to assess the psychometric properties of the MSIS-29. Results Rasch analysis showed overall support for the psychometric properties of the two MSIS-29 subscales, however it was necessary to reduce the response format of the MSIS-29-PHYS to a 3-point response scale. Both subscales were unidimensional, had good internal consistency, and were free from item bias for sex and age. Dimensionality testing indicated it was not appropriate to combine the two subscales to form a total MSIS score. Conclusion In this first study to use Rasch analysis to fully assess the psychometric properties of the MSIS-29 support was found for the two subscales but not for the use of the total scale. Further use of Rasch analysis on the MSIS-29 in larger and broader samples is recommended to confirm these findings.

  9. Rasch analysis of the Multiple Sclerosis Impact Scale (MSIS-29)

    Science.gov (United States)

    Ramp, Melina; Khan, Fary; Misajon, Rose Anne; Pallant, Julie F

    2009-01-01

    Background Multiple Sclerosis (MS) is a degenerative neurological disease that causes impairments, including spasticity, pain, fatigue, and bladder dysfunction, which negatively impact on quality of life. The Multiple Sclerosis Impact Scale (MSIS-29) is a disease-specific health-related quality of life (HRQoL) instrument, developed using the patient's perspective on disease impact. It consists of two subscales assessing the physical (MSIS-29-PHYS) and psychological (MSIS-29-PSYCH) impact of MS. Although previous studies have found support for the psychometric properties of the MSIS-29 using traditional methods of scale evaluation, the scale has not been subjected to a detailed Rasch analysis. Therefore, the objective of this study was to use Rasch analysis to assess the internal validity of the scale, and its response format, item fit, targeting, internal consistency and dimensionality. Methods Ninety-two persons with definite MS residing in the community were recruited from a tertiary hospital database. Patients completed the MSIS-29 as part of a larger study. Rasch analysis was undertaken to assess the psychometric properties of the MSIS-29. Results Rasch analysis showed overall support for the psychometric properties of the two MSIS-29 subscales, however it was necessary to reduce the response format of the MSIS-29-PHYS to a 3-point response scale. Both subscales were unidimensional, had good internal consistency, and were free from item bias for sex and age. Dimensionality testing indicated it was not appropriate to combine the two subscales to form a total MSIS score. Conclusion In this first study to use Rasch analysis to fully assess the psychometric properties of the MSIS-29 support was found for the two subscales but not for the use of the total scale. Further use of Rasch analysis on the MSIS-29 in larger and broader samples is recommended to confirm these findings. PMID:19545445

  10. Lymphocytes with multiple chromosomal damages in a large cohort of West Siberia residents: Results of long-term monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Druzhinin, Vladimir [Kemerovo State University, Kemerovo (Russian Federation); Federal State Budget Scientific Institution «The Federal Research Center of Coal and Coal Chemistry of Siberian Branch of the Russian Academy of Sciences», Kemerovo (Russian Federation); Bakanova, Maria [Federal State Budget Scientific Institution «The Federal Research Center of Coal and Coal Chemistry of Siberian Branch of the Russian Academy of Sciences», Kemerovo (Russian Federation); Fucic, Aleksandra, E-mail: afucic@imi.hr [Institute for Medical Research and Occupational Health, Zagreb (Croatia); Golovina, Tatiana [Kemerovo State University, Kemerovo (Russian Federation); Savchenko, Yana [Federal State Budget Scientific Institution «The Federal Research Center of Coal and Coal Chemistry of Siberian Branch of the Russian Academy of Sciences», Kemerovo (Russian Federation); Sinitsky, Maxim; Volobaev, Valentin [Kemerovo State University, Kemerovo (Russian Federation)

    2016-02-15

    Highlights: • Study reports RC frequency in lymphocytes in the group of 3242 subjects. • The highest RC frequency was present in children environmentally exposed to radon. • In 85% of RCs double minutes were observed. • Results suggests that radon may be the leading factors causing RC. • RC may be a candidate biomarker for exposure to α-emitters. - Abstract: Cells with specific multiple chromosome aberrations, defined as rogue cells (RC) have been described in different populations, predominantly those exposed to radiation. The frequency, etiology and related health risks have still not been elucidated due to their low frequency of occurrences and rarely performed studies. This study reports RC frequency using chromosome aberration (CA) assay in peripheral lymphocytes in the group of 3242 subjects, during a 30-year long follow-up study in a general rural and urban population, children environmentally exposed to radon, occupationally exposed population and lung cancer patients from the Kemerovo region (Siberia, Russian Federation). Results show that the highest RC frequency was present in children environmentally exposed to radon and the lowest in the general urban population. Total frequency of CA did not correlate with frequency of RC. Genotoxic analysis of air and water samples excluded anthropogenic pollution as a possible cause of genome damage and RC frequency. In 85% of RCs, double minutes, observed in a large number of human tumors, were present. Results of CA analysis suggested that radon and its decay products (alpha-emitters) were the leading factors causing RC in subjects exposed to high LET radiation. Thus, RC may be a candidate biomarker for exposure to this type of radiation.

  11. Multiple murder and criminal careers: a latent class analysis of multiple homicide offenders.

    Science.gov (United States)

    Vaughn, Michael G; DeLisi, Matt; Beaver, Kevin M; Howard, Matthew O

    2009-01-10

    To construct an empirically rigorous typology of multiple homicide offenders (MHOs). The current study conducted latent class analysis of the official records of 160 MHOs sampled from eight states to evaluate their criminal careers. A 3-class solution best fit the data (-2LL=-1123.61, Bayesian Information Criterion (BIC)=2648.15, df=81, L(2)=1179.77). Class 1 (n=64, class assignment probability=.999) was the low-offending group marked by little criminal record and delayed arrest onset. Class 2 (n=51, class assignment probability=.957) was the severe group that represents the most violent and habitual criminals. Class 3 (n=45, class assignment probability=.959) was the moderate group whose offending careers were similar to Class 2. A sustained criminal career with involvement in versatile forms of crime was observed for two of three classes of MHOs. Linkages to extant typologies and recommendations for additional research that incorporates clinical constructs are proffered.

  12. Monitoring urban greenness dynamics using multiple endmember spectral mixture analysis.

    Directory of Open Access Journals (Sweden)

    Muye Gan

    Full Text Available Urban greenness is increasingly recognized as an essential constituent of the urban environment and can provide a range of services and enhance residents' quality of life. Understanding the pattern of urban greenness and exploring its spatiotemporal dynamics would contribute valuable information for urban planning. In this paper, we investigated the pattern of urban greenness in Hangzhou, China, over the past two decades using time series Landsat-5 TM data obtained in 1990, 2002, and 2010. Multiple endmember spectral mixture analysis was used to derive vegetation cover fractions at the subpixel level. An RGB-vegetation fraction model, change intensity analysis and the concentric technique were integrated to reveal the detailed, spatial characteristics and the overall pattern of change in the vegetation cover fraction. Our results demonstrated the ability of multiple endmember spectral mixture analysis to accurately model the vegetation cover fraction in pixels despite the complex spectral confusion of different land cover types. The integration of multiple techniques revealed various changing patterns in urban greenness in this region. The overall vegetation cover has exhibited a drastic decrease over the past two decades, while no significant change occurred in the scenic spots that were studied. Meanwhile, a remarkable recovery of greenness was observed in the existing urban area. The increasing coverage of small green patches has played a vital role in the recovery of urban greenness. These changing patterns were more obvious during the period from 2002 to 2010 than from 1990 to 2002, and they revealed the combined effects of rapid urbanization and greening policies. This work demonstrates the usefulness of time series of vegetation cover fractions for conducting accurate and in-depth studies of the long-term trajectories of urban greenness to obtain meaningful information for sustainable urban development.

  13. Electrocardiographic PR prolongation and atrial fibrillation risk: a meta-analysis of prospective cohort studies.

    Science.gov (United States)

    Cheng, Min; Lu, Xiangfeng; Huang, Jianfeng; Zhang, Shu; Gu, Dongfeng

    2015-01-01

    Electrocardiographic PR interval prolongation is considered a benign condition, but recent studies have challenged the notion by demonstrating that prolonged PR interval is associated with an increased risk of atrial fibrillation (AF). The purpose of this study was to perform a meta-analysis of prospective cohort studies to evaluate the evidence supporting an association of prolonged PR interval with AF incidence. We searched the MEDLINE and EMBASE database (from inception to May 2014) supplemented by manual searches of references of relevant retrieved articles. Prospective cohort studies were included with hazard ratio (HR) of prolonged PR interval for incident AF. The search strategy yielded 6 cohort studies meeting eligibility criteria. A total of 328,932 participants were included, with 14,191 participants suffering from AF during follow-up. Pooled HRs of prolonged PR interval for incident AF was 1.30 (95% CI: 1.13 to 1.49) using random-effect model (I(2) = 30%). There was a significant difference of combined HRs between studies with and without adjustment for taking of AV nodal blocking agents in subgroup analysis. Sensitivity analysis supported the robustness of the results. Prolonged PR interval is not a totally benign condition but an independent risk factor for AF incidence. The mechanisms underlying the association of prolonged PR interval with AF incidence need further research. © 2014 Wiley Periodicals, Inc.

  14. Analysis of underlying and multiple-cause mortality data.

    Science.gov (United States)

    Moussa, M A; El Sayed, A M; Sugathan, T N; Khogali, M M; Verma, D

    1992-01-01

    "A variety of life table models were used for the analysis of the (1984-86) Kuwaiti cause-specific mortality data. These models comprised total mortality, multiple-decrement, cause-elimination, cause-delay and disease dependency. The models were illustrated by application to a set of four chronic diseases: hypertensive, ischaemic heart, cerebrovascular and diabetes mellitus. The life table methods quantify the relative weights of different diseases as hazards to mortality after adjustment for other causes. They can also evaluate the extent of dependency between underlying cause of death and other causes mentioned on [the] death certificate using an extended underlying-cause model." (SUMMARY IN FRE AND ITA) excerpt

  15. Retinal layer segmentation in multiple sclerosis: a systematic review and meta-analysis.

    Science.gov (United States)

    Petzold, Axel; Balcer, Laura J; Calabresi, Peter A; Costello, Fiona; Frohman, Teresa C; Frohman, Elliot M; Martinez-Lapiscina, Elena H; Green, Ari J; Kardon, Randy; Outteryck, Olivier; Paul, Friedemann; Schippling, Sven; Vermersch, Patrik; Villoslada, Pablo; Balk, Lisanne J

    2017-10-01

    Structural retinal imaging biomarkers are important for early recognition and monitoring of inflammation and neurodegeneration in multiple sclerosis. With the introduction of spectral domain optical coherence tomography (SD-OCT), supervised automated segmentation of individual retinal layers is possible. We aimed to investigate which retinal layers show atrophy associated with neurodegeneration in multiple sclerosis when measured with SD-OCT. In this systematic review and meta-analysis, we searched for studies in which SD-OCT was used to look at the retina in people with multiple sclerosis with or without optic neuritis in PubMed, Web of Science, and Google Scholar between Nov 22, 1991, and April 19, 2016. Data were taken from cross-sectional cohorts and from one timepoint from longitudinal studies (at least 3 months after onset in studies of optic neuritis). We classified data on eyes into healthy controls, multiple-sclerosis-associated optic neuritis (MSON), and multiple sclerosis without optic neuritis (MSNON). We assessed thickness of the retinal layers and we rated individual layer segmentation performance by random effects meta-analysis for MSON eyes versus control eyes, MSNON eyes versus control eyes, and MSNON eyes versus MSON eyes. We excluded relevant sources of bias by funnel plots. Of 25 497 records identified, 110 articles were eligible and 40 reported data (in total 5776 eyes from patients with multiple sclerosis [1667 MSON eyes and 4109 MSNON eyes] and 1697 eyes from healthy controls) that met published OCT quality control criteria and were suitable for meta-analysis. Compared with control eyes, the peripapillary retinal nerve fibre layer (RNFL) showed thinning in MSON eyes (mean difference -20·10 μm, 95% CI -22·76 to -17·44; pmultiple sclerosis and control eyes were found in the peripapillary RNFL and macular GCIPL. Inflammatory disease activity might be captured by the INL. Because of the consistency, robustness, and large effect size, we

  16. Interventional Effects for Mediation Analysis with Multiple Mediators.

    Science.gov (United States)

    Vansteelandt, Stijn; Daniel, Rhian M

    2017-03-01

    The mediation formula for the identification of natural (in)direct effects has facilitated mediation analyses that better respect the nature of the data, with greater consideration of the need for confounding control. The default assumptions on which it relies are strong, however. In particular, they are known to be violated when confounders of the mediator-outcome association are affected by the exposure. This complicates extensions of counterfactual-based mediation analysis to settings that involve repeatedly measured mediators, or multiple correlated mediators. VanderWeele, Vansteelandt, and Robins introduced so-called interventional (in)direct effects. These can be identified under much weaker conditions than natural (in)direct effects, but have the drawback of not adding up to the total effect. In this article, we adapt their proposal to achieve an exact decomposition of the total effect, and extend it to the multiple mediator setting. Interestingly, the proposed effects capture the path-specific effects of an exposure on an outcome that are mediated by distinct mediators, even when-as often-the structural dependence between the multiple mediators is unknown, for instance, when the direction of the causal effects between the mediators is unknown, or there may be unmeasured common causes of the mediators.

  17. Mediation analysis with multiple versions of the mediator.

    Science.gov (United States)

    Vanderweele, Tyler J

    2012-05-01

    The causal inference literature has provided definitions of direct and indirect effects based on counterfactuals that generalize the approach found in the social science literature. However, these definitions presuppose well-defined hypothetical interventions on the mediator. In many settings, there may be multiple ways to fix the mediator to a particular value, and these various hypothetical interventions may have very different implications for the outcome of interest. In this paper, we consider mediation analysis when multiple versions of the mediator are present. Specifically, we consider the problem of attempting to decompose a total effect of an exposure on an outcome into the portion through the intermediate and the portion through other pathways. We consider the setting in which there are multiple versions of the mediator but the investigator has access only to data on the particular measurement, not information on which version of the mediator may have brought that value about. We show that the quantity that is estimated as a natural indirect effect using only the available data does indeed have an interpretation as a particular type of mediated effect; however, the quantity estimated as a natural direct effect, in fact, captures both a true direct effect and an effect of the exposure on the outcome mediated through the effect of the version of the mediator that is not captured by the mediator measurement. The results are illustrated using 2 examples from the literature, one in which the versions of the mediator are unknown and another in which the mediator itself has been dichotomized.

  18. Visualization-based analysis of multiple response survey data

    Science.gov (United States)

    Timofeeva, Anastasiia

    2017-11-01

    During the survey, the respondents are often allowed to tick more than one answer option for a question. Analysis and visualization of such data have difficulties because of the need for processing multiple response variables. With standard representation such as pie and bar charts, information about the association between different answer options is lost. The author proposes a visualization approach for multiple response variables based on Venn diagrams. For a more informative representation with a large number of overlapping groups it is suggested to use similarity and association matrices. Some aggregate indicators of dissimilarity (similarity) are proposed based on the determinant of the similarity matrix and the maximum eigenvalue of association matrix. The application of the proposed approaches is well illustrated by the example of the analysis of advertising sources. Intersection of sets indicates that the same consumer audience is covered by several advertising sources. This information is very important for the allocation of the advertising budget. The differences between target groups in advertising sources are of interest. To identify such differences the hypothesis of homogeneity and independence are tested. Recent approach to the problem are briefly reviewed and compared. An alternative procedure is suggested. It is based on partition of a consumer audience into pairwise disjoint subsets and includes hypothesis testing of the difference between the population proportions. It turned out to be more suitable for the real problem being solved.

  19. Two-Way Regularized Fuzzy Clustering of Multiple Correspondence Analysis.

    Science.gov (United States)

    Kim, Sunmee; Choi, Ji Yeh; Hwang, Heungsun

    2017-01-01

    Multiple correspondence analysis (MCA) is a useful tool for investigating the interrelationships among dummy-coded categorical variables. MCA has been combined with clustering methods to examine whether there exist heterogeneous subclusters of a population, which exhibit cluster-level heterogeneity. These combined approaches aim to classify either observations only (one-way clustering of MCA) or both observations and variable categories (two-way clustering of MCA). The latter approach is favored because its solutions are easier to interpret by providing explicitly which subgroup of observations is associated with which subset of variable categories. Nonetheless, the two-way approach has been built on hard classification that assumes observations and/or variable categories to belong to only one cluster. To relax this assumption, we propose two-way fuzzy clustering of MCA. Specifically, we combine MCA with fuzzy k-means simultaneously to classify a subgroup of observations and a subset of variable categories into a common cluster, while allowing both observations and variable categories to belong partially to multiple clusters. Importantly, we adopt regularized fuzzy k-means, thereby enabling us to decide the degree of fuzziness in cluster memberships automatically. We evaluate the performance of the proposed approach through the analysis of simulated and real data, in comparison with existing two-way clustering approaches.

  20. Periodontal Disease and Incident Lung Cancer Risk: A Meta-Analysis of Cohort Studies.

    Science.gov (United States)

    Zeng, Xian-Tao; Xia, Ling-Yun; Zhang, Yong-Gang; Li, Sheng; Leng, Wei-Dong; Kwong, Joey S W

    2016-10-01

    Periodontal disease is linked to a number of systemic diseases such as cardiovascular diseases and diabetes mellitus. Recent evidence has suggested periodontal disease might be associated with lung cancer. However, their precise relationship is yet to be explored. Hence, this study aims to investigate the association of periodontal disease and risk of incident lung cancer using a meta-analytic approach. PubMed, Scopus, and ScienceDirect were searched up to June 10, 2015. Cohort and nested case-control studies investigating risk of lung cancer in patients with periodontal disease were included. Hazard ratios (HRs) were calculated, as were their 95% confidence intervals (CIs) using a fixed-effect inverse-variance model. Statistical heterogeneity was explored using the Q test as well as the I(2) statistic. Publication bias was assessed by visual inspection of funnel plots symmetry and Egger's test. Five cohort studies were included, involving 321,420 participants in this meta-analysis. Summary estimates based on adjusted data showed that periodontal disease was associated with a significant risk of lung cancer (HR = 1.24, 95% CI = 1.13 to 1.36; I(2) = 30%). No publication bias was detected. Subgroup analysis indicated that the association of periodontal disease and lung cancer remained significant in the female population. Evidence from cohort studies suggests that patients with periodontal disease are at increased risk of developing lung cancer.

  1. Comparing conVEntional RadioTherapy with stereotactIC body radiotherapy in patients with spinAL metastases: study protocol for an randomized controlled trial following the cohort multiple randomized controlled trial design

    International Nuclear Information System (INIS)

    Velden, Joanne M. van der; Verkooijen, Helena M.; Seravalli, Enrica; Hes, Jochem; Gerlich, A. Sophie; Kasperts, Nicolien; Eppinga, Wietse S. C.; Verlaan, Jorrit-Jan; Vulpen, Marco van

    2016-01-01

    Standard radiotherapy is the treatment of first choice in patients with symptomatic spinal metastases, but is only moderately effective. Stereotactic body radiation therapy is increasingly used to treat spinal metastases, without randomized evidence of superiority over standard radiotherapy. The VERTICAL study aims to quantify the effect of stereotactic radiation therapy in patients with metastatic spinal disease. This study follows the ‘cohort multiple Randomized Controlled Trial’ design. The VERTICAL study is conducted within the PRESENT cohort. In PRESENT, all patients with bone metastases referred for radiation therapy are enrolled. For each patient, clinical and patient-reported outcomes are captured at baseline and at regular intervals during follow-up. In addition, patients give informed consent to be offered experimental interventions. Within PRESENT, 110 patients are identified as a sub cohort of eligible patients (i.e. patients with unirradiated painful, mechanically stable spinal metastases who are able to undergo stereotactic radiation therapy). After a protocol amendment, also patients with non-spinal bony metastases are eligible. From the sub cohort, a random selection of patients is offered stereotactic radiation therapy (n = 55), which patients may accept or refuse. Only patients accepting stereotactic radiation therapy sign informed consent for the VERTICAL trial. Non-selected patients (n = 55) receive standard radiotherapy, and are not aware of them serving as controls. Primary endpoint is pain response after three months. Data will be analyzed by intention to treat, complemented by instrumental variable analysis in case of substantial refusal of the stereotactic radiation therapy in the intervention arm. This study is designed to quantify the treatment response after (stereotactic) radiation therapy in patients with symptomatic spinal metastases. This is the first randomized study in palliative care following the cohort multiple Randomized

  2. Age-period-cohort analysis of tuberculosis notifications in Hong Kong from 1961 to 2005.

    Science.gov (United States)

    Wu, P; Cowling, B J; Schooling, C M; Wong, I O L; Johnston, J M; Leung, C-C; Tam, C-M; Leung, G M

    2008-04-01

    Despite its wealth, excellent vital indices and robust health care infrastructure, Hong Kong has a relatively high incidence of tuberculosis (TB) (85.4 per 100 000). Hong Kong residents have also experienced a very rapid and recent epidemiological transition; the population largely originated from migration by southern Chinese in the mid 20th century. Given the potentially long latency period of TB infection, an investigation was undertaken to determine the extent to which TB incidence rates reflect the population history and the impact of public health interventions. An age-period-cohort model was used to break down the Hong Kong TB notification rates from 1961 to 2005 into the effects of age, calendar period and birth cohort. Analysis by age showed a consistent pattern across all the cohorts by year of birth, with a peak in the relative risk of TB at 20-24 years of age. Analysis by year of birth showed an increase in the relative risk of TB from 1880 to 1900, stable risk until 1910, then a linear rate of decline from 1910 with an inflection point at 1990 for a steeper rate of decline. Period effects yielded only one inflection during the calendar years 1971-5. Economic development, social change and the World Health Organisation's short-course directly observed therapy (DOTS) strategy have contributed to TB control in Hong Kong. The linear cohort effect until 1990 suggests that a relatively high, but slowly falling, incidence of TB in Hong Kong will continue into the next few decades.

  3. Association between metformin use and progression of monoclonal gammopathy of undetermined significance to multiple myeloma in US veterans with diabetes mellitus: a population-based retrospective cohort study.

    Science.gov (United States)

    Chang, Su-Hsin; Luo, Suhong; O'Brian, Katiuscia K; Thomas, Theodore S; Colditz, Graham A; Carlsson, Nils P; Carson, Kenneth R

    2015-01-01

    Multiple myeloma is one of the most common haematological malignancies in the USA and is consistently preceded by monoclonal gammopathy of undetermined significance (MGUS). We aimed to assess the association between metformin use and progression of MGUS to multiple myeloma. We did a retrospective cohort study of patients registered in the US Veterans Health Administration database and diagnosed with MGUS between Oct 1, 1999, and Dec 31, 2009. We included patients (aged >18 years) with at least one International Classification of Diseases (9th revision) code for diabetes mellitus and one treatment for their diabetes before MGUS diagnosis. We reviewed patient-level clinical data to verify diagnoses and extract any available data for size of baseline M-protein and type of MGUS. We defined metformin users as patients with diabetes who were given metformin consistently for 4 years after their diabetes diagnosis and before multiple myeloma development, death, or censorship. Our primary outcome was time from MGUS diagnosis to multiple myeloma diagnosis. We used Kaplan-Meier curves and Cox models to analyse the association between metformin use and MGUS progression. We obtained data for 3287 patients, of whom 2003 (61%) were included in the final analytical cohort. Median follow-up was 69 months (IQR 49–96). 463 (23%) participants were metformin users and 1540 (77%) participants were non-users. 13 (3%) metformin users progressed to multiple myeloma compared with 74 (5%) non-users. After adjustment, metformin use was associated with a reduced risk of progression to multiple myeloma (hazard ratio 0·47, 95% CI 0·25–0·87). For patients with diabetes diagnosed with MGUS, metformin use for 4 years or longer was associated with a reduced risk of progression of MGUS to multiple myeloma. Prospective studies are needed to establish whether this association is causal and whether these results can be extrapolated to non-diabetic individuals. Barnes-Jewish Hospital Foundation

  4. Cholecystectomy can increase the risk of colorectal cancer: A meta-analysis of 10 cohort studies.

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    Full Text Available This study aimed to elucidate the effects of cholecystectomy on the risk of colorectal cancer (CRC by conducting a meta-analysis of 10 cohort studies.The eligible cohort studies were selected by searching the PubMed and EMBASE databases from their origination to June 30, 2016, as well as by consulting the reference lists of the selected articles. Two authors individually collected the data from the 10 papers. When the data showed marked heterogeneity, we used a random-effects model to estimate the overall pooled risk; otherwise, a fixed effects model was employed.The final analysis included ten cohort studies. According to the Newcastle-Ottawa Scale (NOS, nine papers were considered high quality. After the data of these 9 studies were combined, an increased risk of CRC was found among the individuals who had undergone cholecystectomy (risk ratio (RR 1.22; 95% confidence interval (CI 1.08-1.38. In addition, we also found a promising increased risk for colon cancer (CC (RR 1.30, 95% CI 1.07-1.58, but no relationship between cholecystectomy and rectum cancer (RC (RR 1.09; 95% CI 0.89-1.34 was observed. Additionally, in the sub-group analysis of the tumor location in the colon, a positive risk for ascending colon cancer (ACC was found (RR 1.18, 95% CI 1.11-1.26. After combining the ACC, transverse colon cancer (TCC, sigmoid colon cancer (SCC and descending colon cancer (DCC patients, we found a positive relationship with cholecystectomy (RR 1.18, 95% CI 1.11-1.26. Furthermore, after combining the ACC and DCC patients, we also found a positive relationship with cholecystectomy (RR 1.28; 95% CI 1.11-1.26 in the sub-group analysis. In an additional sub-group analysis of patients from Western countries, there was a positive relationship between cholecystectomy and the risk of CRC (RR 1.20; 95% CI 1.05-1.36. Furthermore, a positive relationship between female gender and CRC was also found (RR 1.17; 95% CI 1.03-1.34. However, there was no relationship

  5. Influence of exposure assessment and parameterization on exposure response. Aspects of epidemiologic cohort analysis using the Libby Amphibole asbestos worker cohort.

    Science.gov (United States)

    Bateson, Thomas F; Kopylev, Leonid

    2015-01-01

    Recent meta-analyses of occupational epidemiology studies identified two important exposure data quality factors in predicting summary effect measures for asbestos-associated lung cancer mortality risk: sufficiency of job history data and percent coverage of work history by measured exposures. The objective was to evaluate different exposure parameterizations suggested in the asbestos literature using the Libby, MT asbestos worker cohort and to evaluate influences of exposure measurement error caused by historically estimated exposure data on lung cancer risks. Focusing on workers hired after 1959, when job histories were well-known and occupational exposures were predominantly based on measured exposures (85% coverage), we found that cumulative exposure alone, and with allowance of exponential decay, fit lung cancer mortality data similarly. Residence-time-weighted metrics did not fit well. Compared with previous analyses based on the whole cohort of Libby workers hired after 1935, when job histories were less well-known and exposures less frequently measured (47% coverage), our analyses based on higher quality exposure data yielded an effect size as much as 3.6 times higher. Future occupational cohort studies should continue to refine retrospective exposure assessment methods, consider multiple exposure metrics, and explore new methods of maintaining statistical power while minimizing exposure measurement error.

  6. Multiple Sclerosis Increases Fracture Risk: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Guixian Dong

    2015-01-01

    Full Text Available Purpose. The association between multiple sclerosis (MS and fracture risk has been reported, but results of previous studies remain controversial and ambiguous. To assess the association between MS and fracture risk, a meta-analysis was performed. Method. Based on comprehensive searches of the PubMed, Embase, and Web of Science, we identified outcome data from all articles estimating the association between MS and fracture risk. The pooled risk ratios (RRs with 95% confidence intervals (CIs were calculated. Results. A significant association between MS and fracture risk was found. This result remained statistically significant when the adjusted RRs were combined. Subgroup analysis stratified by the site of fracture suggested significant associations between MS and tibia fracture risk, femur fracture risk, hip fracture risk, pelvis fracture risk, vertebrae fracture risk, and humerus fracture risk. In the subgroup analysis by gender, female MS patients had increased fracture risk. When stratified by history of drug use, use of antidepressants, hypnotics/anxiolytics, anticonvulsants, and glucocorticoids increased the risk of fracture risk in MS patients. Conclusions. This meta-analysis demonstrated that MS was significantly associated with fracture risk.

  7. Weibull and lognormal Taguchi analysis using multiple linear regression

    International Nuclear Information System (INIS)

    Piña-Monarrez, Manuel R.; Ortiz-Yañez, Jesús F.

    2015-01-01

    The paper provides to reliability practitioners with a method (1) to estimate the robust Weibull family when the Taguchi method (TM) is applied, (2) to estimate the normal operational Weibull family in an accelerated life testing (ALT) analysis to give confidence to the extrapolation and (3) to perform the ANOVA analysis to both the robust and the normal operational Weibull family. On the other hand, because the Weibull distribution neither has the normal additive property nor has a direct relationship with the normal parameters (µ, σ), in this paper, the issues of estimating a Weibull family by using a design of experiment (DOE) are first addressed by using an L_9 (3"4) orthogonal array (OA) in both the TM and in the Weibull proportional hazard model approach (WPHM). Then, by using the Weibull/Gumbel and the lognormal/normal relationships and multiple linear regression, the direct relationships between the Weibull and the lifetime parameters are derived and used to formulate the proposed method. Moreover, since the derived direct relationships always hold, the method is generalized to the lognormal and ALT analysis. Finally, the method’s efficiency is shown through its application to the used OA and to a set of ALT data. - Highlights: • It gives the statistical relations and steps to use the Taguchi Method (TM) to analyze Weibull data. • It gives the steps to determine the unknown Weibull family to both the robust TM setting and the normal ALT level. • It gives a method to determine the expected lifetimes and to perform its ANOVA analysis in TM and ALT analysis. • It gives a method to give confidence to the extrapolation in an ALT analysis by using the Weibull family of the normal level.

  8. Sensitivity analysis in multiple imputation in effectiveness studies of psychotherapy.

    Science.gov (United States)

    Crameri, Aureliano; von Wyl, Agnes; Koemeda, Margit; Schulthess, Peter; Tschuschke, Volker

    2015-01-01

    The importance of preventing and treating incomplete data in effectiveness studies is nowadays emphasized. However, most of the publications focus on randomized clinical trials (RCT). One flexible technique for statistical inference with missing data is multiple imputation (MI). Since methods such as MI rely on the assumption of missing data being at random (MAR), a sensitivity analysis for testing the robustness against departures from this assumption is required. In this paper we present a sensitivity analysis technique based on posterior predictive checking, which takes into consideration the concept of clinical significance used in the evaluation of intra-individual changes. We demonstrate the possibilities this technique can offer with the example of irregular longitudinal data collected with the Outcome Questionnaire-45 (OQ-45) and the Helping Alliance Questionnaire (HAQ) in a sample of 260 outpatients. The sensitivity analysis can be used to (1) quantify the degree of bias introduced by missing not at random data (MNAR) in a worst reasonable case scenario, (2) compare the performance of different analysis methods for dealing with missing data, or (3) detect the influence of possible violations to the model assumptions (e.g., lack of normality). Moreover, our analysis showed that ratings from the patient's and therapist's version of the HAQ could significantly improve the predictive value of the routine outcome monitoring based on the OQ-45. Since analysis dropouts always occur, repeated measurements with the OQ-45 and the HAQ analyzed with MI are useful to improve the accuracy of outcome estimates in quality assurance assessments and non-randomized effectiveness studies in the field of outpatient psychotherapy.

  9. Pessary placement in the prevention of preterm birth in multiple pregnancies: a propensity score analysis

    NARCIS (Netherlands)

    Monfrance, Maurice J. M.; Schuit, Ewoud; Groenwold, Rolf H.; Oudijk, Martijn A.; de Graaf, Irene M.; Bax, Caroline J.; Bekedam, Dick J.; Mol, Ben Willem; Langenveld, Josje

    2016-01-01

    In asymptomatic women with a multiple pregnancy and short cervix prophylactic use of a cervical pessary might reduce preterm birth. We assessed the possible treatment effects of pessary use in pregnancy duration and for poor perinatal outcome. This cohort study was performed between December 2012

  10. Pessary placement in the prevention of preterm birth in multiple pregnancies : a propensity score analysis

    NARCIS (Netherlands)

    Monfrance, Maurice J M; Schuit, Ewoud; Groenwold, Rolf H; Oudijk, Martijn A; de Graaf, Irene M; Bax, Caroline J; Bekedam, Dick J; Mol, Ben Willem; Langenveld, Josje

    OBJECTIVE: In asymptomatic women with a multiple pregnancy and short cervix prophylactic use of a cervical pessary might reduce preterm birth. We assessed the possible treatment effects of pessary use in pregnancy duration and for poor perinatal outcome. STUDY DESIGN: This cohort study was performed

  11. Sensitivity analysis for the effects of multiple unmeasured confounders.

    Science.gov (United States)

    Groenwold, Rolf H H; Sterne, Jonathan A C; Lawlor, Debbie A; Moons, Karel G M; Hoes, Arno W; Tilling, Kate

    2016-09-01

    Observational studies are prone to (unmeasured) confounding. Sensitivity analysis of unmeasured confounding typically focuses on a single unmeasured confounder. The purpose of this study was to assess the impact of multiple (possibly weak) unmeasured confounders. Simulation studies were performed based on parameters estimated from the British Women's Heart and Health Study, including 28 measured confounders and assuming no effect of ascorbic acid intake on mortality. In addition, 25, 50, or 100 unmeasured confounders were simulated, with various mutual correlations and correlations with measured confounders. The correlated unmeasured confounders did not need to be strongly associated with exposure and outcome to substantially bias the exposure-outcome association at interest, provided that there are sufficiently many unmeasured confounders. Correlations between unmeasured confounders, in addition to the strength of their relationship with exposure and outcome, are key drivers of the magnitude of unmeasured confounding and should be considered in sensitivity analyses. However, if the unmeasured confounders are correlated with measured confounders, the bias yielded by unmeasured confounders is partly removed through adjustment for the measured confounders. Discussions of the potential impact of unmeasured confounding in observational studies, and sensitivity analyses to examine this, should focus on the potential for the joint effect of multiple unmeasured confounders to bias results. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Preoperative widespread pain sensitization and chronic pain after hip and knee replacement: a cohort analysis

    Science.gov (United States)

    Wylde, Vikki; Sayers, Adrian; Lenguerrand, Erik; Gooberman-Hill, Rachael; Pyke, Mark; Beswick, Andrew D.; Dieppe, Paul; Blom, Ashley W.

    2015-01-01

    Abstract Chronic pain after joint replacement is common, affecting approximately 10% of patients after total hip replacement (THR) and 20% of patients after total knee replacement (TKR). Heightened generalized sensitivity to nociceptive input could be a risk factor for the development of this pain. The primary aim of this study was to investigate whether preoperative widespread pain sensitivity was associated with chronic pain after joint replacement. Data were analyzed from 254 patients receiving THR and 239 patients receiving TKR. Pain was assessed preoperatively and at 12 months after surgery using the Western Ontario and McMaster Universities Osteoarthritis Pain Scale. Preoperative widespread pain sensitivity was assessed through measurement of pressure pain thresholds (PPTs) at the forearm using an algometer. Statistical analysis was conducted using linear regression and linear mixed models, and adjustments were made for confounding variables. In both the THR and TKR cohort, lower PPTs (heightened widespread pain sensitivity) were significantly associated with higher preoperative pain severity. Lower PPTs were also significantly associated with higher pain severity at 12 months after surgery in the THR cohort. However, PPTs were not associated with the change in pain severity from preoperative to 12 months postoperative in either the TKR or THR cohort. These findings suggest that although preoperative widespread pressure pain sensitivity is associated with pain severity before and after joint replacement, it is not a predictor of the amount of pain relief that patients gain from joint replacement surgery, independent of preoperative pain severity. PMID:25599300

  13. Physical self-concept changes in a selective sport high school: a longitudinal cohort-sequence analysis of the big-fish-little-pond effect.

    Science.gov (United States)

    Marsh, Herbert W; Morin, Alexandre J; Parker, Philip D

    2015-04-01

    Elite athletes and nonathletes (N = 1,268) attending the same selective sport high school (4 high school age cohorts, grades 7-10, mean ages varying from 10.9 to 14.1) completed the same physical self-concept instrument 4 times over a 2-year period (multiple waves). We introduce a latent cohort-sequence analysis that provides a stronger basis for assessing developmental stability/change than either cross-sectional (multicohort, single occasion) or longitudinal (single-cohort, multiple occasion) designs, allowing us to evaluate latent means across 10 waves spanning a 5-year period (grades 7-11), although each participant contributed data for only 4 waves, spanning 2 of the 5 years. Consistent with the frame-of-reference effects embodied in the big-fish-little-pond effect (BFLPE), physical self-concepts at the start of high school were much higher for elite athletes than for nonathlete classmates, but the differences declined over time so that by the end of high school there were no differences in the 2 groups. Gender differences in favor of males had a negative linear and quadratic trajectory over time, but the consistently smaller gender differences for athletes than for nonathletes did not vary with time.

  14. Passive smoking and risk of type 2 diabetes: a meta-analysis of prospective cohort studies.

    Directory of Open Access Journals (Sweden)

    Ying Wang

    Full Text Available BACKGROUNDS/OBJECTIVE: The prevalence of diabetes is increasing rapidly all over the world. However, studies on passive smoking and type 2 diabetes have not been systematically assessed. Therefore, we conducted a meta-analysis to explore whether an association exists between passive smoking and risk of type 2 diabetes. METHODS: We searched PubMed, EMBASE, Cochrane library and Web of Science up to April 9(th, 2013, to identify prospective cohort studies that assessed passive smoking and risk of type 2 diabetes. The fixed-effect model was used to calculate the overall relative risk (RR. RESULT: 4 prospective cohort studies were included for analysis, with a total of 112,351 participants involved. The pooled RR was 1.28 (95% confidence interval (CI 1.14 to 1.44 comparing those who were exposed to passive smoking with those who were not. Subgroup, sensitivity analysis and publication bias test suggested the overall result of this analysis was robust. CONCLUSIONS: Passive smoking is associated with a significantly increased risk of type 2 diabetes. Further well-designed studies are warranted to confirm this association.

  15. Multiple Score Comparison: a network meta-analysis approach to comparison and external validation of prognostic scores

    Directory of Open Access Journals (Sweden)

    Sarah R. Haile

    2017-12-01

    Full Text Available Abstract Background Prediction models and prognostic scores have been increasingly popular in both clinical practice and clinical research settings, for example to aid in risk-based decision making or control for confounding. In many medical fields, a large number of prognostic scores are available, but practitioners may find it difficult to choose between them due to lack of external validation as well as lack of comparisons between them. Methods Borrowing methodology from network meta-analysis, we describe an approach to Multiple Score Comparison meta-analysis (MSC which permits concurrent external validation and comparisons of prognostic scores using individual patient data (IPD arising from a large-scale international collaboration. We describe the challenges in adapting network meta-analysis to the MSC setting, for instance the need to explicitly include correlations between the scores on a cohort level, and how to deal with many multi-score studies. We propose first using IPD to make cohort-level aggregate discrimination or calibration scores, comparing all to a common comparator. Then, standard network meta-analysis techniques can be applied, taking care to consider correlation structures in cohorts with multiple scores. Transitivity, consistency and heterogeneity are also examined. Results We provide a clinical application, comparing prognostic scores for 3-year mortality in patients with chronic obstructive pulmonary disease using data from a large-scale collaborative initiative. We focus on the discriminative properties of the prognostic scores. Our results show clear differences in performance, with ADO and eBODE showing higher discrimination with respect to mortality than other considered scores. The assumptions of transitivity and local and global consistency were not violated. Heterogeneity was small. Conclusions We applied a network meta-analytic methodology to externally validate and concurrently compare the prognostic properties

  16. Laplace transform analysis of a multiplicative asset transfer model

    Science.gov (United States)

    Sokolov, Andrey; Melatos, Andrew; Kieu, Tien

    2010-07-01

    We analyze a simple asset transfer model in which the transfer amount is a fixed fraction f of the giver’s wealth. The model is analyzed in a new way by Laplace transforming the master equation, solving it analytically and numerically for the steady-state distribution, and exploring the solutions for various values of f∈(0,1). The Laplace transform analysis is superior to agent-based simulations as it does not depend on the number of agents, enabling us to study entropy and inequality in regimes that are costly to address with simulations. We demonstrate that Boltzmann entropy is not a suitable (e.g. non-monotonic) measure of disorder in a multiplicative asset transfer system and suggest an asymmetric stochastic process that is equivalent to the asset transfer model.

  17. CHOOSING A HEALTH INSTITUTION WITH MULTIPLE CORRESPONDENCE ANALYSIS AND CLUSTER ANALYSIS IN A POPULATION BASED STUDY

    Directory of Open Access Journals (Sweden)

    ASLI SUNER

    2013-06-01

    Full Text Available Multiple correspondence analysis is a method making easy to interpret the categorical variables given in contingency tables, showing the similarities, associations as well as divergences among these variables via graphics on a lower dimensional space. Clustering methods are helped to classify the grouped data according to their similarities and to get useful summarized data from them. In this study, interpretations of multiple correspondence analysis are supported by cluster analysis; factors affecting referred health institute such as age, disease group and health insurance are examined and it is aimed to compare results of the methods.

  18. Person mobility in the design and analysis of cluster-randomized cohort prevention trials.

    Science.gov (United States)

    Vuchinich, Sam; Flay, Brian R; Aber, Lawrence; Bickman, Leonard

    2012-06-01

    Person mobility is an inescapable fact of life for most cluster-randomized (e.g., schools, hospitals, clinic, cities, state) cohort prevention trials. Mobility rates are an important substantive consideration in estimating the effects of an intervention. In cluster-randomized trials, mobility rates are often correlated with ethnicity, poverty and other variables associated with disparity. This raises the possibility that estimated intervention effects may generalize to only the least mobile segments of a population and, thus, create a threat to external validity. Such mobility can also create threats to the internal validity of conclusions from randomized trials. Researchers must decide how to deal with persons who leave study clusters during a trial (dropouts), persons and clusters that do not comply with an assigned intervention, and persons who enter clusters during a trial (late entrants), in addition to the persons who remain for the duration of a trial (stayers). Statistical techniques alone cannot solve the key issues of internal and external validity raised by the phenomenon of person mobility. This commentary presents a systematic, Campbellian-type analysis of person mobility in cluster-randomized cohort prevention trials. It describes four approaches for dealing with dropouts, late entrants and stayers with respect to data collection, analysis and generalizability. The questions at issue are: 1) From whom should data be collected at each wave of data collection? 2) Which cases should be included in the analyses of an intervention effect? and 3) To what populations can trial results be generalized? The conclusions lead to recommendations for the design and analysis of future cluster-randomized cohort prevention trials.

  19. Serum Lipids and Breast Cancer Risk: A Meta-Analysis of Prospective Cohort Studies.

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    Haibo Ni

    Full Text Available Epidemiologic studies exploring causal associations between serum lipids and breast cancer risk have reported contradictory results. We conducted a meta-analysis of prospective cohort studies to evaluate these associations.Relevant studies were identified by searching PubMed and EMBASE through April 2015. We included prospective cohort studies that reported relative risk (RR estimates with 95% confidence intervals (CIs for the associations of specific lipid components (i.e., total cholesterol [TC], high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C], and triglycerides [TG] with breast cancer risk. Either a fixed- or a random-effects model was used to calculate pooled RRs.Fifteen prospective cohort studies involving 1,189,635 participants and 23,369 breast cancer cases were included in the meta-analysis. The pooled RRs of breast cancer for the highest versus lowest categories were 0.96 (95% CI: 0.86-1.07 for TC, 0.92 (95% CI: 0.73-1.16 for HDL-C, 0.90 (95% CI: 0.77-1.06 for LDL-C, and 0.93 (95% CI: 0.86-1.00 for TG. Notably, for HDL-C, a significant reduction of breast cancer risk was observed among postmenopausal women (RR = 0.77, 95% CI: 0.64-0.93 but not among premenopausal women. Similar trends of the associations were observed in the dose-response analysis.Our findings suggest that serum levels of TG but not TC and LDL-C may be inversely associated with breast cancer risk. Serum HDL-C may also protect against breast carcinogenesis among postmenopausal women.

  20. A mathematical analysis of multiple-target SELEX.

    Science.gov (United States)

    Seo, Yeon-Jung; Chen, Shiliang; Nilsen-Hamilton, Marit; Levine, Howard A

    2010-10-01

    SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is a procedure by which a mixture of nucleic acids can be fractionated with the goal of identifying those with specific biochemical activities. One combines the mixture with a specific target molecule and then separates the target-NA complex from the resulting reactions. The target-NA complex is separated from the unbound NA by mechanical means (such as by filtration), the NA is eluted from the complex, amplified by PCR (polymerase chain reaction), and the process repeated. After several rounds, one should be left with the nucleic acids that best bind to the target. The problem was first formulated mathematically in Irvine et al. (J. Mol. Biol. 222:739-761, 1991). In Levine and Nilsen-Hamilton (Comput. Biol. Chem. 31:11-25, 2007), a mathematical analysis of the process was given. In Vant-Hull et al. (J. Mol. Biol. 278:579-597, 1998), multiple target SELEX was considered. It was assumed that each target has a single nucleic acid binding site that permits occupation by no more than one nucleic acid. Here, we revisit Vant-Hull et al. (J. Mol. Biol. 278:579-597, 1998) using the same assumptions. The iteration scheme is shown to be convergent and a simplified algorithm is given. Our interest here is in the behavior of the multiple target SELEX process as a discrete "time" dynamical system. Our goal is to characterize the limiting states and their dependence on the initial distribution of nucleic acid and target fraction components. (In multiple target SELEX, we vary the target component fractions, but not their concentrations, as fixed and the initial pool of nucleic acids as a variable starting condition). Given N nucleic acids and a target consisting of M subtarget component species, there is an M × N matrix of affinities, the (i,j) entry corresponding to the affinity of the jth nucleic acid for the ith subtarget. We give a structure condition on this matrix that is equivalent to the following

  1. Early onset hyperuricemia is a prognostic marker for kidney graft failure: Propensity score matching analysis in a Korean multicenter cohort.

    Directory of Open Access Journals (Sweden)

    Miyeun Han

    Full Text Available It remains inconclusive whether hyperuricemia is a true risk factor for kidney graft failure. In the current study, we investigated the association of hyperuricemia and graft outcome. We performed a multi-center cohort study that included 2620 kidney transplant recipients. The patients were classified as either normouricemic or hyperuricemic at 3 months after transplantation. Hyperuricemia was defined as a serum uric acid level ≥ 7.0 mg/dL in males or ≥ 6.0 mg/dL in females or based on the use of urate-lowering medications. The two groups were compared before and after propensity score matching. A total of 657 (25.1% patients were classified as hyperuricemic. The proportion of hyperuricemic patients increased over time, reaching 44.2% of the total cohort at 5 years after transplantation. Estimated glomerular filtration rate and donor type were independently associated with hyperuricemia. Hyperuricemia was associated with graft loss according to multiple Cox regression analysis before propensity score matching (hazard ratio [HR] = 1.56, 95% confidence interval [CI] = 1.14-2.13, P = 0.005 as well as after matching (HR = 1.65, 95% CI = 1.13-2.42, p = 0.010. Cox regression models using time-varying hyperuricemia or marginal structural models adjusted with time-varying eGFR also demonstrated significant hazards of hyperuricemia for graft loss. Cardiovascular events and recipient survival were not associated with hyperuricemia. Overall, hyperuricemia, especially early onset after transplantation, showed an increased risk for graft failure. Further studies are warranted to determine whether lowering serum uric acid levels would be beneficial to graft survival.

  2. Multidimensional severity assessment in bronchiectasis: an analysis of seven European cohorts.

    Science.gov (United States)

    McDonnell, M J; Aliberti, S; Goeminne, P C; Dimakou, K; Zucchetti, S C; Davidson, J; Ward, C; Laffey, J G; Finch, S; Pesci, A; Dupont, L J; Fardon, T C; Skrbic, D; Obradovic, D; Cowman, S; Loebinger, M R; Rutherford, R M; De Soyza, A; Chalmers, J D

    2016-12-01

    Bronchiectasis is a multidimensional disease associated with substantial morbidity and mortality. Two disease-specific clinical prediction tools have been developed, the Bronchiectasis Severity Index (BSI) and the FACED score, both of which stratify patients into severity risk categories to predict the probability of mortality. We aimed to compare the predictive utility of BSI and FACED in assessing clinically relevant disease outcomes across seven European cohorts independent of their original validation studies. The combined cohorts totalled 1612. Pooled analysis showed that both scores had a good discriminatory predictive value for mortality (pooled area under the curve (AUC) 0.76, 95% CI 0.74 to 0.78 for both scores) with the BSI demonstrating a higher sensitivity (65% vs 28%) but lower specificity (70% vs 93%) compared with the FACED score. Calibration analysis suggested that the BSI performed consistently well across all cohorts, while FACED consistently overestimated mortality in 'severe' patients (pooled OR 0.33 (0.23 to 0.48), p<0.0001). The BSI accurately predicted hospitalisations (pooled AUC 0.82, 95% CI 0.78 to 0.84), exacerbations, quality of life (QoL) and respiratory symptoms across all risk categories. FACED had poor discrimination for hospital admissions (pooled AUC 0.65, 95% CI 0.63 to 0.67) with low sensitivity at 16% and did not consistently predict future risk of exacerbations, QoL or respiratory symptoms. No association was observed with FACED and 6 min walk distance (6MWD) or lung function decline. The BSI accurately predicts mortality, hospital admissions, exacerbations, QoL, respiratory symptoms, 6MWD and lung function decline in bronchiectasis, providing a clinically relevant evaluation of disease severity. 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/.

  3. Age, period, and cohort analysis of regular dental care behavior and edentulism: A marginal approach

    Science.gov (United States)

    2011-01-01

    Background To analyze the regular dental care behavior and prevalence of edentulism in adult Danes, reported in sequential cross-sectional oral health surveys by the application of a marginal approach to consider the possible clustering effect of birth cohorts. Methods Data from four sequential cross-sectional surveys of non-institutionalized Danes conducted from 1975-2005 comprising 4330 respondents aged 15+ years in 9 birth cohorts were analyzed. The key study variables were seeking dental care on an annual basis (ADC) and edentulism. For the analysis of ADC, survey year, age, gender, socio-economic status (SES) group, denture-wearing, and school dental care (SDC) during childhood were considered. For the analysis of edentulism, only respondents aged 35+ years were included. Survey year, age, gender, SES group, ADC, and SDC during childhood were considered as the independent factors. To take into account the clustering effect of birth cohorts, marginal logistic regressions with an independent correlation structure in generalized estimating equations (GEE) were carried out, with PROC GENMOD in SAS software. Results The overall proportion of people seeking ADC increased from 58.8% in 1975 to 86.7% in 2005, while for respondents aged 35 years or older, the overall prevalence of edentulism (35+ years) decreased from 36.4% in 1975 to 5.0% in 2005. Females, respondents in the higher SES group, in more recent survey years, with no denture, and receiving SDC in all grades during childhood were associated with higher probability of seeking ADC regularly (P dental health policy was demonstrated by a continued increase of regular dental visiting habits and tooth retention in adults because school dental care was provided to Danes in their childhood. PMID:21410991

  4. Poisson regression analysis of the mortality among a cohort of World War II nuclear industry workers

    International Nuclear Information System (INIS)

    Frome, E.L.; Cragle, D.L.; McLain, R.W.

    1990-01-01

    A historical cohort mortality study was conducted among 28,008 white male employees who had worked for at least 1 month in Oak Ridge, Tennessee, during World War II. The workers were employed at two plants that were producing enriched uranium and a research and development laboratory. Vital status was ascertained through 1980 for 98.1% of the cohort members and death certificates were obtained for 96.8% of the 11,671 decedents. A modified version of the traditional standardized mortality ratio (SMR) analysis was used to compare the cause-specific mortality experience of the World War II workers with the U.S. white male population. An SMR and a trend statistic were computed for each cause-of-death category for the 30-year interval from 1950 to 1980. The SMR for all causes was 1.11, and there was a significant upward trend of 0.74% per year. The excess mortality was primarily due to lung cancer and diseases of the respiratory system. Poisson regression methods were used to evaluate the influence of duration of employment, facility of employment, socioeconomic status, birth year, period of follow-up, and radiation exposure on cause-specific mortality. Maximum likelihood estimates of the parameters in a main-effects model were obtained to describe the joint effects of these six factors on cause-specific mortality of the World War II workers. We show that these multivariate regression techniques provide a useful extension of conventional SMR analysis and illustrate their effective use in a large occupational cohort study

  5. Leukemia, lymphoma and multiple myeloma mortality (1950–1999) and incidence (1969–1999) in the Eldorado uranium workers cohort

    Energy Technology Data Exchange (ETDEWEB)

    Zablotska, Lydia B., E-mail: Lydia.Zablotska@ucsf.edu [Department of Epidemiology and Biostatistics, School of Medicine, University of California, San Francisco, CA 94118 (United States); Lane, Rachel S.D. [Radiation and Health Sciences Division, Directorate of Environmental and Radiation Protection and Assessment, Canadian Nuclear Safety Commission, Ottawa, ON, Canada K1P 5S9 (Canada); Frost, Stanley E. [Frost and Frost Consultants, Saskatoon, SK, Canada S7H 0A1 (Canada); Thompson, Patsy A. [Radiation and Health Sciences Division, Directorate of Environmental and Radiation Protection and Assessment, Canadian Nuclear Safety Commission, Ottawa, ON, Canada K1P 5S9 (Canada)

    2014-04-01

    Uranium workers are chronically exposed to low levels of radon decay products (RDP) and gamma (γ) radiation. Risks of leukemia from acute and high doses of γ-radiation are well-characterized, but risks from lower doses and dose-rates and from RDP exposures are controversial. Few studies have evaluated risks of other hematologic cancers in uranium workers. The purpose of this study was to analyze radiation-related risks of hematologic cancers in the cohort of Eldorado uranium miners and processors first employed in 1932–1980 in relation to cumulative RDP exposures and γ-ray doses. The average cumulative RDP exposure was 100.2 working level months and the average cumulative whole-body γ-radiation dose was 52.2 millisievert. We identified 101 deaths and 160 cases of hematologic cancers in the cohort. Overall, male workers had lower mortality and cancer incidence rates for all outcomes compared with the general Canadian male population, a likely healthy worker effect. No statistically significant association between RDP exposure or γ-ray doses, or a combination of both, and mortality or incidence of any hematologic cancer was found. We observed consistent but non-statistically significant increases in risks of chronic lymphocytic leukemia (CLL) and Hodgkin lymphoma (HL) incidence and non-Hodgkin lymphoma (NHL) mortality with increasing γ-ray doses. These findings are consistent with recent studies of increased risks of CLL and NHL incidence after γ-radiation exposure. Further research is necessary to understand risks of other hematologic cancers from low-dose exposures to γ-radiation. - Highlights: • We analyzed long-term follow-up for hematologic cancers of the Eldorado uranium workers. • Workers were exposed to a unique combination of radon decay products (RDP) and gamma (γ) ray doses. • Exposures to RDP and γ-ray doses were not associated with significantly increased risks of cancers. • Radiation risks of chronic lymphocytic leukemia (CLL) and

  6. Trace element analysis of environmental samples by multiple prompt gamma-ray analysis method

    International Nuclear Information System (INIS)

    Oshima, Masumi; Matsuo, Motoyuki; Shozugawa, Katsumi

    2011-01-01

    The multiple γ-ray detection method has been proved to be a high-resolution and high-sensitivity method in application to nuclide quantification. The neutron prompt γ-ray analysis method is successfully extended by combining it with the γ-ray detection method, which is called Multiple prompt γ-ray analysis, MPGA. In this review we show the principle of this method and its characteristics. Several examples of its application to environmental samples, especially river sediments in the urban area and sea sediment samples are also described. (author)

  7. The Swiss Multiple Sclerosis Cohort-Study (SMSC: A Prospective Swiss Wide Investigation of Key Phases in Disease Evolution and New Treatment Options.

    Directory of Open Access Journals (Sweden)

    Giulio Disanto

    Full Text Available The mechanisms leading to disability and the long-term efficacy and safety of disease modifying drugs (DMDs in multiple sclerosis (MS are unclear. We aimed at building a prospective cohort of MS patients with standardized collection of demographic, clinical, MRI data and body fluids that can be used to develop prognostic indicators and biomarkers of disease evolution and therapeutic response. The Swiss MS Cohort (SMSC is a prospective observational study performed across seven Swiss MS centers including patients with MS, clinically isolated syndrome (CIS, radiologically isolated syndrome or neuromyelitis optica. Neurological and radiological assessments and biological samples are collected every 6-12 months. We recruited 872 patients (clinically isolated syndrome [CIS] 5.5%, relapsing-remitting MS [RRMS] 85.8%, primary progressive MS [PPMS] 3.5%, secondary progressive MS [SPMS] 5.2% between June 2012 and July 2015. We performed 2,286 visits (median follow-up 398 days and collected 2,274 serum, plasma and blood samples, 152 cerebrospinal fluid samples and 1,276 brain MRI scans. 158 relapses occurred and expanded disability status scale (EDSS scores increased in PPMS, SPMS and RRMS patients experiencing relapses. Most RRMS patients were treated with fingolimod (33.4%, natalizumab (24.5% or injectable DMDs (13.6%. The SMSC will provide relevant information regarding DMDs efficacy and safety and will serve as a comprehensive infrastructure available for nested research projects.

  8. Benefit-risk perception of natalizumab therapy in neurologists and a large cohort of multiple sclerosis patients.

    Science.gov (United States)

    Heesen, Christoph; Kleiter, Ingo; Meuth, Sven G; Krämer, Julia; Kasper, Jürgen; Köpke, Sascha; Gaissmaier, Wolfgang

    2017-05-15

    Natalizumab (NAT) is associated with the risk of progressive multifocal leukoencephalopathy (PML). Risk stratification algorithms have been developed, however, without detectable reduction of PML incidence. To evaluate to which extent patients and physicians understand and accept risks associated with NAT treatment. Prospective observational cohort study in German MS centers (n=73) among NAT-treated MS patients (n=801) and their neurologists (n=99). Patients included in this study had mean disease duration of 10.2years and a mean NAT treatment duration of 24months. More than 90% of patients and physicians voted for shared decision making or an informed choice decision making approach. Patients and physicians perceived a similar threat from MS as serious disease and both overestimated treatment benefits from NAT based on trial data. Men perceived MS more severe than women and perception of seriousness increased with age in both groups and in patients as well with increasing disability. Although patients evaluated their PML risk higher, their risk acceptance was significantly higher than of their neurologists. Risk stratification knowledge was good among neurologists and significantly lower among patients. While patients and physicians seem to have realistic risk perception of PML and knowledge of risk stratification concepts, the threat of MS and the perception of treatment benefits may explain the ongoing high acceptance of PML risk. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Relationship between prostate-specific antigen and obesity in prostate cancer screening: analysis of a large cohort in Japan.

    Science.gov (United States)

    Kubota, Yasuaki; Seike, Kensaku; Maeda, Shinichi; Shinohara, Yuka; Iwata, Masamitsu; Sugimoto, Norio

    2011-01-01

    Previous studies have shown that lower prostate-specific antigen (PSA) levels in obese men might decrease the sensitivity of prostate cancer screening, leading to delayed diagnosis and unfavorable prognosis. We examined whether the effect of obesity is important in prostate cancer screening of Japanese men, who have a low prevalence of obesity. We analyzed 19,294 male subjects from a large cohort of Toyota Motor Corporation (TMC) employees (aged > 50 years, serum PSA level ≤ 4.0 ng/mL) who underwent physical examinations from August 2006 to December 2009. The relationship between PSA level and obesity-related factors was analyzed by simple and multiple regression analysis. The relationships between six body mass index (BMI) categories, and PSA level and PSA mass (PSA concentration × plasma volume) were analyzed. PSA level decreased significantly with increasing BMI, but the coefficient of determination was very low. Mean PSA values decreased from 1.02 to 0.85 ng/mL as BMI increased from underweight (BMI 35). However, PSA mass peaked in the overweight category and was slightly reduced with increasing BMI. On multiple regression analysis, PSA level was influenced by age, diastolic blood pressure and high-density lipoprotein as well as BMI. We found an inverse but weak relationship between PSA level and BMI. Obesity seems to have very limited influence on prostate cancer screening in this population. Nonetheless, when considering indications for prostatic biopsy in obese men, we should be aware that the hemodilution effect might reduce PSA levels. © 2010 The Japanese Urological Association.

  10. Analysis of 1:1 Matched Cohort Studies and Twin Studies, with Binary Exposures and Binary Outcomes

    OpenAIRE

    Sjölander, Arvid; Johansson, Anna L. V.; Lundholm, Cecilia; Altman, Daniel; Almqvist, Catarina; Pawitan, Yudi

    2012-01-01

    To improve confounder adjustments, observational studies are often matched on potential confounders. While matched case-control studies are common and well covered in the literature, our focus here is on matched cohort studies, which are less common and sparsely discussed in the literature. Matched data also arise naturally in twin studies, as a cohort of exposure–discordant twins can be viewed as being matched on a large number of potential confounders. The analysis of twin studies will be g...

  11. Using multiple decrement models to estimate risk and morbidity from specific AIDS illnesses. Multicenter AIDS Cohort Study (MACS).

    Science.gov (United States)

    Hoover, D R; Peng, Y; Saah, A J; Detels, R R; Day, R S; Phair, J P

    A simple non-parametric approach is developed to simultaneously estimate net incidence and morbidity time from specific AIDS illnesses in populations at high risk for death from these illnesses and other causes. The disease-death process has four-stages that can be recast as two sandwiching three-state multiple decrement processes. Non-parametric estimation of net incidence and morbidity time with error bounds are achieved from these sandwiching models through modification of methods from Aalen and Greenwood, and bootstrapping. An application to immunosuppressed HIV-1 infected homosexual men reveals that cytomegalovirus disease, Kaposi's sarcoma and Pneumocystis pneumonia are likely to occur and cause significant morbidity time.

  12. A public finance analysis of multiple reserve requirements

    OpenAIRE

    Espinosa-Vega, Marco; Russell, Steven

    1998-01-01

    This paper analyzes multiple reserve requirements of the type that have been imposed by a number of developing countries. We show that previous theoretical work on this topic has not succeeded in providing a social welfare rationale for the existence of multiple reserve requirements: in the basic reserve requirements model, any allocation that can be supported by a multiple-reserves regime can also be supported by a single-bond reserve requirement. We go on to present extended versions of the...

  13. Dietary patterns derived with multiple methods from food diaries and breast cancer risk in the UK Dietary Cohort Consortium

    Science.gov (United States)

    Pot, Gerda K; Stephen, Alison M; Dahm, Christina C; Key, Timothy J; Cairns, Benjamin J; Burley, Victoria J; Cade, Janet E; Greenwood, Darren C; Keogh, Ruth H; Bhaniani, Amit; McTaggart, Alison; Lentjes, Marleen AH; Mishra, Gita; Brunner, Eric J; Khaw, Kay Tee

    2015-01-01

    Background/ Objectives In spite of several studies relating dietary patterns to breast cancer risk, evidence so far remains inconsistent. This study aimed to investigate associations of dietary patterns derived with three different methods with breast cancer risk. Subjects/ Methods The Mediterranean Diet Score (MDS), principal components analyses (PCA) and reduced rank regression (RRR) were used to derive dietary patterns in a case-control study of 610 breast cancer cases and 1891 matched controls within 4 UK cohort studies. Dietary intakes were collected prospectively using 4-to 7-day food diaries and resulting food consumption data were grouped into 42 food groups. Conditional logistic regression models were used to estimate odds ratios (ORs) for associations between pattern scores and breast cancer risk adjusting for relevant covariates. A separate model was fitted for post-menopausal women only. Results The MDS was not associated with breast cancer risk (OR comparing 1st tertile with 3rd 1.20 (95% CI 0.92; 1.56)), nor the first PCA-derived dietary pattern, explaining 2.7% of variation of diet and characterized by cheese, crisps and savoury snacks, legumes, nuts and seeds (OR 1.18 (95% CI 0.91; 1.53)). The first RRR-derived pattern, a ‘high-alcohol’ pattern, was associated with a higher risk of breast cancer (OR 1.27; 95% CI 1.00; 1.62), which was most pronounced in post-menopausal women (OR 1.46 (95% CI 1.08; 1.98). Conclusions A ‘high-alcohol’ dietary pattern derived with RRR was associated with an increased breast cancer risk; no evidence of associations of other dietary patterns with breast cancer risk was observed in this study. PMID:25052230

  14. Integrating Multiple Data Views for Improved Malware Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Blake H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-31

    Exploiting multiple views of a program makes obfuscating the intended behavior of a program more difficult allowing for better performance in classification, clustering, and phylogenetic reconstruction.

  15. Active neutron multiplicity analysis and Monte Carlo calculations

    International Nuclear Information System (INIS)

    Krick, M.S.; Ensslin, N.; Langner, D.G.; Miller, M.C.; Siebelist, R.; Stewart, J.E.; Ceo, R.N.; May, P.K.; Collins, L.L. Jr

    1994-01-01

    Active neutron multiplicity measurements of high-enrichment uranium metal and oxide samples have been made at Los Alamos and Y-12. The data from the measurements of standards at Los Alamos were analyzed to obtain values for neutron multiplication and source-sample coupling. These results are compared to equivalent results obtained from Monte Carlo calculations. An approximate relationship between coupling and multiplication is derived and used to correct doubles rates for multiplication and coupling. The utility of singles counting for uranium samples is also examined

  16. Upper limb movement analysis during gait in multiple sclerosis patients.

    Science.gov (United States)

    Elsworth-Edelsten, Charlotte; Bonnefoy-Mazure, Alice; Laidet, Magali; Armand, Stephane; Assal, Frederic; Lalive, Patrice; Allali, Gilles

    2017-08-01

    Gait disorders in multiple sclerosis (MS) are well studied; however, no previous study has described upper limb movements during gait. However, upper limb movements have an important role during locomotion and can be altered in MS patients due to direct MS lesions or mechanisms of compensation. The aim of this study was to describe the arm movements during gait in a population of MS patients with low disability compared with a healthy control group. In this observational study we analyzed the arm movements during gait in 52 outpatients (mean age: 39.7±9.6years, female: 40%) with relapsing-remitting MS with low disability (mean EDSS: 2±1) and 25 healthy age-matched controls using a 3-dimension gait analysis. MS patients walked slower, with increased mean elbow flexion and decreased amplitude of elbow flexion (ROM) compared to the control group, whereas shoulder and hand movements were similar to controls. These differences were not explained by age or disability. Upper limb alterations in movement during gait in MS patients with low disability can be characterized by an increase in mean elbow flexion and a decrease in amplitude (ROM) for elbow flexion/extension. This upper limb movement pattern should be considered as a new component of gait disorders in MS and may reflect subtle motor deficits or the use of compensatory mechanisms. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Multiple criteria decision analysis for health technology assessment.

    Science.gov (United States)

    Thokala, Praveen; Duenas, Alejandra

    2012-12-01

    Multicriteria decision analysis (MCDA) has been suggested by some researchers as a method to capture the benefits beyond quality adjusted life-years in a transparent and consistent manner. The objectives of this article were to analyze the possible application of MCDA approaches in health technology assessment and to describe their relative advantages and disadvantages. This article begins with an introduction to the most common types of MCDA models and a critical review of state-of-the-art methods for incorporating multiple criteria in health technology assessment. An overview of MCDA is provided and is compared against the current UK National Institute for Health and Clinical Excellence health technology appraisal process. A generic MCDA modeling approach is described, and the different MCDA modeling approaches are applied to a hypothetical case study. A comparison of the different MCDA approaches is provided, and the generic issues that need consideration before the application of MCDA in health technology assessment are examined. There are general practical issues that might arise from using an MCDA approach, and it is suggested that appropriate care be taken to ensure the success of MCDA techniques in the appraisal process. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  18. Seismic structural response analysis for multiple support excitation

    International Nuclear Information System (INIS)

    Shaw, D.E.

    1975-01-01

    In the seismic analysis of nuclear power plant equipment such as piping systems situations often arise in which piping systems span between adjacent structures or between different elevations in the same structure. Owing to the differences in the seismic time history response of different structures or different elevations of the same structure, the input support motion will differ for different supports. The concept of a frequency dependent participation factor and rotational response spectra accounting for phase differences between support excitations is developed by using classical equations of motion to formulate the seismic response of a structure subjected to multiple support excitation. The essence of the method lies in describing the seismic excitation of a multiply excited structure in terms of translational and rotational spectra used at every support and a frequency dependent spatial distribution function derived from the phase relationships of the different support time histories. In this manner it is shown that frequency dependent participation factors can be derived from the frequency dependent distribution functions. Examples are shown and discussed relative to closed form solutions and the state-of-the-art techniques presently being used for the solution of problems of multiply excited structures

  19. A Multiple-Scale Analysis of Evaporation Induced Marangoni Convection

    KAUST Repository

    Hennessy, Matthew G.

    2013-04-23

    This paper considers the stability of thin liquid layers of binary mixtures of a volatile (solvent) species and a nonvolatile (polymer) species. Evaporation leads to a depletion of the solvent near the liquid surface. If surface tension increases for lower solvent concentrations, sufficiently strong compositional gradients can lead to Bénard-Marangoni-type convection that is similar to the kind which is observed in films that are heated from below. The onset of the instability is investigated by a linear stability analysis. Due to evaporation, the base state is time dependent, thus leading to a nonautonomous linearized system which impedes the use of normal modes. However, the time scale for the solvent loss due to evaporation is typically long compared to the diffusive time scale, so a systematic multiple scales expansion can be sought for a finite-dimensional approximation of the linearized problem. This is determined to leading and to next order. The corrections indicate that the validity of the expansion does not depend on the magnitude of the individual eigenvalues of the linear operator, but it requires these eigenvalues to be well separated. The approximations are applied to analyze experiments by Bassou and Rharbi with polystyrene/toluene mixtures [Langmuir, 25 (2009), pp. 624-632]. © 2013 Society for Industrial and Applied Mathematics.

  20. Parallel multiple instance learning for extremely large histopathology image analysis.

    Science.gov (United States)

    Xu, Yan; Li, Yeshu; Shen, Zhengyang; Wu, Ziwei; Gao, Teng; Fan, Yubo; Lai, Maode; Chang, Eric I-Chao

    2017-08-03

    Histopathology images are critical for medical diagnosis, e.g., cancer and its treatment. A standard histopathology slice can be easily scanned at a high resolution of, say, 200,000×200,000 pixels. These high resolution images can make most existing imaging processing tools infeasible or less effective when operated on a single machine with limited memory, disk space and computing power. In this paper, we propose an algorithm tackling this new emerging "big data" problem utilizing parallel computing on High-Performance-Computing (HPC) clusters. Experimental results on a large-scale data set (1318 images at a scale of 10 billion pixels each) demonstrate the efficiency and effectiveness of the proposed algorithm for low-latency real-time applications. The framework proposed an effective and efficient system for extremely large histopathology image analysis. It is based on the multiple instance learning formulation for weakly-supervised learning for image classification, segmentation and clustering. When a max-margin concept is adopted for different clusters, we obtain further improvement in clustering performance.

  1. Microseismic Monitoring Design Optimization Based on Multiple Criteria Decision Analysis

    Science.gov (United States)

    Kovaleva, Y.; Tamimi, N.; Ostadhassan, M.

    2017-12-01

    Borehole microseismic monitoring of hydraulic fracture treatments of unconventional reservoirs is a widely used method in the oil and gas industry. Sometimes, the quality of the acquired microseismic data is poor. One of the reasons for poor data quality is poor survey design. We attempt to provide a comprehensive and thorough workflow, using multiple criteria decision analysis (MCDA), to optimize planning micriseismic monitoring. So far, microseismic monitoring has been used extensively as a powerful tool for determining fracture parameters that affect the influx of formation fluids into the wellbore. The factors that affect the quality of microseismic data and their final results include average distance between microseismic events and receivers, complexity of the recorded wavefield, signal-to-noise ratio, data aperture, etc. These criteria often conflict with each other. In a typical microseismic monitoring, those factors should be considered to choose the best monitoring well(s), optimum number of required geophones, and their depth. We use MDCA to address these design challenges and develop a method that offers an optimized design out of all possible combinations to produce the best data acquisition results. We believe that this will be the first research to include the above-mentioned factors in a 3D model. Such a tool would assist companies and practicing engineers in choosing the best design parameters for future microseismic projects.

  2. A Multiple-Scale Analysis of Evaporation Induced Marangoni Convection

    KAUST Repository

    Hennessy, Matthew G.; Mü nch, Andreas

    2013-01-01

    This paper considers the stability of thin liquid layers of binary mixtures of a volatile (solvent) species and a nonvolatile (polymer) species. Evaporation leads to a depletion of the solvent near the liquid surface. If surface tension increases for lower solvent concentrations, sufficiently strong compositional gradients can lead to Bénard-Marangoni-type convection that is similar to the kind which is observed in films that are heated from below. The onset of the instability is investigated by a linear stability analysis. Due to evaporation, the base state is time dependent, thus leading to a nonautonomous linearized system which impedes the use of normal modes. However, the time scale for the solvent loss due to evaporation is typically long compared to the diffusive time scale, so a systematic multiple scales expansion can be sought for a finite-dimensional approximation of the linearized problem. This is determined to leading and to next order. The corrections indicate that the validity of the expansion does not depend on the magnitude of the individual eigenvalues of the linear operator, but it requires these eigenvalues to be well separated. The approximations are applied to analyze experiments by Bassou and Rharbi with polystyrene/toluene mixtures [Langmuir, 25 (2009), pp. 624-632]. © 2013 Society for Industrial and Applied Mathematics.

  3. Smoking and multiple sclerosis: an updated meta-analysis.

    Directory of Open Access Journals (Sweden)

    Adam E Handel

    2011-01-01

    Full Text Available Multiple sclerosis (MS is a leading cause of disability in young adults. Susceptibility to MS is determined by environmental exposure on the background of genetic risk factors. A previous meta-analysis suggested that smoking was an important risk factor for MS but many other studies have been published since then.We performed a Medline search to identify articles published that investigated MS risk following cigarette smoking. A total of 14 articles were included in this study. This represented data on 3,052 cases and 457,619 controls. We analysed these studies in both a conservative (limiting our analysis to only those where smoking behaviour was described prior to disease onset and non-conservative manner. Our results show that smoking is associated with MS susceptibility (conservative: risk ratio (RR 1.48, 95% confidence interval (CI 1.35-1.63, p < 10⁻¹⁵; non-conservative: RR 1.52, 95% CI 1.39-1.66, p < 10⁻¹⁹. We also analysed 4 studies reporting risk of secondary progression in MS and found that this fell just short of statistical significance with considerable heterogeneity (RR 1.88, 95% CI 0.98-3.61, p = 0.06.Our results demonstrate that cigarette smoking is important in determining MS susceptibility but the effect on the progression of disease is less certain. Further work is needed to understand the mechanism behind this association and how smoking integrates with other established risk factors.

  4. Extension of ship accident analysis to multiple-package shipments

    International Nuclear Information System (INIS)

    Mills, G.S.; Neuhauser, K.S.

    1997-11-01

    Severe ship accidents and the probability of radioactive material release from spent reactor fuel casks were investigated previously. Other forms of RAM, e.g., plutonium oxide powder, may be shipped in large numbers of packagings rather than in one to a few casks. These smaller, more numerous packagings are typically placed in ISO containers for ease of handling, and several ISO containers may be placed in one of several holds of a cargo ship. In such cases, the size of a radioactive release resulting from a severe collision with another ship is determined not by the likelihood of compromising a single, robust package but by the probability that a certain fraction of 10's or 100's of individual packagings is compromised. The previous analysis involved a statistical estimation of the frequency of accidents which would result in damage to a cask located in one of seven cargo holds in a collision with another ship. The results were obtained in the form of probabilities (frequencies) of accidents of increasing severity and of release fractions for each level of severity. This paper describes an extension of the same general method in which the multiple packages are assumed to be compacted by an intruding ship's bow until there is no free space in the hold. At such a point, the remaining energy of the colliding ship is assumed to be dissipated by progressively crushing the RAM packagings and the probability of a particular fraction of package failures is estimated by adaptation of the statistical method used previously. The parameters of a common, well characterized packaging, the 6M with 2R inner containment vessel, were employed as an illustrative example of this analysis method. However, the method is readily applicable to other packagings for which crush strengths have been measured or can be estimated with satisfactory confidence

  5. Extension of ship accident analysis to multiple-package shipments

    International Nuclear Information System (INIS)

    Mills, G.S.; Neuhauser, K.S.

    1998-01-01

    Severe ship accidents and the probability of radioactive material release from spent reactor fuel casks were investigated previously (Spring, 1995). Other forms of RAM, e.g., plutonium oxide powder, may be shipped in large numbers of packagings rather than in one to a few casks. These smaller, more numerous packagings are typically placed in ISO containers for ease of handling, and several ISO containers may be placed in one of several holds of a cargo ship. In such cases, the size of a radioactive release resulting from a severe collision with another ship is determined not by the likelihood of compromising a single, robust package but by the probability that a certain fraction of 10's or 100's of individual packagings is compromised. The previous analysis (Spring, 1995) involved a statistical estimation of the frequency of accidents which would result in damage to a cask located in one of seven cargo holds in a collision with another ship. The results were obtained in the form of probabilities (frequencies) of accidents of increasing severity and of release fractions for each level of severity. This paper describes an extension of the same general method in which the multiple packages are assumed to be compacted by an intruding ship's bow until there is no free space in the hold. At such a point, the remaining energy of the colliding ship is assumed to be dissipated by progressively crushing the RAM packagings and the probability of a particular fraction of package failures is estimated by adaptation of the statistical method used previously. The parameters of a common, well-characterized packaging, the 6M with 2R inner containment vessel, were employed as an illustrative example of this analysis method. However, the method is readily applicable to other packagings for which crush strengths have been measured or can be estimated with satisfactory confidence. (authors)

  6. Analysis of Plasminogen Genetic Variants in Multiple Sclerosis Patients

    Directory of Open Access Journals (Sweden)

    A. Dessa Sadovnick

    2016-07-01

    Full Text Available Multiple sclerosis (MS is a prevalent neurological disease of complex etiology. Here, we describe the characterization of a multi-incident MS family that nominated a rare missense variant (p.G420D in plasminogen (PLG as a putative genetic risk factor for MS. Genotyping of PLG p.G420D (rs139071351 in 2160 MS patients, and 886 controls from Canada, identified 10 additional probands, two sporadic patients and one control with the variant. Segregation in families harboring the rs139071351 variant, identified p.G420D in 26 out of 30 family members diagnosed with MS, 14 unaffected parents, and 12 out of 30 family members not diagnosed with disease. Despite considerably reduced penetrance, linkage analysis supports cosegregation of PLG p.G420D and disease. Genotyping of PLG p.G420D in 14446 patients, and 8797 controls from Canada, France, Spain, Germany, Belgium, and Austria failed to identify significant association with disease (P = 0.117, despite an overall higher prevalence in patients (OR = 1.32; 95% CI = 0.93–1.87. To assess whether additional rare variants have an effect on MS risk, we sequenced PLG in 293 probands, and genotyped all rare variants in cases and controls. This analysis identified nine rare missense variants, and although three of them were exclusively observed in MS patients, segregation does not support pathogenicity. PLG is a plausible biological candidate for MS owing to its involvement in immune system response, blood-brain barrier permeability, and myelin degradation. Moreover, components of its activation cascade have been shown to present increased activity or expression in MS patients compared to controls; further studies are needed to clarify whether PLG is involved in MS susceptibility.

  7. Analysis of Plasminogen Genetic Variants in Multiple Sclerosis Patients

    Science.gov (United States)

    Sadovnick, A. Dessa; Traboulsee, Anthony L.; Bernales, Cecily Q.; Ross, Jay P.; Forwell, Amanda L.; Yee, Irene M.; Guillot-Noel, Lena; Fontaine, Bertrand; Cournu-Rebeix, Isabelle; Alcina, Antonio; Fedetz, Maria; Izquierdo, Guillermo; Matesanz, Fuencisla; Hilven, Kelly; Dubois, Bénédicte; Goris, An; Astobiza, Ianire; Alloza, Iraide; Antigüedad, Alfredo; Vandenbroeck, Koen; Akkad, Denis A.; Aktas, Orhan; Blaschke, Paul; Buttmann, Mathias; Chan, Andrew; Epplen, Joerg T.; Gerdes, Lisa-Ann; Kroner, Antje; Kubisch, Christian; Kümpfel, Tania; Lohse, Peter; Rieckmann, Peter; Zettl, Uwe K.; Zipp, Frauke; Bertram, Lars; Lill, Christina M; Fernandez, Oscar; Urbaneja, Patricia; Leyva, Laura; Alvarez-Cermeño, Jose Carlos; Arroyo, Rafael; Garagorri, Aroa M.; García-Martínez, Angel; Villar, Luisa M.; Urcelay, Elena; Malhotra, Sunny; Montalban, Xavier; Comabella, Manuel; Berger, Thomas; Fazekas, Franz; Reindl, Markus; Schmied, Mascha C.; Zimprich, Alexander; Vilariño-Güell, Carles

    2016-01-01

    Multiple sclerosis (MS) is a prevalent neurological disease of complex etiology. Here, we describe the characterization of a multi-incident MS family that nominated a rare missense variant (p.G420D) in plasminogen (PLG) as a putative genetic risk factor for MS. Genotyping of PLG p.G420D (rs139071351) in 2160 MS patients, and 886 controls from Canada, identified 10 additional probands, two sporadic patients and one control with the variant. Segregation in families harboring the rs139071351 variant, identified p.G420D in 26 out of 30 family members diagnosed with MS, 14 unaffected parents, and 12 out of 30 family members not diagnosed with disease. Despite considerably reduced penetrance, linkage analysis supports cosegregation of PLG p.G420D and disease. Genotyping of PLG p.G420D in 14446 patients, and 8797 controls from Canada, France, Spain, Germany, Belgium, and Austria failed to identify significant association with disease (P = 0.117), despite an overall higher prevalence in patients (OR = 1.32; 95% CI = 0.93–1.87). To assess whether additional rare variants have an effect on MS risk, we sequenced PLG in 293 probands, and genotyped all rare variants in cases and controls. This analysis identified nine rare missense variants, and although three of them were exclusively observed in MS patients, segregation does not support pathogenicity. PLG is a plausible biological candidate for MS owing to its involvement in immune system response, blood-brain barrier permeability, and myelin degradation. Moreover, components of its activation cascade have been shown to present increased activity or expression in MS patients compared to controls; further studies are needed to clarify whether PLG is involved in MS susceptibility. PMID:27194806

  8. An international contrast of rates of placental abruption: an age-period-cohort analysis.

    Directory of Open Access Journals (Sweden)

    Cande V Ananth

    Full Text Available Although rare, placental abruption is implicated in disproportionately high rates of perinatal morbidity and mortality. Understanding geographic and temporal variations may provide insights into possible amenable factors of abruption. We examined abruption frequencies by maternal age, delivery year, and maternal birth cohorts over three decades across seven countries.Women that delivered in the US (n = 863,879; 1979-10, Canada (4 provinces, n = 5,407,463; 1982-11, Sweden (n = 3,266,742; 1978-10, Denmark (n = 1,773,895; 1978-08, Norway (n = 1,780,271, 1978-09, Finland (n = 1,411,867; 1987-10, and Spain (n = 6,151,508; 1999-12 were analyzed. Abruption diagnosis was based on ICD coding. Rates were modeled using Poisson regression within the framework of an age-period-cohort analysis, and multi-level models to examine the contribution of smoking in four countries.Abruption rates varied across the seven countries (3-10 per 1000, Maternal age showed a consistent J-shaped pattern with increased rates at the extremes of the age distribution. In comparison to births in 2000, births after 2000 in European countries had lower abruption rates; in the US there was an increase in rate up to 2000 and a plateau thereafter. No birth cohort effects were evident. Changes in smoking prevalence partially explained the period effect in the US (P = 0.01 and Sweden (P<0.01.There is a strong maternal age effect on abruption. While the abruption rate has plateaued since 2000 in the US, all other countries show declining rates. These findings suggest considerable variation in abruption frequencies across countries; differences in the distribution of risk factors, especially smoking, may help guide policy to reduce abruption rates.

  9. An international contrast of rates of placental abruption: an age-period-cohort analysis.

    Science.gov (United States)

    Ananth, Cande V; Keyes, Katherine M; Hamilton, Ava; Gissler, Mika; Wu, Chunsen; Liu, Shiliang; Luque-Fernandez, Miguel Angel; Skjærven, Rolv; Williams, Michelle A; Tikkanen, Minna; Cnattingius, Sven

    2015-01-01

    Although rare, placental abruption is implicated in disproportionately high rates of perinatal morbidity and mortality. Understanding geographic and temporal variations may provide insights into possible amenable factors of abruption. We examined abruption frequencies by maternal age, delivery year, and maternal birth cohorts over three decades across seven countries. Women that delivered in the US (n = 863,879; 1979-10), Canada (4 provinces, n = 5,407,463; 1982-11), Sweden (n = 3,266,742; 1978-10), Denmark (n = 1,773,895; 1978-08), Norway (n = 1,780,271, 1978-09), Finland (n = 1,411,867; 1987-10), and Spain (n = 6,151,508; 1999-12) were analyzed. Abruption diagnosis was based on ICD coding. Rates were modeled using Poisson regression within the framework of an age-period-cohort analysis, and multi-level models to examine the contribution of smoking in four countries. Abruption rates varied across the seven countries (3-10 per 1000), Maternal age showed a consistent J-shaped pattern with increased rates at the extremes of the age distribution. In comparison to births in 2000, births after 2000 in European countries had lower abruption rates; in the US there was an increase in rate up to 2000 and a plateau thereafter. No birth cohort effects were evident. Changes in smoking prevalence partially explained the period effect in the US (P = 0.01) and Sweden (Prate has plateaued since 2000 in the US, all other countries show declining rates. These findings suggest considerable variation in abruption frequencies across countries; differences in the distribution of risk factors, especially smoking, may help guide policy to reduce abruption rates.

  10. Application of Probabilistic Multiple-Bias Analyses to a Cohort- and a Case-Control Study on the Association between Pandemrix™ and Narcolepsy.

    Directory of Open Access Journals (Sweden)

    Kaatje Bollaerts

    Full Text Available An increase in narcolepsy cases was observed in Finland and Sweden towards the end of the 2009 H1N1 influenza pandemic. Preliminary observational studies suggested a temporal link with the pandemic influenza vaccine Pandemrix™, leading to a number of additional studies across Europe. Given the public health urgency, these studies used readily available retrospective data from various sources. The potential for bias in such settings was generally acknowledged. Although generally advocated by key opinion leaders and international health authorities, no systematic quantitative assessment of the potential joint impact of biases was undertaken in any of these studies.We applied bias-level multiple-bias analyses to two of the published narcolepsy studies: a pediatric cohort study from Finland and a case-control study from France. In particular, we developed Monte Carlo simulation models to evaluate a potential cascade of biases, including confounding by age, by indication and by natural H1N1 infection, selection bias, disease- and exposure misclassification. All bias parameters were evidence-based to the extent possible.Given the assumptions used for confounding, selection bias and misclassification, the Finnish rate ratio of 13.78 (95% CI: 5.72-28.11 reduced to a median value of 6.06 (2.5th- 97.5th percentile: 2.49-15.1 and the French odds ratio of 5.43 (95% CI: 2.6-10.08 to 1.85 (2.5th-97.5th percentile: 0.85-4.08.We illustrate multiple-bias analyses using two studies on the Pandemrix™-narcolepsy association and advocate their use to better understand the robustness of study findings. Based on our multiple-bias models, the observed Pandemrix™-narcolepsy association consistently persists in the Finnish study. For the French study, the results of our multiple-bias models were inconclusive.

  11. Containment analysis of the 9975 transportation package with multiple barriers

    International Nuclear Information System (INIS)

    Vinson, D.W.

    2000-01-01

    A containment analysis has been performed for the scenario of non-routine transfer of a damaged 9975 package containing plutonium metal from K-area monitored storage to F-area on the Savannah River Site. A multiple barrier system with each barrier having a defined leakage rate of less than 1times10 -3 cm 3 /sec of air at Standard Temperature and Pressure was analyzed to determine the number of barriers needed to transport the package under normal transportation conditions to meet transportation requirements for containment. The barrier system was analyzed parametrically to achieve a composite system that met the federal requirements for the maximum permissible release rate given in Title 10 of the Code of Federal Regulations, Part 71. The multiple barrier system acts to retard the release of radioactivity. That is, a build-up in the radioactivity release rate occurs with time. For example, a system with three barriers (e.g., sealed plastic barrier) with a total free volume of 4,500 cm 3 could be transported for a total time of up to approximately 10 days with a release rate within the permissible rate. Additional number of barriers, or volume of the barriers, or both, would extend to this period of time. For example, a system with seven barriers with a total free volume of 4,500 cm 3 could be transported for up to 100 days. Plastic bags are one type of barrier used in movement of radioactive materials and capable of achieving a leak rate of 1times10 -3 cm 3 /sec of air at STP. Low-density polyethylene bags can withstand high temperature (up to 180 degrees C); a barrier thickness of 10 mils should be suitable for the barrier system. Additional requirements for barriers are listed in Section 4.2 of this report. Container testing per ANSI N14.5 is required to demonstrate leak rates for the individual barriers of less than 1times10 -3 cm 3 /sec

  12. Childhood Mourning: Prospective Case Analysis of Multiple Losses

    Science.gov (United States)

    Kaufman, Kenneth R.; Kaufman, Nathaniel D.

    2005-01-01

    Multiple losses within short time periods make one question life and can exponentially influence one's coping skills. But what are the effects on a child and what should be done when the next loss occurs? This case addresses the multiple losses suffered by a child while assessing coping skills of the child and coping strategies used by the parents…

  13. Reliability and acceptability of the Multiple Sclerosis Quality of Life-29 questionnaire in an English-speaking cohort.

    Science.gov (United States)

    Baker, Georgina; Nair, Krishnan Padmakumari Sivaraman; Baster, Kathleen; Rosato, Rosalba; Solari, Alessandra

    2018-05-01

    Multiple Sclerosis Quality-of-Life Questionnaire-54 (MSQoL-54) is a disease-specific instrument for assessing health-related quality of life (HRQoL). Due to the number of items, the time taken to complete it is long. A shorter 29-item version, Multiple Sclerosis Quality-of-Life Questionnaire-29 (MSQoL-29) is yet to be evaluated in English. To assess reliability and acceptability of English version of MSQoL-29. Among 100 participants with MS who first completed both MSQoL-54 and MSQoL-29, 91 completed MSQoL-29 after 4-8 weeks. We looked for internal consistency (Cronbach's alpha), acceptability, reliability (intraclass correlation coefficients (ICCs)) and agreement (Bland-Altman plots). ICCs were strongly positive between MSQoL-54 and MSQoL-29 (Physical Health Composite (PHC) -ICC = 0.914, confidence interval (CI) = 0.872-0.942; Mental Health Composite (MHC) - ICC = 0.875, CI = 0.814-0.916) and between the two MSQoL-29 (PHC - ICC = 0.970, CI = 0.955-0.980; MHC - ICC = 0.937, CI = 0.904-0.958). On Bland-Altman plots, the MSQoL-29 scores of 95% of participants during two visits were within the limits of agreement (LOAs). Time taken to complete MSQoL-29 was 7.2 ± 2.9 minutes and MSQoL-54 was 19.79 ± 5.4 minutes ( p = 0.0001). MSQoL-29 has good test-retest reliability in English-speaking population and was quicker to complete.

  14. Systematically missing confounders in individual participant data meta-analysis of observational cohort studies

    NARCIS (Netherlands)

    Jackson, D.; White, I.; Kostis, J.B.; Wilson, A.C.; Folsom, A.R.; Feskens, E.J.M.

    2009-01-01

    One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an

  15. Systematically missing confounders in individual participant data meta-analysis of observational cohort studies

    DEFF Research Database (Denmark)

    Jackson, D.; White, I.; Kostis, J.B.

    2009-01-01

    One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an...

  16. The Distribution of Income and Taxes/Transfers In Canada: A Cohort Analysis

    Directory of Open Access Journals (Sweden)

    Daria Crisan

    2015-02-01

    Full Text Available Who pays and how much? These are crucial questions for any tax system and, given the complexity of the economy, they are also among the most difficult to answer. This paper undertakes an analysis of the distribution of taxes and transfers in Canada using a static approach based on annual income combined with the novel approach of breaking down taxpayers by age cohort. The paper examines how tax rates net of transfers differ by age and income group, and how those rates change over taxpayers’ lifetimes. It clearly reveals the progressive nature of Canada’s tax system. In our base case scenario, when all age cohorts are considered together and transfers are treated as negative taxes, the first two quintiles of the income distribution are net recipients of government transfers with negative net tax rates equal to about -48 percent for the first quintile and -33 percent for the second quintile. For middle to high-income individuals net tax rates are positive and increase with income, from 10 percent for the median group, to 24 percent for the fourth quintile and 34 percent for the fifth quintile. Looking at net tax rates by age cohort, we find that overall the bottom 20 percent of the income distribution is a net recipient of fiscal transfers at all ages. However, on average for individuals 65 and over all but the top 20 percent of the income distribution are net recipients of fiscal transfers, with negative net tax rates. The age related redistributive nature of Canada’s tax system is further emphasized by an examination of the Gini coefficients for each age cohort, calculated here for the first time. Starting at age 30, before taxes and transfers income inequality is found to rise monotonically with age, leveling off at 65. Taxes and transfers reduce the degree of income inequality significantly for all ages, but substantially more so for the elderly due to age related features of the tax and transfer system. If redistribution can be thought

  17. Genomic copy number analysis of Chernobyl papillary thyroid carcinoma in the Ukrainian–American Cohort

    Science.gov (United States)

    Selmansberger, Martin; Braselmann, Herbert; Hess, Julia; Bogdanova, Tetiana; Abend, Michael; Tronko, Mykola; Brenner, Alina; Zitzelsberger, Horst; Unger, Kristian

    2015-01-01

    One of the major consequences of the 1986 Chernobyl reactor accident was a dramatic increase in papillary thyroid carcinoma (PTC) incidence, predominantly in patients exposed to the radioiodine fallout at young age. The present study is the first on genomic copy number alterations (CNAs) of PTCs of the Ukrainian–American cohort (UkrAm) generated by array comparative genomic hybridization (aCGH). Unsupervised hierarchical clustering of CNA profiles revealed a significant enrichment of a subgroup of patients with female gender, long latency (>17 years) and negative lymph node status. Further, we identified single CNAs that were significantly associated with latency, gender, radiation dose and BRAF V600E mutation status. Multivariate analysis revealed no interactions but additive effects of parameters gender, latency and dose on CNAs. The previously identified radiation-associated gain of the chromosomal bands 7q11.22-11.23 was present in 29% of cases. Moreover, comparison of our radiation-associated PTC data set with the TCGA data set on sporadic PTCs revealed altered copy numbers of the tumor driver genes NF2 and CHEK2. Further, we integrated the CNA data with transcriptomic data that were available on a subset of the herein analyzed cohort and did not find statistically significant associations between the two molecular layers. However, applying hierarchical clustering on a ‘BRAF-like/RAS-like’ transcriptome signature split the cases into four groups, one of which containing all BRAF-positive cases validating the signature in an independent data set. PMID:26320103

  18. Predictive test for chemotherapy response in resectable gastric cancer: a multi-cohort, retrospective analysis.

    Science.gov (United States)

    Cheong, Jae-Ho; Yang, Han-Kwang; Kim, Hyunki; Kim, Woo Ho; Kim, Young-Woo; Kook, Myeong-Cherl; Park, Young-Kyu; Kim, Hyung-Ho; Lee, Hye Seung; Lee, Kyung Hee; Gu, Mi Jin; Kim, Ha Yan; Lee, Jinae; Choi, Seung Ho; Hong, Soonwon; Kim, Jong Won; Choi, Yoon Young; Hyung, Woo Jin; Jang, Eunji; Kim, Hyeseon; Huh, Yong-Min; Noh, Sung Hoon

    2018-05-01

    Adjuvant chemotherapy after surgery improves survival of patients with stage II-III, resectable gastric cancer. However, the overall survival benefit observed after adjuvant chemotherapy is moderate, suggesting that not all patients with resectable gastric cancer treated with adjuvant chemotherapy benefit from it. We aimed to develop and validate a predictive test for adjuvant chemotherapy response in patients with resectable, stage II-III gastric cancer. In this multi-cohort, retrospective study, we developed through a multi-step strategy a predictive test consisting of two rule-based classifier algorithms with predictive value for adjuvant chemotherapy response and prognosis. Exploratory bioinformatics analyses identified biologically relevant candidate genes in gastric cancer transcriptome datasets. In the discovery analysis, a four-gene, real-time RT-PCR assay was developed and analytically validated in formalin-fixed, paraffin-embedded (FFPE) tumour tissues from an internal cohort of 307 patients with stage II-III gastric cancer treated at the Yonsei Cancer Center with D2 gastrectomy plus adjuvant fluorouracil-based chemotherapy (n=193) or surgery alone (n=114). The same internal cohort was used to evaluate the prognostic and chemotherapy response predictive value of the single patient classifier genes using associations with 5-year overall survival. The results were validated with a subset (n=625) of FFPE tumour samples from an independent cohort of patients treated in the CLASSIC trial (NCT00411229), who received D2 gastrectomy plus capecitabine and oxaliplatin chemotherapy (n=323) or surgery alone (n=302). The primary endpoint was 5-year overall survival. We identified four classifier genes related to relevant gastric cancer features (GZMB, WARS, SFRP4, and CDX1) that formed the single patient classifier assay. In the validation cohort, the prognostic single patient classifier (based on the expression of GZMB, WARS, and SFRP4) identified 79 (13%) of 625

  19. Maternal SSRI discontinuation, use, psychiatric disorder and the risk of autism in children: a meta-analysis of cohort studies.

    Science.gov (United States)

    Kaplan, Yusuf Cem; Keskin-Arslan, Elif; Acar, Selin; Sozmen, Kaan

    2017-12-01

    We undertook an exclusive meta-analysis of cohort studies investigating the possible link between prenatal selective serotonin reuptake inhibitor (SSRI) exposure and autism spectrum disorders (ASD) in children to further investigate our previous suggestion of confounding by indication. The point estimates regarding the following cohorts were extracted and pooled: (1) pregnant women who discontinued SSRI until 3 months before pregnancy; (2) pregnant women who were exposed to SSRI during pregnancy; and (3) pregnant women with maternal psychiatric disorder but no exposure to SSRI during pregnancy. Although the pooled point estimate of the first cohort showed a trend for increase, it did not reach significance. The pooled point estimates of the latter cohorts showed a significant association with ASD which strengthens our previous suggestion of confounding by indication. Future studies should be adequately designed to differentiate whether the previously suggested association is a result of maternal psychiatric disorder or SSRI exposure or both. © 2017 The British Pharmacological Society.

  20. The association between job strain and coronary heart disease: a meta-analysis of prospective cohort studies.

    Science.gov (United States)

    Xu, Shuxian; Huang, Yuli; Xiao, Jiping; Zhu, Wenjing; Wang, Lulu; Tang, Hongfeng; Hu, Yunzhao; Liu, Tiebang

    2015-01-01

    Studies about work stress and the risk of coronary heart disease (CHD) have yielded inconsistent results. This meta-analysis aimed to investigate the association between job strain and the risk of CHD. We searched PubMed and Embase databases for studies reporting data on job strain and the risk of CHD. Studies were included if they reported multiple-adjusted relative risk (RR) with 95% confidence interval (CI) with respect to CHD from job strain. Fourteen prospective cohort studies comprising 232,767 participants were included. The risk of CHD was increased in high-strain (RR 1.26; 95% CI 1.12-1.41) and passive jobs (RR 1.14; 95% CI 1.02-1.29) but not in active jobs (RR 1.09; 95% CI 0.97-1.22), when compared with low-strain group. The increased risk of CHD in high-strain and passive jobs was mainly driven by studies with a follow-up duration of ≥ 10 years. Neither the low-control (RR 1.06; 95% CI 0.93-1.19) nor high-demand (RR 1.13; 95% CI 0.97-1.32) dimension was independently associated with the risk of CHD. Individuals with high-strain and passive jobs were more likely to experience a CHD event. Intervention programs incorporating individual and organizational levels are crucial for reducing job strain and the risk of CHD.

  1. Agreement analysis comparing iPad LCVA and Sloan testing in multiple sclerosis patients.

    Science.gov (United States)

    Sattarnezhad, Neda; Farrow, Samantha; Kimbrough, Dorlan; Glanz, Bonnie; Healy, Brian; Chitnis, Tanuja

    2017-06-01

    Visual symptoms are common in multiple sclerosis (MS). Low-contrast visual acuity (LCVA) testing using Sloan charts has demonstrated increased sensitivity for visual deficits compared to high-contrast acuity testing. Computerized testing of visual acuity may facilitate use in the clinic setting. To evaluate the agreement between an iPad-based and Sloan testing of LCVA in a cohort of MS patients. A total of 38 patients with relapsing-remitting MS were enrolled after providing informed written consent at Partners MS Center, Brigham and Women's hospital. Monocular LCVA was measured using retroilluminated Sloan chart and iPad-based LogMAR chart. Number of correct letters and agreement between two measurements were assessed for each eye using Bland-Altman analysis and paired t-test. For both eyes, there was no significant difference in number correct between the two measurements using a paired t-test, and there was high correlation between two measurements (oculus dextrus (OD) r = 0.89, p iPad-based LCVA test shows good agreement with Sloan testing in MS patients.

  2. Dementia knowledge assessment scale (DKAS): confirmatory factor analysis and comparative subscale scores among an international cohort.

    Science.gov (United States)

    Annear, Michael J; Toye, Chris; Elliott, Kate-Ellen J; McInerney, Frances; Eccleston, Claire; Robinson, Andrew

    2017-07-31

    Dementia is a life-limiting condition that is increasing in global prevalence in line with population ageing. In this context, it is necessary to accurately measure dementia knowledge across a spectrum of health professional and lay populations with the aim of informing targeted educational interventions and improving literacy, care, and support. Building on prior exploratory analysis, which informed the development of the preliminarily valid and reliable version of the Dementia Knowledge Assessment Scale (DKAS), a Confirmatory Factor Analysis (CFA) was performed to affirm construct validity and proposed subscales to further increase the measure's utility for academics and educators. A large, de novo sample of 3649 volunteer respondents to a dementia-related online course was recruited to evaluate the performance of the DKAS and its proposed subscales. Respondents represented diverse cohorts, including health professionals, students, and members of the general public. Analyses included CFA (using structural equation modelling), measures of internal consistency (α), and non-parametric tests of subscale correlation (Spearman Correlation) and score differences between cohorts (Kruskal-Wallis one-way analysis of variance). Findings of the CFA supported a 25-item, four-factor model for the DKAS with two items removed due to poor performance and one item moved between factors. The resultant model exhibited good reliability (α = .85; ω h  = .87; overall scale), with acceptable subscale internal consistency (α ≥ .65; subscales). Subscales showed acceptable correlation without any indication of redundancy. Finally, total and DKAS subscale scores showed good discrimination between cohorts of respondents who would be anticipated to hold different levels of knowledge on the basis of education or experience related to dementia. The DKAS has been confirmed as a reliable and valid measure of dementia knowledge for diverse populations that is capable of elucidating

  3. Return-to-work for multiple jobholders with a work-related musculoskeletal disorder: A population-based, matched cohort in British Columbia.

    Science.gov (United States)

    Maas, Esther T; Koehoorn, Mieke; McLeod, Christopher B

    2018-01-01

    Multiple jobholders (MJHs) have a higher risk of injury compared to single jobholders (SJHs), but it is unknown if return-to-work (RTW) after a work injury is affected by multiple jobholding. This study examined the association between multiple versus single jobholding and time to RTW for workers with a work-related musculoskeletal disorder (MSD). We used administrative workers' compensation data to identify injured workers with an accepted MSD lost-time claim between 2010-2014 in British Columbia, Canada (n = 125,639 SJHs and 9,029 MJHs). The outcome was days until RTW during twelve months after the first day of time-loss. The MJH and SJH cohorts were balanced using coarsened exact matching that yielded a final matched cohort of 8,389 MJHs and 8,389 SJHs. The outcome was estimated with Cox regression, using piecewise models, and the hazard ratios were stratified by type of MSD, a serious injury indicator, gender, weekly workdays preceding MSD, and wage categories. MJHs were less likely to RTW compared to SJHs within the first six months after the first time-loss day, with greater and longer lasting effects for males, workers with a serious injury, and a higher wage. No difference between MJHs and SJHs was found for workers who had a six- or seven-day work week preceding MSD, for workers with dislocations, and for workers who were still off work after six months. Overall, MJHs with a workweek of maximum five days are disadvantaged compared to SJHs in terms of RTW following a work-related MSD within the first six months after the first time-loss day. This difference might be caused by more precarious job contracts for MJHs that challenges RTW because of lack of support for modified work, higher workload, and reduced likelihood that MJHs file a workers' compensation claim. Despite adjusting for type of MSD, severity of injury and occupation, the differences persisted for the vast majority of the study sample.

  4. Multiple measures of adiposity are associated with mean leukocyte telomere length in the northern Finland birth cohort 1966.

    Directory of Open Access Journals (Sweden)

    Jessica L Buxton

    Full Text Available Studies of leukocyte telomere length (LTL and adiposity have produced conflicting results, and the relationship between body mass index (BMI and telomere length throughout life remains unclear. We therefore tested association of adult LTL measured in 5,598 participants with: i childhood growth measures (BMI and age at adiposity rebound (AR; ii change in BMI from childhood to adulthood and iii adult BMI, waist-to-hip ratio (WHR, body adiposity index (BAI. Childhood BMI at AR was positively associated with LTL at 31 years in women (P = 0.041. Adult BMI and WHR in both men (P = 0.025 and P = 0.049, respectively and women (P = 0.029 and P = 0.008, respectively, and BAI in women (P = 0.021 were inversely associated with LTL at 31 years. An increase in standardised BMI between early childhood and adulthood was associated with shorter adult LTL in women (P = 0.008. We show that LTL is inversely associated with multiple measures of adiposity in both men and women. Additionally, BMI increase in women from childhood to adulthood is associated with shorter telomeres at age 31, potentially indicating accelerated biological ageing.

  5. No relevant impact of ambient temperature on disability measurements in a large cohort of patients with multiple sclerosis.

    Science.gov (United States)

    Stellmann, J-P; Young, K L; Vettorazzi, E; Pöttgen, J; Heesen, C

    2017-06-01

    Many patients with multiple sclerosis (MS) report a worsening of symptoms due to high ambient temperatures, but objective data about this association are rare and contradictory. The aim of this study was to investigate the influence of ambient temperature on standard clinical tests. We extracted the Symbol Digit Modality Test, Nine Hole Peg Test, Timed 25 Foot Walk (T25FW), Timed Tandem Walk, Expanded Disability Status Scale (EDSS) and quality-of-life items on cognition, fatigue and depression from our clinical database and matched them to historical temperatures. We used linear mixed-effect models to investigate the association between temperature and outcomes. A total of 1254 patients with MS (mean age, 42.7 years; 69.9% females; 52.1% relapsing-remitting MS, mean EDSS, 3.8) had 5751 assessments between 1996 and 2012. We observed a worsening in the T25FW with higher ambient temperatures in moderately disabled patients (EDSS ≥ 4) but not in less disabled patients. However, an increase of 10°C prolonged the T25FW by just 0.4 s. Other outcomes were not associated with ambient temperatures. Higher ambient temperature might compromise walking capabilities in patients with MS with a manifest walking impairment. However, effects are small and not detectable in mildly disabled patients. Hand function, cognition, mood and fatigue do not appear to be correlated with ambient temperature. © 2017 EAN.

  6. Coherent Uncertainty Analysis of Aerosol Measurements from Multiple Satellite Sensors

    Science.gov (United States)

    Petrenko, M.; Ichoku, C.

    2013-01-01

    Aerosol retrievals from multiple spaceborne sensors, including MODIS (on Terra and Aqua), MISR, OMI, POLDER, CALIOP, and SeaWiFS altogether, a total of 11 different aerosol products were comparatively analyzed using data collocated with ground-based aerosol observations from the Aerosol Robotic Network (AERONET) stations within the Multi-sensor Aerosol Products Sampling System (MAPSS, http://giovanni.gsfc.nasa.gov/mapss/ and http://giovanni.gsfc.nasa.gov/aerostat/). The analysis was performed by comparing quality-screened satellite aerosol optical depth or thickness (AOD or AOT) retrievals during 2006-2010 to available collocated AERONET measurements globally, regionally, and seasonally, and deriving a number of statistical measures of accuracy. We used a robust statistical approach to detect and remove possible outliers in the collocated data that can bias the results of the analysis. Overall, the proportion of outliers in each of the quality-screened AOD products was within 12%. Squared correlation coefficient (R2) values of the satellite AOD retrievals relative to AERONET exceeded 0.6, with R2 for most of the products exceeding 0.7 over land and 0.8 over ocean. Root mean square error (RMSE) values for most of the AOD products were within 0.15 over land and 0.09 over ocean. We have been able to generate global maps showing regions where the different products present advantages over the others, as well as the relative performance of each product over different landcover types. It was observed that while MODIS, MISR, and SeaWiFS provide accurate retrievals over most of the landcover types, multi-angle capabilities make MISR the only sensor to retrieve reliable AOD over barren and snow / ice surfaces. Likewise, active sensing enables CALIOP to retrieve aerosol properties over bright-surface shrublands more accurately than the other sensors, while POLDER, which is the only one of the sensors capable of measuring polarized aerosols, outperforms other sensors in

  7. 231 Using Multiple Regression Analysis in Modelling the Role of ...

    African Journals Online (AJOL)

    User

    of Internal Revenue, Tourism Bureau and hotel records. The multiple regression .... additional guest facilities such as restaurant, a swimming pool or child care and social function ... and provide good quality service to the public. Conclusion.

  8. Rasch analysis of the Multiple Sclerosis Impact Scale (MSIS-29)

    OpenAIRE

    Ramp, Melina; Khan, Fary; Misajon, Rose Anne; Pallant, Julie F

    2009-01-01

    Abstract Background Multiple Sclerosis (MS) is a degenerative neurological disease that causes impairments, including spasticity, pain, fatigue, and bladder dysfunction, which negatively impact on quality of life. The Multiple Sclerosis Impact Scale (MSIS-29) is a disease-specific health-related quality of life (HRQoL) instrument, developed using the patient's perspective on disease impact. It consists of two subscales assessing the physical (MSIS-29-PHYS) and psychological (MSIS-29-PSYCH) im...

  9. Change in quality of life and predictors of change among patients with multiple sclerosis: a prospective cohort study.

    Science.gov (United States)

    Tepavcevic, Darija Kisic; Pekmezovic, Tatjana; Stojsavljevic, Nebojsa; Kostic, Jelena; Basuroski, Irena Dujmovic; Mesaros, Sarlota; Drulovic, Jelena

    2014-04-01

    The aim of this study was to determine the changes in the health-related quality of life (HRQoL) and predictors of change among patients with multiple sclerosis (MS) at 3 and 6 years during the follow-up period. A group of 109 consecutive MS patients (McDonald's criteria) referred to the Clinic of Neurology, Belgrade, were enrolled in the study. At three time points during the study (baseline, and at 3 and 6 years during the follow-up period), the HRQoL (measured by MSQoL-54), Expanded Disability Status Scale, and Hamilton Rating Scale for Depression and Fatigue Severity Scale were assessed. During the study period, 93 patients provided both follow-up assessments. Statistically significant deterioration in the HRQoL at each subsequent time point was detected for all scales of the MSQoL-54 except for the pain and change in health scales. A higher level of education was a significant prognostic factor for a better HRQoL on the cognitive function scale throughout the entire period of observation, while marital status (single, including divorced and widowed) and increased age at the onset of MS had significant predictive values of poorer quality-of-life scores on the overall quality-of-life scale at 6-year follow-up. Higher levels of physical disability and depression at baseline were statistically significant prognostic markers for deterioration in HRQoL for the majority of MSQoL-54 scales during the entire follow-up period. Our study suggests that baseline demographic and clinical characteristics could be applied as prognostic markers of the HRQOL for patients diagnosed with MS.

  10. Using Module Analysis for Multiple Choice Responses: A New Method Applied to Force Concept Inventory Data

    Science.gov (United States)

    Brewe, Eric; Bruun, Jesper; Bearden, Ian G.

    2016-01-01

    We describe "Module Analysis for Multiple Choice Responses" (MAMCR), a new methodology for carrying out network analysis on responses to multiple choice assessments. This method is used to identify modules of non-normative responses which can then be interpreted as an alternative to factor analysis. MAMCR allows us to identify conceptual…

  11. Fruits and vegetables consumption and risk of stroke: a meta-analysis of prospective cohort studies.

    Science.gov (United States)

    Hu, Dan; Huang, Junqian; Wang, Yuchun; Zhang, Dongfeng; Qu, Yan

    2014-06-01

    We conducted a meta-analysis to summarize evidence from prospective cohort studies about the association of fruits and vegetables consumption with the risk of stroke. Pertinent studies were identified by a search of Embase and PubMed databases to January 2014. Study-specific relative risks with 95% confidence intervals were pooled using a random-effects model. Dose-response relationship was assessed by restricted cubic spline. Twenty prospective cohort studies were included, involving 16 981 stroke events among 760 629 participants. The multivariable relative risk (95% confidence intervals) of stroke for the highest versus lowest category of total fruits and vegetables consumption was 0.79 (0.75-0.84), and the effect was 0.77 (0.71-0.84) for fruits consumption and 0.86 (0.79-0.93) for vegetables consumption. Subgroup and meta-regression showed that the inverse association of total fruits and vegetables consumption with the risk of stroke was consistent in subgroup analysis. Citrus fruits, apples/pears, and leafy vegetables might contribute to the protection. The linear dose-response relationship showed that the risk of stroke decreased by 32% (0.68 [0.56-0.82]) and 11% (0.89 [0.81-0.98]) for every 200 g per day increment in fruits consumption (P for nonlinearity=0.77) and vegetables consumption (P for nonlinearity=0.62), respectively. Fruits and vegetables consumption are inversely associated with the risk of stroke. © 2014 American Heart Association, Inc.

  12. Discovering Cohorts of Pregnant Women From Social Media for Safety Surveillance and Analysis.

    Science.gov (United States)

    Sarker, Abeed; Chandrashekar, Pramod; Magge, Arjun; Cai, Haitao; Klein, Ari; Gonzalez, Graciela

    2017-10-30

    , the implemented classifier obtained an overall F 1 score of 0.84 (0.88 for the pregnancy class and 0.68 for the nonpregnancy class). Precision for the pregnancy class was 0.93, and recall was 0.84. Feature analysis showed that the combination of dense and sparse vectors for classification achieved optimal performance. Employing the trained classifier resulted in the identification of 71,954 users from the collected posts. Over 250 million posts were retrieved for these users, which provided a multitude of longitudinal information about them. Social media sources such as Twitter can be used to identify large cohorts of pregnant women and to gather longitudinal information via automated processing of their postings. Considering the many drawbacks and limitations of pregnancy registries, social media mining may provide beneficial complementary information. Although the cohort sizes identified over social media are large, future research will have to assess the completeness of the information available through them. ©Abeed Sarker, Pramod Chandrashekar, Arjun Magge, Haitao Cai, Ari Klein, Graciela Gonzalez. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 30.10.2017.

  13. Performance analysis of commercial multiple-input-multiple-output access point in distributed antenna system.

    Science.gov (United States)

    Fan, Yuting; Aighobahi, Anthony E; Gomes, Nathan J; Xu, Kun; Li, Jianqiang

    2015-03-23

    In this paper, we experimentally investigate the throughput of IEEE 802.11n 2x2 multiple-input-multiple-output (MIMO) signals in a radio-over-fiber-based distributed antenna system (DAS) with different fiber lengths and power imbalance. Both a MIMO-supported access point (AP) and a spatial-diversity-supported AP were separately employed in the experiments. Throughput measurements were carried out with wireless users at different locations in a typical office environment. For the different fiber length effect, the results indicate that MIMO signals can maintain high throughput when the fiber length difference between the two remote antenna units (RAUs) is under 100 m and falls quickly when the length difference is greater. For the spatial diversity signals, high throughput can be maintained even when the difference is 150 m. On the other hand, the separation of the MIMO antennas allows additional freedom in placing the antennas in strategic locations for overall improved system performance, although it may also lead to received power imbalance problems. The results show that the throughput performance drops in specific positions when the received power imbalance is above around 13 dB. Hence, there is a trade-off between the extent of the wireless coverage for moderate bit-rates and the area over which peak bit-rates can be achieved.

  14. The feasibility of collecting information from people with Multiple Sclerosis for the UK MS Register via a web portal: characterising a cohort of people with MS

    Directory of Open Access Journals (Sweden)

    Ford David V

    2012-07-01

    Full Text Available Abstract Background A UK Register of people with Multiple Sclerosis has been developed to address the need for an increased knowledge-base about MS. The Register is being populated via: a web-based portal; NHS neurology clinical systems; and administrative data sources. The data are de-identified and linked at the individual level. At the outset, it was not known whether people with MS would wish to participate in the UK MS Register by personally contributing their data to the Register via a web-based system. Therefore, the research aim of this work was to build an internet-mounted recruitment and consenting technology for people with Multiple Sclerosis, and to assess its feasibility as a questionnaire delivery platform to contribute data to the UK MS Register, by determining whether the information provided could be used to describe a cohort of people with MS. Methods The web portal was developed using VB.net and JQuery with a Microsoft SQL 2008 database. UK adults with MS can self-register and enter data about themselves by completing validated questionnaires. Descriptive statistics were used to characterise the respondents. Results The web portal was launched in May 2011, and in first three months 7,279 individuals registered on the portal. The ratio of men to women was 1:2.4 (n = 5,899, the mean self-reported age at first symptoms was 33.8 (SD 10.5 years, and at diagnosis 39.6 (SD 10.3 years (n = 4,401. The reported types of MS were: 15% primary progressive, 63% relapsing-remitting, 8% secondary progressive, and 14% unknown (n = 5,400. These characteristics are similar to those of the prevalent MS population. Employment rates, sickness/disability rates, ethnicity and educational qualifications were compared with the general UK population. Information about the respondents’ experience of early symptoms and the process of diagnosis, plus living arrangements are also reported. Conclusions These initial findings from the MS

  15. Unstart coupling mechanism analysis of multiple-modules hypersonic inlet.

    Science.gov (United States)

    Hu, Jichao; Chang, Juntao; Wang, Lei; Cao, Shibin; Bao, Wen

    2013-01-01

    The combination of multiplemodules in parallel manner is an important way to achieve the much higher thrust of scramjet engine. For the multiple-modules scramjet engine, when inlet unstarted oscillatory flow appears in a single-module engine due to high backpressure, how to interact with each module by massflow spillage, and whether inlet unstart occurs in other modules are important issues. The unstarted flowfield and coupling characteristic for a three-module hypersonic inlet caused by center module II and side module III were, conducted respectively. The results indicate that the other two hypersonic inlets are forced into unstarted flow when unstarted phenomenon appears on a single-module hypersonic inlet due to high backpressure, and the reversed flow in the isolator dominates the formation, expansion, shrinkage, and disappearance of the vortexes, and thus, it is the major factor of unstart coupling of multiple-modules hypersonic inlet. The coupling effect among multiple modules makes hypersonic inlet be more likely unstarted.

  16. Cancer Incidence in Patients with Acromegaly: A cohort study and meta-analysis of the literature

    DEFF Research Database (Denmark)

    Dal, Jakob; Leisner, Michelle Z; Hermansen, Kasper

    2018-01-01

    -2010) including 529 acromegaly cases was performed. Incident cancer diagnoses and mortality were compared to national rates estimating standardized incidence ratios (SIRs). A meta-analysis of cancer SIRs from 23 studies (including the present one) was performed. Results: The cohort study identified 81 cases...... in acromegaly (SIR 1.3 [95% CI: 1.1-1.6]), cancer-specific mortality was not. The meta-analysis yielded a SIR of overall cancer of 1.5 [95% CI: 1.2-1.8]. SIRs were elevated for colorectal cancer: 2.6 [95% CI: 1.7-4.0], thyroid cancer: 9.2 [95% CI: 4.2-19.9], breast cancer: 1.6 [1.1-2.3], gastric cancer: 2.0 [95......% CI: 1.4-2.9], and urinary tract cancer: 1.5 [95% CI: 1.0-2.3]). In general, cancer SIR was higher in single-center studies and in studies with meta-analysis...

  17. Harmonization of Food-Frequency Questionnaires and Dietary Pattern Analysis in 4 Ethnically Diverse Birth Cohorts.

    Science.gov (United States)

    de Souza, Russell J; Zulyniak, Michael A; Desai, Dipika; Shaikh, Mateen R; Campbell, Natalie C; Lefebvre, Diana L; Gupta, Milan; Wilson, Julie; Wahi, Gita; Atkinson, Stephanie A; Teo, Koon K; Subbarao, Padmaja; Becker, Allan B; Mandhane, Piushkumar J; Turvey, Stuart E; Sears, Malcolm R; Anand, Sonia S

    2016-11-01

    Canada is an ethnically diverse nation, which introduces challenges for health care providers tasked with providing evidence-based dietary advice. We aimed to harmonize food-frequency questionnaires (FFQs) across 4 birth cohorts of ethnically diverse pregnant women to derive robust dietary patterns to investigate maternal and newborn outcomes. The NutriGen Alliance comprises 4 prospective birth cohorts and includes 4880 Canadian mother-infant pairs of predominantly white European [CHILD (Canadian Healthy Infant Longitudinal Development) and FAMILY (Family Atherosclerosis Monitoring In earLY life)], South Asian [START (SouTh Asian birth cohoRT)-Canada], or Aboriginal [ABC (Aboriginal Birth Cohort)] origins. CHILD used a multiethnic FFQ based on a previously validated instrument designed by the Fred Hutchinson Cancer Research Center, whereas FAMILY, START, and ABC used questionnaires specifically designed for use in white European, South Asian, and Aboriginal people, respectively. The serving sizes and consumption frequencies of individual food items within the 4 FFQs were harmonized and aggregated into 36 common food groups. Principal components analysis was used to identify dietary patterns that were internally validated against self-reported vegetarian status and externally validated against a modified Alternative Healthy Eating Index (mAHEI). Three maternal dietary patterns were identified-"plant-based," "Western," and "health-conscious"-which collectively explained 29% of the total variability in eating habits observed in the NutriGen Alliance. These patterns were strongly associated with self-reported vegetarian status (OR: 3.85; 95% CI: 3.47, 4.29; r 2 = 0.30, P < 0.001; for a plant-based diet), and average adherence to the plant-based diet was higher in participants in the fourth quartile of the mAHEI than in the first quartile (mean difference: 46.1%; r 2 = 0.81, P < 0.001). Dietary data collected by using FFQs from ethnically diverse pregnant women can be

  18. Perturbative analysis of multiple-field cosmological inflation

    International Nuclear Information System (INIS)

    Lahiri, Joydev; Bhattacharya, Gautam

    2006-01-01

    We develop a general formalism for analyzing linear perturbations in multiple-field cosmological inflation based on the gauge-ready approach. Our inflationary model consists of an arbitrary number of scalar fields with non-minimal kinetic terms. We solve the equations for scalar- and tensor-type perturbations during inflation to the first order in slow roll, and then obtain the super-horizon solutions for adiabatic and isocurvature perturbations after inflation. Analytic expressions for power-spectra and spectral indices arising from multiple-field inflation are presented

  19. Flutter analysis of an airfoil with multiple nonlinearities and uncertainties

    Directory of Open Access Journals (Sweden)

    Haitao Liao

    2013-09-01

    Full Text Available An original method for calculating the limit cycle oscillations of nonlinear aero-elastic system is presented. The problem of determining the maximum vibration amplitude of limit cycle is transformed into a nonlinear optimization problem. The harmonic balance method and the Floquet theory are selected to construct the general nonlinear equality and inequality constraints. The resulting constrained maximization problem is then solved by using the MultiStart algorithm. Finally, the proposed approach is validated and used to analyse the limit cycle oscillations of an airfoil with multiple nonlinearities and uncertainties. Numerical examples show that the coexistence of multiple nonlinearities may lead to low amplitude limit cycle oscillation.

  20. Evaluation of Clinical Gait Analysis parameters in patients affected by Multiple Sclerosis: Analysis of kinematics.

    Science.gov (United States)

    Severini, Giacomo; Manca, Mario; Ferraresi, Giovanni; Caniatti, Luisa Maria; Cosma, Michela; Baldasso, Francesco; Straudi, Sofia; Morelli, Monica; Basaglia, Nino

    2017-06-01

    Clinical Gait Analysis is commonly used to evaluate specific gait characteristics of patients affected by Multiple Sclerosis. The aim of this report is to present a retrospective cross-sectional analysis of the changes in Clinical Gait Analysis parameters in patients affected by Multiple Sclerosis. In this study a sample of 51 patients with different levels of disability (Expanded Disability Status Scale 2-6.5) was analyzed. We extracted a set of 52 parameters from the Clinical Gait Analysis of each patient and used statistical analysis and linear regression to assess differences among several groups of subjects stratified according to the Expanded Disability Status Scale and 6-Minutes Walking Test. The impact of assistive devices (e.g. canes and crutches) on the kinematics was also assessed in a subsample of patients. Subjects showed decreased range of motion at hip, knee and ankle that translated in increased pelvic tilt and hiking. Comparison between the two stratifications showed that gait speed during 6-Minutes Walking Test is better at discriminating patients' kinematics with respect to Expanded Disability Status Scale. Assistive devices were shown not to significantly impact gait kinematics and the Clinical Gait Analysis parameters analyzed. We were able to characterize disability-related trends in gait kinematics. The results presented in this report provide a small atlas of the changes in gait characteristics associated with different disability levels in the Multiple Sclerosis population. This information could be used to effectively track the progression of MS and the effect of different therapies. Copyright © 2017. Published by Elsevier Ltd.

  1. Combining Spot Sign and Intracerebral Hemorrhage Score to Estimate Functional Outcome: Analysis From the PREDICT Cohort.

    Science.gov (United States)

    Schneider, Hauke; Huynh, Thien J; Demchuk, Andrew M; Dowlatshahi, Dar; Rodriguez-Luna, David; Silva, Yolanda; Aviv, Richard; Dzialowski, Imanuel

    2018-06-01

    The intracerebral hemorrhage (ICH) score is the most commonly used grading scale for stratifying functional outcome in patients with acute ICH. We sought to determine whether a combination of the ICH score and the computed tomographic angiography spot sign may improve outcome prediction in the cohort of a prospective multicenter hemorrhage trial. Prospectively collected data from 241 patients from the observational PREDICT study (Prediction of Hematoma Growth and Outcome in Patients With Intracerebral Hemorrhage Using the CT-Angiography Spot Sign) were analyzed. Functional outcome at 3 months was dichotomized using the modified Rankin Scale (0-3 versus 4-6). Performance of (1) the ICH score and (2) the spot sign ICH score-a scoring scale combining ICH score and spot sign number-was tested. Multivariable analysis demonstrated that ICH score (odds ratio, 3.2; 95% confidence interval, 2.2-4.8) and spot sign number (n=1: odds ratio, 2.7; 95% confidence interval, 1.1-7.4; n>1: odds ratio, 3.8; 95% confidence interval, 1.2-17.1) were independently predictive of functional outcome at 3 months with similar odds ratios. Prediction of functional outcome was not significantly different using the spot sign ICH score compared with the ICH score alone (spot sign ICH score area under curve versus ICH score area under curve: P =0.14). In the PREDICT cohort, a prognostic score adding the computed tomographic angiography-based spot sign to the established ICH score did not improve functional outcome prediction compared with the ICH score. © 2018 American Heart Association, Inc.

  2. Coffee consumption and risk of cancers: a meta-analysis of cohort studies

    Directory of Open Access Journals (Sweden)

    Zou Jian

    2011-03-01

    Full Text Available Abstract Background Coffee consumption has been shown to be associated with cancer of various sites in epidemiological studies. However, there is no comprehensive overview of the substantial body of epidemiologic evidence. Methods We searched MEDLINE, EMBASE, Science Citation Index Expanded and bibliographies of retrieved articles. Prospective cohort studies were included if they reported relative risks (RRs and corresponding 95% confidence intervals (CIs of various cancers with respect to frequency of coffee intake. We did random-effects meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of cancer associated with 1 cup/day increment of coffee consumption. Results 59 studies, consisting of 40 independent cohorts, met the inclusion criteria. Compared with individuals who did not or seldom drink coffee per day, the pooled RR of cancer was 0.87 (95% CI, 0.82-0.92 for regular coffee drinkers, 0.89 (0.84-0.93 for low to moderate coffee drinkers, and 0.82 (0.74-0.89 for high drinkers. Overall, an increase in consumption of 1 cup of coffee per day was associated with a 3% reduced risk of cancers (RR, 0.97; 95% CI, 0.96-0.98. In subgroup analyses, we noted that, coffee drinking was associated with a reduced risk of bladder, breast, buccal and pharyngeal, colorectal, endometrial, esophageal, hepatocellular, leukemic, pancreatic, and prostate cancers. Conclusions Findings from this meta-analysis suggest that coffee consumption may reduce the total cancer incidence and it also has an inverse association with some type of cancers.

  3. Socioeconomic conditions across life related to multiple measures of the endocrine system in older adults: Longitudinal findings from a British birth cohort study.

    Science.gov (United States)

    Bann, David; Hardy, Rebecca; Cooper, Rachel; Lashen, Hany; Keevil, Brian; Wu, Frederick C W; Holly, Jeff M P; Ong, Ken K; Ben-Shlomo, Yoav; Kuh, Diana

    2015-12-01

    Little is known about how socioeconomic position (SEP) across life impacts on different axes of the endocrine system which are thought to underlie the ageing process and its adverse consequences. We examined how indicators of SEP across life related to multiple markers of the endocrine system in late midlife, and hypothesized that lower SEP across life would be associated with an adverse hormone profile across multiple axes. Data were from a British cohort study of 875 men and 905 women followed since their birth in March 1946 with circulating free testosterone and insulin-like growth factor-I (IGF-I) measured at both 53 and 60-64 years, and evening cortisol at 60-64 years. Indicators of SEP were ascertained prospectively across life-paternal occupational class at 4, highest educational attainment at 26, household occupational class at 53, and household income at 60-64 years. Associations between SEP and hormones were investigated using multiple regression and logistic regression models. Lower SEP was associated with lower free testosterone among men, higher free testosterone among women, and lower IGF-I and higher evening cortisol in both sexes. For example, the mean standardised difference in IGF-I comparing the lowest with the highest educational attainment at 26 years (slope index of inequality) was -0.4 in men (95% CI -0.7 to -0.2) and -0.4 in women (-0.6 to -0.2). Associations with each hormone differed by SEP indicator used and sex, and were particularly pronounced when using a composite adverse hormone score. For example, the odds of having 1 additional adverse hormone concentration in the lowest compared with highest education level were 3.7 (95% CI: 2.1, 6.3) among men, and 1.6 (1.0, 2.7) among women (P (sex interaction) = 0.02). We found no evidence that SEP was related to apparent age-related declines in free testosterone or IGF-I. Lower SEP was associated with an adverse hormone profile across multiple endocrine axes. SEP differences in endocrine

  4. Statistical Analysis of Questionnaire on Physical Rehabilitation in Multiple Sclerosis

    Czech Academy of Sciences Publication Activity Database

    Martinková, Patrícia; Řasová, K.

    -, č. 3 (2010), S340 ISSN 1210-7859. [Obnovené neuroimunologickjé a likvorologické dny. 21.05.2010-22.05.2010, Praha] R&D Projects: GA MŠk(CZ) 1M06014 Institutional research plan: CEZ:AV0Z10300504 Keywords : questionnaire * physical rehabilitation * multiple sclerosis Subject RIV: IN - Informatics, Computer Science

  5. Multiple Intelligences Theory and Iranian Textbooks: An Analysis

    Science.gov (United States)

    Taase, Yoones

    2012-01-01

    The purpose of this study is to investigate locally designed ELT textbooks in the light of multiple intelligences theory. Three textbooks (grade 1.2.3) used in guidance school of Iranian educational system were analyzed using MI checklist developed by Botelho, Mario do Rozarioand. Catered for kinds of intelligences in the activities and exercises…

  6. Failure analysis of multiple delaminated composite plates due to ...

    Indian Academy of Sciences (India)

    Unknown

    plates are assumed to contain both single and multiple delaminations. For the case of impact, ... delamination on the first ply failure of the laminate is scarce. ..... 1 in the bottom layer, it was of the opposite sign for the top layer. The plots for ...

  7. Multiplicative synergistic risk of hepatocellular carcinoma development among hepatitis B and C co-infected subjects in HBV endemic area: a community-based cohort study

    International Nuclear Information System (INIS)

    Oh, Jin-Kyoung; Shin, Hai-Rim; Lim, Min Kyung; Cho, Heeyoun; Kim, Dong-Il; Jee, Youngmee; Yun, Haesun; Yoo, Keun-Young

    2012-01-01

    There has been limited study on the effect of infection with different hepatitis C virus (HCV) genotypes on the risk of hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) endemic regions of Asia. Hazard ratios of HCC development were estimated for HBV and HCV co-infected subjects among a community-based prospective cohort. HCV genotype was determined in HCV RNA-positive samples. Incident HCC cases were identified through linkage to the cancer registry. HCC incidence was 79 per 100,000 person-years in the study population (50 incident cases among 6,694 individuals within 63,170 person-years with an average of 9.4 years of follow-up); seroprevalence of HBsAg and anti-HCV was 5.2% and 5.6%. Adjusted hazard ratios of HCC by HBsAg positivity and anti-HCV positivity were 13.3 (CI: 7.3-24.4) and 6.7 (CI: 3.6-12.6). HRs of HBV and HCV monoinfection, and HBV/HCV coinfection were 17.1 (CI: 8.4-34.8), 10.4 (CI: 4.9-22.1) and 115.0 (CI: 32.5-407.3). Multiplicative synergistic effect of HBV/HCV coinfection on HCC risk was also observed (synergy index: 4.5, CI: 1.3-15.5). Infection with HCV genotype 1 (HR: 29.7, CI: 13.6-46.8) and mixed infection with genotype 1 and 2 (HR: 68.7, CI: 16.4-288.4) significantly elevated HCC risk, much higher than HBV infection. The effect of differences in HCV genotype and the multiplicative synergistic effect of HBV/HCV coinfection on HCC risk shown in the present study underline the need for comprehensive identification of hepatitis infection status in order to prevent and control HCC in this HBV endemic area

  8. Decreasing rate of multiple treatment modifications among individuals who initiated antiretroviral therapy in 1997-2009 in the Danish HIV Cohort Study

    DEFF Research Database (Denmark)

    Helleberg, Marie; Kronborg, Gitte; Larsen, Carsten S

    2012-01-01

    BACKGROUND: We hypothesized that rates and reasons for treatment modifications have changed since the implementation of combination antiretroviral therapy (cART) due to improvements in therapy. METHODS: From a nationwide population-based cohort study we identified all HIV-1 infected adults who...... initiated cART in Denmark 1997-2009 and were followed (3)1 year. Incidence rate ratios (IRR) and reasons for treatment modifications were estimated and compared between patients, who initiated treatment in 1997-1999, 2000-2004 and 2005-2009. Rates of discontinuation of individual antiretroviral drugs (ARVs......) were evaluated. RESULTS: 3,107 patients were followed median 7.3 years (IQR 3.8-10.8). Rates of first treatment modification ≤1 year after cART initiation did not change (IRR 0.88 (95% CI 0.78-1.01) and 1.03 (95% CI 0.90-1.18) in 2000-2004 and 2005-2009 compared to 1997-1999). Rates of multiple...

  9. A nested case-control study of influenza vaccination was a cost-effective alternative to a full cohort analysis

    NARCIS (Netherlands)

    Hak, E; Wei, F; Grobbee, D E; Nichol, K L

    OBJECTIVE: In the absence of trial results that are applicable to the target population, nested case-control studies might be an alternative to full-cohort analysis. We compared relative and absolute estimates of associations in an influenza vaccine study using both designs. STUDY DESIGN AND

  10. Genome-wide analysis of multi-ancestry cohorts identifies new loci influencing intraocular pressure and susceptibility to glaucoma

    NARCIS (Netherlands)

    Hysi, Pirro G.; Cheng, Ching-Yu; Springelkamp, Henriet; Macgregor, Stuart; Bailey, Jessica N. Cooke; Wojciechowski, Robert; Vitart, Veronique; Nag, Abhishek; Hewitt, Alex W.; Hohn, Rene; Venturini, Cristina; Mirshahi, Alireza; Ramdas, Wishal D.; Thorleifsson, Gudmar; Vithana, Eranga; Khor, Chiea-Chuen; Stefansson, Arni B.; Liao, Jiemin; Haines, Jonathan L.; Amin, Najaf; Wang, Ya Xing; Wild, Philipp S.; Ozel, Ayse B.; Li, Jun Z.; Fleck, Brian W.; Zeller, Tanja; Staffieri, Sandra E.; Teo, Yik-Ying; Cuellar-Partida, Gabriel; Luo, Xiaoyan; Allingham, R. Rand; Richards, Julia E.; Senft, Andrea; Karssen, Lennart C.; Zheng, Yingfeng; Bellenguez, Celine; Xu, Liang; Iglesias, Adriana I.; Wilson, James F.; Kang, Jae H.; van Leeuwen, Elisabeth M.; Jonsson, Vesteinn; Thorsteinsdottir, Unnur; Despriet, Dominiek D. G.; Ennis, Sarah; Moroi, Sayoko E.; Martin, Nicholas G.; Jansonius, Nomdo M.; Yazar, Seyhan; Tai, E-Shyong

    2014-01-01

    Elevated intraocular pressure (IOP) is an important risk factor in developing glaucoma, and variability in IOP might herald glaucomatous development or progression. We report the results of a genome-wide association study meta-analysis of 18 population cohorts from the International Glaucoma

  11. Congenital lumbar spinal stenosis: a prospective, control-matched, cohort radiographic analysis.

    Science.gov (United States)

    Singh, Kern; Samartzis, Dino; Vaccaro, Alexander R; Nassr, Ahmad; Andersson, Gunnar B; Yoon, S Tim; Phillips, Frank M; Goldberg, Edward J; An, Howard S

    2005-01-01

    Degenerative lumbar spinal stenosis manifests primarily after the sixth decade of life as a result of facet hypertrophy and degenerative disc disease. Congenital stenosis, on the other hand, presents earlier in age with similar clinical findings but with multilevel involvement and fewer degenerative changes. These patients may have subtle anatomic variations of the lumbar spine that may increase the likelihood of thecal sac compression. However, to the authors' knowledge, no quantitative studies have addressed various radiographic parameters of symptomatic, congenitally stenotic individuals to normal subjects. To radiographically quantify and compare the anatomy of the lumbar spine in symptomatic, congenitally stenotic individuals to age- and sex-matched, asymptomatic, nonstenotic controlled individuals. A prospective, control-matched, cohort radiographic analysis. Axial and sagittal magnetic resonance imaging (MRI) and lateral, lumbar, plain radiographs of 20 surgically treated patients who were given a clinical diagnosis of congenital lumbar stenosis by the senior author were randomized with images of 20, asymptomatic age- and sex-matched subjects. MRIs and lateral, lumbar, plain radiographs were independently quantitatively assessed by two individuals. Measurements obtained from the axial MRIs included: midline anterior-posterior (AP) vertebral body diameter, vertebral body width, midline AP canal diameter, canal width, spinal canal cross-sectional area, pedicle length, and pedicle width. From the sagittal MRIs, the following measurements were calculated: AP vertebral body diameter, vertebral body height, and AP canal diameter at the mid-vertebral level. On the lateral, lumbar, plain radiograph (L3 level), the AP diameters of the vertebral body spinal canal were measured. The images of these 40 individuals were then randomized and distributed in a blinded fashion to five separate spine surgeons who graded the presence and severity of congenital stenosis

  12. Coffee drinking and pancreatic cancer risk: a meta-analysis of cohort studies.

    Science.gov (United States)

    Dong, Jie; Zou, Jian; Yu, Xiao-Feng

    2011-03-07

    To quantitatively assess the relationship between coffee consumption and incidence of pancreatic cancer in a meta-analysis of cohort studies. We searched MEDLINE, EMBASE, Science Citation Index Expanded and bibliographies of retrieved articles. Studies were included if they reported relative risks (RRs) and corresponding 95% CIs of pancreatic cancer with respect to frequency of coffee intake. We performed random-effects meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of pancreatic cancer associated with a 1 cup/d increment in coffee consumption. Fourteen studies met the inclusion criteria, which included 671,080 individuals (1496 cancer events) with an average follow-up of 14.9 years. Compared with individuals who did not drink or seldom drank coffee per day, the pooled RR of pancreatic cancer was 0.82 (95% CI: 0.69-0.95) for regular coffee drinkers, 0.86 (0.76-0.96) for low to moderate coffee drinkers, and 0.68 (0.51-0.84) for high drinkers. In subgroup analyses, we noted that, coffee drinking was associated with a reduced risk of pancreatic cancer in men, while this association was not seen in women. These associations were also similar in studies from North America, Europe, and the Asia-Pacific region. Findings from this meta-analysis suggest that there is an inverse relationship between coffee drinking and risk of pancreatic cancer.

  13. Fish intake and risk of heart failure: A meta-analysis of five prospective cohort studies

    Science.gov (United States)

    HOU, LI-NA; LI, FEI; ZHOU, YOU; NIE, SHI-HUAI; SU, LIANG; CHEN, PING-AN; TAN, WAN-LONG; XU, DING-LI

    2012-01-01

    The findings on the association between fish intake and the risk of heart failure (HF) have been inconsistent. The purpose of this study was to clarify this potential association. We searched for relevant studies in the PubMed database through January 2012 and manually reviewed references. Five independent prospective cohort studies involving 5,273 cases and 144,917 participants were included. The summary relative risk estimates (SRRE) based on the highest compared with the lowest category of fish consumption were estimated by variance-based meta-analysis. In addition, we performed sensitivity and dose-response analyses to examine the association. Overall, an absence of an association between fish intake and HF was observed (SRRE=1.00; 95% CI, 0.81–1.24). However, fried fish intake positively associated with HF (SRRE=1.40; 95% CI, 1.22–1.61). In addition, dose-response analysis of fried fish suggested that each increment of six fried fish per month corresponded to a 37% increase of HF rate (RR=1.37; 95% CI, 1.20–1.56). In conclusion, our findings suggest that there is no significant association between fish intake and risk of HF, with the exception of a possible positive correlation with individuals comsuming fried fish, based on a limited number of studies. Future studies are required to confirm these findings. PMID:23181122

  14. Multiple-Group Analysis Using the sem Package in the R System

    Science.gov (United States)

    Evermann, Joerg

    2010-01-01

    Multiple-group analysis in covariance-based structural equation modeling (SEM) is an important technique to ensure the invariance of latent construct measurements and the validity of theoretical models across different subpopulations. However, not all SEM software packages provide multiple-group analysis capabilities. The sem package for the R…

  15. Multiple regression for physiological data analysis: the problem of multicollinearity.

    Science.gov (United States)

    Slinker, B K; Glantz, S A

    1985-07-01

    Multiple linear regression, in which several predictor variables are related to a response variable, is a powerful statistical tool for gaining quantitative insight into complex in vivo physiological systems. For these insights to be correct, all predictor variables must be uncorrelated. However, in many physiological experiments the predictor variables cannot be precisely controlled and thus change in parallel (i.e., they are highly correlated). There is a redundancy of information about the response, a situation called multicollinearity, that leads to numerical problems in estimating the parameters in regression equations; the parameters are often of incorrect magnitude or sign or have large standard errors. Although multicollinearity can be avoided with good experimental design, not all interesting physiological questions can be studied without encountering multicollinearity. In these cases various ad hoc procedures have been proposed to mitigate multicollinearity. Although many of these procedures are controversial, they can be helpful in applying multiple linear regression to some physiological problems.

  16. Reliability Analysis Multiple Redundancy Controller for Nuclear Safety Systems

    International Nuclear Information System (INIS)

    Son, Gwangseop; Kim, Donghoon; Son, Choulwoong

    2013-01-01

    This controller is configured for multiple modular redundancy (MMR) composed of dual modular redundancy (DMR) and triple modular redundancy (TMR). The architecture of MRC is briefly described, and the Markov model is developed. Based on the model, the reliability and Mean Time To Failure (MTTF) are analyzed. In this paper, the architecture of MRC for nuclear safety systems is described. The MRC is configured for multiple modular redundancy (MMR) composed of dual modular redundancy (DMR) and triple modular redundancy (TMR). Markov models for MRC architecture was developed, and then the reliability was analyzed by using the model. From the reliability analyses for the MRC, it is obtained that the failure rate of each module in the MRC should be less than 2 Χ 10 -4 /hour and the MTTF average increase rate depending on FCF increment, i. e. ΔMTTF/ΔFCF, is 4 months/0.1

  17. Radiography and bone scintigraphy in multiple myeloma: a comparative analysis

    International Nuclear Information System (INIS)

    Ludwig, H.; Kumpan, W.; Sinzinger, H.

    1982-01-01

    The sensitivity of radionuclide imaging for detecting skeletal lesions was compared with that of radiography by evaluating 573 different anatomical sites in 41 patients with multiple myeloma. Radiography revealed a significantly greater number of myeloma-related bone lesions than did radionuclide imaging. Of the 179 myeloma-related bone lesions detected when both techniques were applied, 163 were seen by radiography and 82 by radionuclide imaging. Ninety-seven lesions were detected by radiography alone and 16 lesions seen by scintiscanning only, yielding a sensitivity of 91% for the former and of 46% for the latter technique. Radionuclide imaging proved superior to radiography only occasionally in the rib cage, and rarely in other anatomical sites. These findings suggest that radiography is the method of first choice in obtaining a skeletal survey in patients with multiple myeloma. In cases with continued pain, unexplained by standard radiography, the skeletal survey should be supplemented by tomography and radionuclide imaging. (author)

  18. Breast implants and the risk of breast cancer: a meta-analysis of cohort studies.

    Science.gov (United States)

    Noels, Eline C; Lapid, Oren; Lindeman, Jan H N; Bastiaannet, Esther

    2015-01-01

    The popularity of cosmetic breast augmentation and the incidence of breast cancer have been increasing worldwide. It has been hypothesized that the risk of breast cancer may be greater among patients who have undergone cosmetic breast implantation. The authors performed a meta-analysis of the available literature on the risk of breast cancer among women with cosmetic breast implants. The study was designed as a meta-analysis of observational studies. A systematic search of the English literature (published by August 28, 2013) was conducted in PubMed and EMBASE. Eligible reports were those that included relative risk (RR; the increased or decreased risk of breast cancer associated with breast implants) or the standardized incidence ratio (SIR) of the observed number of cases of breast cancer to the expected number of cases among patients that previously underwent cosmetic breast augmentation. Seventeen studies representing 7 cohorts were selected. Some of these were follow-up reports of previously published studies; in such cases, only the most recent reports were included in the meta-analysis. Summary SIR and RR rates and the corresponding 95% confidence intervals (CIs) were calculated with a random-effects (SIR) or fixed-effects (RR) model. The overall SIR estimate was 0.69 (95% CI, 0.56-0.85), and the overall RR, based on 4 studies, was 0.63 (95% CI, 0.56-0.71). Finding of this meta-analysis suggest that women who have undergone cosmetic breast implantation do not have an increased risk of breast cancer. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  19. Nonparametric Analysis of Right Censored Data with Multiple Comparisons

    OpenAIRE

    Shih, Hwei-Weng

    1982-01-01

    This report demonstrates the use of a computer program written in FORTRAN for the Burroughs B6800 computer at Utah State University to perform Breslow's (1970) generalization of the Kruskal-Wallis test for right censored data. A pairwise multiple comparison procedure using Bonferroni's inequality is also introduced and demonstrated. Comparisons are also made with a parametric F test and the original Kruskal-Wallis test. Application of these techniques to two data sets indicate that there is l...

  20. Analysis of a production/inventory system with multiple retailers

    OpenAIRE

    Noblesse, Ann; Boute, Robert; Lambrecht, Marc; Van Houdt, B.

    2014-01-01

    We study a production/inventory system with one manufacturing plant and multiple retailers. Production lead times at the plant are stochastic and endogenously determined by the orders placed by the different retailers. Assuming stochastic (phase-type distributed) production and setup times, we make use of matrix analytic techniques to develop a queuing model that is capable to compute the distribution of the time orders spend in the production facility, depending on the retailer’s lot s...

  1. Mediation analysis with multiple versions of the mediator

    OpenAIRE

    VanderWeele, Tyler J.

    2012-01-01

    The causal inference literature has provided definitions of direct and indirect effects based on counterfactuals that generalize the approach found in the social science literature. However, these definitions presuppose well defined hypothetical interventions on the mediator. In many settings there may be multiple ways to fix the mediator to a particular value and these different hypothetical interventions may have very different implications for the outcome of interest. In this paper we cons...

  2. Unstart Coupling Mechanism Analysis of Multiple-Modules Hypersonic Inlet

    Directory of Open Access Journals (Sweden)

    Jichao Hu

    2013-01-01

    Full Text Available The combination of multiplemodules in parallel manner is an important way to achieve the much higher thrust of scramjet engine. For the multiple-modules scramjet engine, when inlet unstarted oscillatory flow appears in a single-module engine due to high backpressure, how to interact with each module by massflow spillage, and whether inlet unstart occurs in other modules are important issues. The unstarted flowfield and coupling characteristic for a three-module hypersonic inlet caused by center module II and side module III were, conducted respectively. The results indicate that the other two hypersonic inlets are forced into unstarted flow when unstarted phenomenon appears on a single-module hypersonic inlet due to high backpressure, and the reversed flow in the isolator dominates the formation, expansion, shrinkage, and disappearance of the vortexes, and thus, it is the major factor of unstart coupling of multiple-modules hypersonic inlet. The coupling effect among multiple modules makes hypersonic inlet be more likely unstarted.

  3. Regression analysis for secondary response variable in a case-cohort study.

    Science.gov (United States)

    Pan, Yinghao; Cai, Jianwen; Kim, Sangmi; Zhou, Haibo

    2017-12-29

    Case-cohort study design has been widely used for its cost-effectiveness. In any real study, there are always other important outcomes of interest beside the failure time that the original case-cohort study is based on. How to utilize the available case-cohort data to study the relationship of a secondary outcome with the primary exposure obtained through the case-cohort study is not well studied. In this article, we propose a non-parametric estimated likelihood approach for analyzing a secondary outcome in a case-cohort study. The estimation is based on maximizing a semiparametric likelihood function that is built jointly on both time-to-failure outcome and the secondary outcome. The proposed estimator is shown to be consistent, efficient, and asymptotically normal. Finite sample performance is evaluated via simulation studies. Data from the Sister Study is analyzed to illustrate our method. © 2017, The International Biometric Society.

  4. 3-D acquisition geometry analysis : Incorporating information from multiples

    NARCIS (Netherlands)

    Kumar, A.; Blacquiere, G.; Verschuur, D.J.

    2014-01-01

    Recent advances in survey design have led to conventional common-midpoint-based analysis being replaced by the subsurface-based seismic acquisition analysis and design, with the emphasis on advance techniques of illumination analysis. Amongst them are wave-equation-based seismic illumination

  5. Sociodemographic Differences Between Alcohol Use and Sickness Absence: Pooled Analysis of Four Cohort Studies.

    Science.gov (United States)

    Ervasti, Jenni; Kivimäki, Mika; Head, Jenny; Goldberg, Marcel; Airagnes, Guillaume; Pentti, Jaana; Oksanen, Tuula; Salo, Paula; Suominen, Sakari; Jokela, Markus; Vahtera, Jussi; Zins, Marie; Virtanen, Marianna

    2018-01-01

    We examined differences in sickness absence in relation to at-risk drinking and abstinence, taking into account potential changes in consumption. We used individual-participant data (n = 46,514) from four prospective cohort studies from Finland, France and the UK. Participants responded to a survey on alcohol use at two time points 4-6 years apart, and were linked to records of sickness absence for an ~6-year follow-up after the latter survey. Abstainers were those reporting no alcohol use in either survey. At-risk drinkers at T1 were labelled as 'former', at-risk drinkers at T2 as 'current' and at-risk drinkers at both times as 'consistent' at-risk drinkers. The reference group was low-risk drinkers at both times. Study-specific analyses were stratified by sex and socioeconomic status (SES) and the estimates were pooled using meta-analysis. Among men (n = 17,285), abstainers (6%), former (5%), current (5%) and consistent (7%) at-risk drinkers had an increased risk of sickness absence compared with consistent low-risk drinkers (77%). Among women (n = 29,229), only abstainers (12%) had a higher risk of sickness absence compared to consistent low-risk drinkers (74%). After adjustment for lifestyle and health, abstaining from alcohol was associated with sickness absence among people with intermediate and high SES, but not among people with low SES. The U-shaped alcohol use-sickness absence association is more consistent in men than women. Abstinence is a risk factor for sickness absence among people with higher rather than lower SES. Healthy worker effect and health selection may partly explain the observed differences. In a pooled analysis from four cohort studies from three European countries, we demonstrated a U-shaped association between alcohol use and sickness absence, particularly among men. Abstinence from alcohol was associated with increased sickness absenteeism among both sexes and across socioeconomic strata, except those with low SES. © The Author 2017

  6. The Research of Multiple Attenuation Based on Feedback Iteration and Independent Component Analysis

    Science.gov (United States)

    Xu, X.; Tong, S.; Wang, L.

    2017-12-01

    How to solve the problem of multiple suppression is a difficult problem in seismic data processing. The traditional technology for multiple attenuation is based on the principle of the minimum output energy of the seismic signal, this criterion is based on the second order statistics, and it can't achieve the multiple attenuation when the primaries and multiples are non-orthogonal. In order to solve the above problems, we combine the feedback iteration method based on the wave equation and the improved independent component analysis (ICA) based on high order statistics to suppress the multiple waves. We first use iterative feedback method to predict the free surface multiples of each order. Then, in order to predict multiples from real multiple in amplitude and phase, we design an expanded pseudo multi-channel matching filtering method to get a more accurate matching multiple result. Finally, we present the improved fast ICA algorithm which is based on the maximum non-Gauss criterion of output signal to the matching multiples and get better separation results of the primaries and the multiples. The advantage of our method is that we don't need any priori information to the prediction of the multiples, and can have a better separation result. The method has been applied to several synthetic data generated by finite-difference model technique and the Sigsbee2B model multiple data, the primaries and multiples are non-orthogonal in these models. The experiments show that after three to four iterations, we can get the perfect multiple results. Using our matching method and Fast ICA adaptive multiple subtraction, we can not only effectively preserve the effective wave energy in seismic records, but also can effectively suppress the free surface multiples, especially the multiples related to the middle and deep areas.

  7. Trends in ischemic heart disease mortality in Korea, 1985-2009: an age-period-cohort analysis.

    Science.gov (United States)

    Lee, Hye Ah; Park, Hyesook

    2012-09-01

    Economic growth and development of medical technology help to improve the average life expectancy, but the western diet and rapid conversions to poor lifestyles lead an increasing risk of major chronic diseases. Coronary heart disease mortality in Korea has been on the increase, while showing a steady decline in the other industrialized countries. An age-period-cohort analysis can help understand the trends in mortality and predict the near future. We analyzed the time trends of ischemic heart disease mortality, which is on the increase, from 1985 to 2009 using an age-period-cohort model to characterize the effects of ischemic heart disease on changes in the mortality rate over time. All three effects on total ischemic heart disease mortality were statistically significant. Regarding the period effect, the mortality rate was decreased slightly in 2000 to 2004, after it had continuously increased since the late 1980s that trend was similar in both sexes. The expected age effect was noticeable, starting from the mid-60's. In addition, the age effect in women was more remarkable than that in men. Women born from the early 1900s to 1925 observed an increase in ischemic heart mortality. That cohort effect showed significance only in women. The future cohort effect might have a lasting impact on the risk of ischemic heart disease in women with the increasing elderly population, and a national prevention policy is need to establish management of high risk by considering the age-period-cohort effect.

  8. Comparing Visual and Statistical Analysis of Multiple Baseline Design Graphs.

    Science.gov (United States)

    Wolfe, Katie; Dickenson, Tammiee S; Miller, Bridget; McGrath, Kathleen V

    2018-04-01

    A growing number of statistical analyses are being developed for single-case research. One important factor in evaluating these methods is the extent to which each corresponds to visual analysis. Few studies have compared statistical and visual analysis, and information about more recently developed statistics is scarce. Therefore, our purpose was to evaluate the agreement between visual analysis and four statistical analyses: improvement rate difference (IRD); Tau-U; Hedges, Pustejovsky, Shadish (HPS) effect size; and between-case standardized mean difference (BC-SMD). Results indicate that IRD and BC-SMD had the strongest overall agreement with visual analysis. Although Tau-U had strong agreement with visual analysis on raw values, it had poorer agreement when those values were dichotomized to represent the presence or absence of a functional relation. Overall, visual analysis appeared to be more conservative than statistical analysis, but further research is needed to evaluate the nature of these disagreements.

  9. Habitat selection and quality for multiple cohorts of young-of-the-year bluefish ( Pomatomus saltatrix): Comparisons between estuarine and ocean beaches in southern New Jersey

    Science.gov (United States)

    Taylor, David L.; Nichols, Ryan S.; Able, Kenneth W.

    2007-07-01

    In this study, seasonal and annual variability in the use of estuarine and ocean beaches by young-of-the-year bluefish, Pomatomus saltatrix, was evaluated by indices of abundance in coastal areas of southern New Jersey (1998-2000). Biological and physical factors measured at specific sites were correlated with bluefish abundance to determine the mechanisms underlying habitat selection. In addition, integrative and discrete indicators of bluefish growth were used to examine spatio-temporal dynamics in habitat quality and its effect on habitat selection by multiple cohorts of bluefish. Intra-annual recruitment to coastal areas of southern New Jersey was episodic, and resulted from the ingress of spring-spawned bluefish (hatch-date ˜April) to estuarine beaches in late May to early June, followed by the recruitment of summer-spawned fish (hatch-date ˜early July) to ocean beaches from July to October. Bluefish utilized estuarine and ocean beaches in a facultative manner that was responsive to dynamics in prey composition and temperature conditions. The recruitment and residency of bluefish in the estuary (1998-1999) and ocean beaches (1998), for example, was coincidental with the presence of the Atlantic silverside Menidia menidia and bay anchovy Anchoa mitchilli, the principal prey species for bluefish occupying these respective habitat-types. Bluefish abundance in the estuary (2000) and ocean beaches (1999-2000) was also correlated with water temperature, with the greatest catches of juveniles coinciding with their optimal growth temperature (24 °C). Bluefish growth, estimated as the slope of age-length relationships and daily specific growth rates, equaled 1.27-2.63 mm fork length (FL) d -1 and 3.8-8.7% body length increase d -1, respectively. The growth of sagittal otoliths was also used as a proxy for changes in bluefish size during and shortly before their time of capture. Accordingly, otolith growth rates of summer-spawned bluefish were greater at ocean

  10. Meta-analysis of the relationship between multiple sclerosis and migraine.

    Science.gov (United States)

    Pakpoor, Julia; Handel, Adam E; Giovannoni, Gavin; Dobson, Ruth; Ramagopalan, Sreeram V

    2012-01-01

    Studies investigating a proposed association between multiple sclerosis (MS) and migraine have produced conflicting results and a great range in the prevalence rate of migraine in MS patients. By meta-analysing all available data we aimed to establish an overall estimate of any association in order to more accurately inform clinicians and care-givers about a potential association between MS and migraine. Pubmed and EMBASE were searched to identify suitable studies. Studies were included if they were a case-control study or cohort study in which controls were not reported to have another neurological condition, were available in English, and specified migraine as a headache sub-type. The odds ratio (OR) of migraine in MS patients vs. controls was calculated using the inverse variance with random effects model in Review Manager 5.1. Eight studies were selected for inclusion, yielding a total of 1864 MS patients and 261563 control subjects. We found a significant association between migraine and MS (OR = 2.60, 95% CI 1.12-6.04), although there was significant heterogeneity. Sensitivity analysis showed that migraine without aura was associated with MS OR = 2.29 (95% CI 1.14-4.58), with no significant heterogeneity. MS patients are more than twice as likely to report migraine as controls. Care providers should be alerted to ask MS patients about migraine in order to treat it and potentially improve quality of life. Future work should further investigate the temporal relationship of this association and relationship to the clinical characteristics of MS.

  11. Meta-analysis of the relationship between multiple sclerosis and migraine.

    Directory of Open Access Journals (Sweden)

    Julia Pakpoor

    Full Text Available BACKGROUND: Studies investigating a proposed association between multiple sclerosis (MS and migraine have produced conflicting results and a great range in the prevalence rate of migraine in MS patients. By meta-analysing all available data we aimed to establish an overall estimate of any association in order to more accurately inform clinicians and care-givers about a potential association between MS and migraine. METHODS: Pubmed and EMBASE were searched to identify suitable studies. Studies were included if they were a case-control study or cohort study in which controls were not reported to have another neurological condition, were available in English, and specified migraine as a headache sub-type. The odds ratio (OR of migraine in MS patients vs. controls was calculated using the inverse variance with random effects model in Review Manager 5.1. RESULTS: Eight studies were selected for inclusion, yielding a total of 1864 MS patients and 261563 control subjects. We found a significant association between migraine and MS (OR = 2.60, 95% CI 1.12-6.04, although there was significant heterogeneity. Sensitivity analysis showed that migraine without aura was associated with MS OR = 2.29 (95% CI 1.14-4.58, with no significant heterogeneity. CONCLUSIONS: MS patients are more than twice as likely to report migraine as controls. Care providers should be alerted to ask MS patients about migraine in order to treat it and potentially improve quality of life. Future work should further investigate the temporal relationship of this association and relationship to the clinical characteristics of MS.

  12. Compressive Online Robust Principal Component Analysis with Multiple Prior Information

    DEFF Research Database (Denmark)

    Van Luong, Huynh; Deligiannis, Nikos; Seiler, Jürgen

    -rank components. Unlike conventional batch RPCA, which processes all the data directly, our method considers a small set of measurements taken per data vector (frame). Moreover, our method incorporates multiple prior information signals, namely previous reconstructed frames, to improve these paration...... and thereafter, update the prior information for the next frame. Using experiments on synthetic data, we evaluate the separation performance of the proposed algorithm. In addition, we apply the proposed algorithm to online video foreground and background separation from compressive measurements. The results show...

  13. Demographic and practice factors predicting repeated non-attendance in primary care: a national retrospective cohort analysis

    Directory of Open Access Journals (Sweden)

    David A Ellis, PhD

    2017-12-01

    Full Text Available Summary: Background: Addressing the causes of low engagement in health care is a prerequisite for reducing health inequalities. People who miss multiple appointments are an under-researched group who might have substantial unmet health needs. Individual-level patterns of missed general practice appointments might thus provide a risk marker for vulnerability and poor health outcomes. We sought to ascertain the contributions of patient and practice factors to the likelihood of missing general practice appointments. Methods: For this national retrospective cohort analysis, we extracted UK National Health Service general practice data that were routinely collected across Scotland between Sept 5, 2013, and Sept 5, 2016. We calculated the per-patient number of missed appointments from individual appointments and investigated the risk of missing a general practice appointment using a negative binomial model offset by number of appointments made. We then analysed the effect of patient-level factors (including age, sex, and socioeconomic status and practice-level factors (including appointment availability and geographical location on the risk of missing appointments. Findings: The full dataset included information from 909 073 patients, of whom 550 083 were included in the analysis after processing. We observed that 104 461 (19·0% patients missed more than two appointments in the 3 year study period. After controlling for the number of appointments made, patterns of non-attendance could be differentiated, with patients who were aged 16–30 years (relative risk ratio [RRR] 1·21, 95% CI 1·19–1·23 or older than 90 years (2·20, 2·09–2·29, and of low socioeconomic status (Scottish Index of Multiple Deprivation decile 1: RRR 2·27, 2·22–2·31 significantly more likely to miss multiple appointments. Men missed fewer appointments overall than women, but were somewhat more likely to miss appointments

  14. Global patterns and trends in stomach cancer incidence: Age, period and birth cohort analysis.

    Science.gov (United States)

    Luo, Ganfeng; Zhang, Yanting; Guo, Pi; Wang, Li; Huang, Yuanwei; Li, Ke

    2017-10-01

    The cases of stomach cancer (SC) incidence are increasing per year and the SC burden has remained very high in some countries. We aimed to evaluate the global geographical variation in SC incidence and temporal trends from 1978 to 2007, with an emphasis on the effect of birth cohort. Joinpoint regression and age-period-cohort model were applied. From 2003 to 2007, male rate were 1.5- to 3-fold higher than female in all countries. Rates were highest in Eastern Asian and South American countries. Except for Uganda, all countries showed favorable trends. Pronounced cohort-specific increases in risk for recent birth cohorts were seen in Brazil, Colombia, Iceland, New Zealand, Norway, Uganda and US white people for males and in Australia, Brazil, Colombia, Costa Rica, Czech Republic, Ecuador, Iceland, India, Malta, New Zealand, Norway, Switzerland, United Kingdom, Uganda, US black and white people for females. The cohort-specific ratio for male significantly decreased in Japan, Malta and Spain for cohorts born since 1950 and in Austria, China, Croatia, Ecuador, Russia, Switzerland and Thailand for cohorts born since 1960 and for female in Japan for cohorts born since 1950 and in Canada, China, Croatia, Latvia, Russia and Thailand for cohorts born since 1960. Disparities in incidence and carcinogenic risk persist worldwide. The favorable trends may be due to changes in environmental exposure and lifestyle, including decreased Helicobacter pylori prevalence, increased intake of fresh fruits and vegetables, the availability of refrigeration and decreased intake of salted and preserved food and smoking prevalence. © 2017 UICC.

  15. The Changing Financial Landscape of Renal Transplant Practice: A National Cohort Analysis.

    Science.gov (United States)

    Axelrod, D A; Schnitzler, M A; Xiao, H; Naik, A S; Segev, D L; Dharnidharka, V R; Brennan, D C; Lentine, K L

    2017-02-01

    Kidney transplantation has become more resource intensive as recipient complexity has increased and average donor quality has diminished over time. A national retrospective cohort study was performed to assess the impact of kidney donor and recipient characteristics on transplant center cost (exclusive of organ acquisition) and Medicare reimbursement. Data from the national transplant registry, University HealthSystem Consortium hospital costs, and Medicare payments for deceased donor (N = 53 862) and living donor (N = 36 715) transplants from 2002 to 2013 were linked and analyzed using multivariate linear regression modeling. Deceased donor kidney transplant costs were correlated with recipient (Expected Post Transplant Survival Score, degree of allosensitization, obesity, cause of renal failure), donor (age, cause of death, donation after cardiac death, terminal creatinine), and transplant (histocompatibility matching) characteristics. Living donor costs rose sharply with higher degrees of allosensitization, and were also associated with obesity, cause of renal failure, recipient work status, and 0-ABDR mismatching. Analysis of Medicare payments for a subsample of 24 809 transplants demonstrated minimal correlation with patient and donor characteristics. In conclusion, the complexity in the landscape of kidney transplantation increases center costs, posing financial disincentives that may reduce organ utilization and limit access for higher-risk populations. © Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

  16. Decisions, decisions: analysis of age, cohort, and time of testing on framing of risky decision options.

    Science.gov (United States)

    Mayhorn, Christopher B; Fisk, Arthur D; Whittle, Justin D

    2002-01-01

    Decision making in uncertain environments is a daily challenge faced by adults of all ages. Framing decision options as either gains or losses is a common method of altering decision-making behavior. In the experiment reported here, benchmark decision-making data collected in the 1970s by Tversky and Kahneman (1981, 1988) were compared with data collected from current samples of young and older adults to determine whether behavior was consistent across time. Although differences did emerge between the benchmark and the present samples, the effect of framing on decision behavior was relatively stable. The present findings suggest that adults of all ages are susceptible to framing effects. Results also indicated that apparent age differences might be better explained by an analysis of cohort and time-of-testing effects. Actual or potential applications of this research include an understanding of how framing might influence the decision-making behavior of people of all ages in a number of applied contexts, such as product warning interactions and medical decision scenarios.

  17. IMPACT OF PHYSICIAN COMMUNICATION ON DIABETIC EYE EXAMINATION ADHERENCE: Results From a Retrospective Cohort Analysis.

    Science.gov (United States)

    Storey, Philip P; Murchison, Ann P; Pizzi, Laura T; Hark, Lisa A; Dai, Yang; Leiby, Benjamin E; Haller, Julia A

    2016-01-01

    To evaluate the effect of written communication between an ophthalmologist and a primary care physician (PCP) on patient adherence to diabetic eye examination recommendations. In a retrospective cohort study of a multiethnic population at an urban ophthalmology center, records of all patients with diabetes and clinic visits between 2007 and 2010 were reviewed. Data collected included patient demographics, insurance status, hemoglobin A1C, severity of diabetic retinopathy, follow-up examinations, and written communication between a patient's ophthalmologist and PCP. Statistical analyses were performed to examine the relationship between physician communication and adherence to diabetic eye examination based on the American Academy of Ophthalmology-published recommendations. A total of 1,968 people with diabetes were included. Written communication from an ophthalmologist to a PCP was associated with increased adherence to follow-up eye examination recommendations (Odds Ratio: 1.49; 95% Confidence Interval: 1.16-1.92; P = 0.0018). Communication from a PCP to an ophthalmologist was also associated with increased adherence (Odds Ratio: 1.94; 95% Confidence Interval: 1.37-2.77; P = 0.0002). Multivariable analysis controlling for other factors associated with examination adherence confirmed that communication both to and from an ophthalmologist was independently and significantly associated with increased follow-up adherence. Patients with communication between ophthalmologists and PCPs are more likely to adhere to diabetic eye examinations.

  18. Costs of a healthy diet: analysis from the UK Women's Cohort Study.

    Science.gov (United States)

    Cade, J; Upmeier, H; Calvert, C; Greenwood, D

    1999-12-01

    To investigate the direct and indirect cost differences associated with eating a 'healthy' or 'unhealthy' diet. Analysis of data from a baseline postal questionnaire for the UK Women's Cohort Study, including a detailed food frequency questionnaire (FFQ), supplemented by a telephone interview on a sub-sample. The first 15,191 women who responded to the questionnaire, aged 35-69 years with similar numbers of meat eaters, fish eaters and vegetarians. A healthy diet indicator (hdi), with values from 0 (lowest) to 8 (highest) was developed based on the WHO dietary recommendations. Direct monetary cost of the diet was calculated using prices from the 1995 National Food Survey and the Tesco home shopping catalogue. Women in the healthy diet group were almost four times as likely to be vegetarian and have a higher educational level. For direct costs, the difference between the most extreme hdi groups was 1.48 day-1 (equivalent to 540 year-1), with fruit and vegetable expenditure being the main items making a healthy diet more expensive. Forty-nine per cent of the food budget was spent on fruit and vegetables in hdi group 8 compared to 29% in hdi group 0. Interestingly, 52% of those questioned in both extreme hdi groups did not think that it was difficult to eat healthily. To achieve a particularly healthy diet independent predictive factors were spending more money, being a vegetarian, having a higher energy intake, having a lower body mass index (BMI) and being older.

  19. Laparoscopic versus open incisional hernia repair: a retrospective cohort study with costs analysis on 269 patients.

    Science.gov (United States)

    Soliani, G; De Troia, A; Portinari, M; Targa, S; Carcoforo, P; Vasquez, G; Fisichella, P M; Feo, C V

    2017-08-01

    To compare clinical outcomes and institutional costs of elective laparoscopic and open incisional hernia mesh repairs and to identify independent predictors of prolonged operative time and hospital length of stay (LOS). Retrospective observational cohort study on 269 consecutive patients who underwent elective incisional hernia mesh repair, laparoscopic group (N = 94) and open group (N = 175), between May 2004 and July 2014. Operative time was shorter in the laparoscopic versus open group (p costs were lower (p = 0.02). At Cox regression analysis adjusted for potential confounders, large wall defect (W3) and higher operative risk (ASA score 3-4) were associated with prolonged operative time, while midline hernia site was associated with increased hospital LOS. Open surgical approach was associated with prolongation of both operative time and LOS. Laparoscopic approach may be considered safely to all patients for incisional hernia repair, regardless of patients' characteristics (age, gender, BMI, ASA score, comorbidities) and size of the wall defect (W2-3), with the advantage of shorter operating time and hospital LOS that yields reduced total institutional costs. Patients with higher ASA score and large hernia defects are at risk of prolonged operative time, while an open approach is associated with longer duration of surgical operation and hospital LOS.

  20. Job strain and risk of obesity: systematic review and meta-analysis of cohort studies.

    Science.gov (United States)

    Kivimäki, M; Singh-Manoux, A; Nyberg, S; Jokela, M; Virtanen, M

    2015-11-01

    Job strain, the most widely used indicator of work stress, is a risk factor for obesity-related disorders such as cardiovascular disease and type 2 diabetes. However, the extent to which job strain is related to the development of obesity itself has not been systematically evaluated. We carried out a systematic review (PubMed and Embase until May 2014) and meta-analysis of cohort studies to address this issue. Eight studies that fulfilled inclusion criteria showed no overall association between job strain and the risk of weight gain (pooled odds ratio for job strain compared with no job strain 1.04, 95% confidence interval (CI) 0.99-1.09, NTotal=18 240) or becoming obese (1.00, 95% CI 0.89-1.13, NTotal=42 222). In addition, a reduction in job strain over time was not associated with lower obesity risk (1.13, 95% CI 0.90-1.41, NTotal=6507). These longitudinal findings do not support the hypothesis that job strain is an important risk factor for obesity or a promising target for obesity prevention.

  1. Causal mediation analysis with multiple causally non-ordered mediators.

    Science.gov (United States)

    Taguri, Masataka; Featherstone, John; Cheng, Jing

    2018-01-01

    In many health studies, researchers are interested in estimating the treatment effects on the outcome around and through an intermediate variable. Such causal mediation analyses aim to understand the mechanisms that explain the treatment effect. Although multiple mediators are often involved in real studies, most of the literature considered mediation analyses with one mediator at a time. In this article, we consider mediation analyses when there are causally non-ordered multiple mediators. Even if the mediators do not affect each other, the sum of two indirect effects through the two mediators considered separately may diverge from the joint natural indirect effect when there are additive interactions between the effects of the two mediators on the outcome. Therefore, we derive an equation for the joint natural indirect effect based on the individual mediation effects and their interactive effect, which helps us understand how the mediation effect works through the two mediators and relative contributions of the mediators and their interaction. We also discuss an extension for three mediators. The proposed method is illustrated using data from a randomized trial on the prevention of dental caries.

  2. Causal Mediation Analysis of Survival Outcome with Multiple Mediators.

    Science.gov (United States)

    Huang, Yen-Tsung; Yang, Hwai-I

    2017-05-01

    Mediation analyses have been a popular approach to investigate the effect of an exposure on an outcome through a mediator. Mediation models with multiple mediators have been proposed for continuous and dichotomous outcomes. However, development of multimediator models for survival outcomes is still limited. We present methods for multimediator analyses using three survival models: Aalen additive hazard models, Cox proportional hazard models, and semiparametric probit models. Effects through mediators can be characterized by path-specific effects, for which definitions and identifiability assumptions are provided. We derive closed-form expressions for path-specific effects for the three models, which are intuitively interpreted using a causal diagram. Mediation analyses using Cox models under the rare-outcome assumption and Aalen additive hazard models consider effects on log hazard ratio and hazard difference, respectively; analyses using semiparametric probit models consider effects on difference in transformed survival time and survival probability. The three models were applied to a hepatitis study where we investigated effects of hepatitis C on liver cancer incidence mediated through baseline and/or follow-up hepatitis B viral load. The three methods show consistent results on respective effect scales, which suggest an adverse estimated effect of hepatitis C on liver cancer not mediated through hepatitis B, and a protective estimated effect mediated through the baseline (and possibly follow-up) of hepatitis B viral load. Causal mediation analyses of survival outcome with multiple mediators are developed for additive hazard and proportional hazard and probit models with utility demonstrated in a hepatitis study.

  3. Performance curves of medical researchers during their career: analysis of scientific production from a retrospective cohort.

    Science.gov (United States)

    Duclos, Antoine; Herquelot, Eléonore; Polazzi, Stéphanie; Malbezin, Muriel; Claris, Olivier

    2017-02-24

    To establish the pattern of change in individual scientific production over the career of medical researchers. Retrospective cohort based on prospectively collected data in a hospital information system. Multicentre university hospital in France. Two distinct populations of 1835 researchers (full professors vs non-academic physicians) having produced 44 723 publications between 1995 and 2014. Annual number of publications referenced in Medline/PubMed with a sensitivity analysis based on publications as first/last author and in high impact journals. The individual volume of publications was modelled by age using generalised estimating equations adjusted for birth cohort, biomedical discipline and academic position of researchers. Averaged over the whole career, the annual number of publications was 5.28 (95% CI 4.90 to 5.69) among professors compared to 0.82 (95% CI 0.76 to 0.89) among non-academic physicians (pscientific production between 25 and 35 years (adjusted incidence rate ratio 102.20, 95% CI 60.99 to 171.30), a maturation phase with a slower increase from 35 to 50 years (2.10, 95% CI 1.75 to 2.51) until a stabilisation phase with constant production followed by a potential decline at the end of career (0.90, 95% CI 0.77 to 1.06). The non-academic physicians experienced a slower pace of learning curve at the beginning of their careers (42.38, 95% CI 25.37 to 70.81) followed by a smaller increase in the annual number of publications (1.29, 95% CI 1.11 to 1.51). Compared to full professors, non-academic physicians had a poor capacity to publish, indicating a low productivity when medical doctors have limited time or little interest in undertaking research. This finding highlights the potential for rethinking the missions of medical doctors towards an enlargement of scientific prerogatives in favour of progress in global knowledge. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go

  4. Thyroid Function Tests in the Reference Range and Fracture: Individual Participant Analysis of Prospective Cohorts.

    Science.gov (United States)

    Aubert, Carole E; Floriani, Carmen; Bauer, Douglas C; da Costa, Bruno R; Segna, Daniel; Blum, Manuel R; Collet, Tinh-Hai; Fink, Howard A; Cappola, Anne R; Syrogiannouli, Lamprini; Peeters, Robin P; Åsvold, Bjørn O; den Elzen, Wendy P J; Luben, Robert N; Bremner, Alexandra P; Gogakos, Apostolos; Eastell, Richard; Kearney, Patricia M; Hoff, Mari; Le Blanc, Erin; Ceresini, Graziano; Rivadeneira, Fernando; Uitterlinden, André G; Khaw, Kay-Tee; Langhammer, Arnulf; Stott, David J; Westendorp, Rudi G J; Ferrucci, Luigi; Williams, Graham R; Gussekloo, Jacobijn; Walsh, John P; Aujesky, Drahomir; Rodondi, Nicolas

    2017-08-01

    Hyperthyroidism is associated with increased fracture risk, but it is not clear if lower thyroid-stimulating hormone (TSH) and higher free thyroxine (FT4) in euthyroid individuals are associated with fracture risk. To evaluate the association of TSH and FT4 with incident fractures in euthyroid individuals. Individual participant data analysis. Thirteen prospective cohort studies with baseline examinations between 1981 and 2002. Adults with baseline TSH 0.45 to 4.49 mIU/L. Primary outcome was incident hip fracture. Secondary outcomes were any, nonvertebral, and vertebral fractures. Results were presented as hazard ratios (HRs) with 95% confidence interval (CI) adjusted for age and sex. For clinical relevance, we studied TSH according to five categories: 0.45 to 0.99 mIU/L; 1.00 to 1.49 mIU/L; 1.50 to 2.49 mIU/L; 2.50 to 3.49 mIU/L; and 3.50 to 4.49 mIU/L (reference). FT4 was assessed as study-specific standard deviation increase, because assays varied between cohorts. During 659,059 person-years, 2,565 out of 56,835 participants had hip fracture (4.5%; 12 studies with data on hip fracture). The pooled adjusted HR (95% CI) for hip fracture was 1.25 (1.05 to 1.49) for TSH 0.45 to 0.99 mIU/L, 1.19 (1.01 to 1.41) for TSH 1.00 to 1.49 mIU/L, 1.09 (0.93 to 1.28) for TSH 1.50 to 2.49 mIU/L, and 1.12 (0.94 to 1.33) for TSH 2.50 to 3.49 mIU/L (P for trend = 0.004). Hip fracture was also associated with FT4 [HR (95% CI) 1.22 (1.11 to 1.35) per one standard deviation increase in FT4]. FT4 only was associated with any and nonvertebral fractures. Results remained similar in sensitivity analyses. Among euthyroid adults, lower TSH and higher FT4 are associated with an increased risk of hip fracture. These findings may help refine the definition of optimal ranges of thyroid function tests. Copyright © 2017 Endocrine Society

  5. Differences in mechanisms of failure, intraoperative findings, and surgical characteristics between single- and multiple-revision ACL reconstructions: a MARS cohort study.

    Science.gov (United States)

    Chen, James L; Allen, Christina R; Stephens, Thomas E; Haas, Amanda K; Huston, Laura J; Wright, Rick W; Feeley, Brian T

    2013-07-01

    The factors that lead to patients failing multiple anterior cruciate ligament (ACL) reconstructions are not well understood. Multiple-revision ACL reconstruction will have different characteristics than first-time revision in terms of previous and current graft selection, mode of failure, chondral/meniscal injuries, and surgical charactieristics. Case-control study; Level of evidence, 3. A prospective multicenter ACL revision database was utilized for the time period from March 2006 to June 2011. Patients were divided into those who underwent a single-revision ACL reconstruction and those who underwent multiple-revision ACL reconstructions. The primary outcome variable was Marx activity level. Primary data analyses between the groups included a comparison of graft type, perceived mechanism of failure, associated injury (meniscus, ligament, and cartilage), reconstruction type, and tunnel position. Data were compared by analysis of variance with a post hoc Tukey test. A total of 1200 patients (58% men; median age, 26 years) were enrolled, with 1049 (87%) patients having a primary revision and 151 (13%) patients having a second or subsequent revision. Marx activity levels were significantly higher (9.77) in the primary-revision group than in those patients with multiple revisions (6.74). The most common cause of reruptures was a traumatic, noncontact ACL graft injury in 55% of primary-revision patients; 25% of patients had a nontraumatic, gradual-onset recurrent injury, and 11% had a traumatic, contact injury. In the multiple-revision group, a nontraumatic, gradual-onset injury was the most common cause of recurrence (47%), followed by traumatic noncontact (35%) and nontraumatic sudden onset (11%) (P < .01 between groups). Chondral injuries in the medial compartment were significantly more common in the multiple-revision group than in the single-revision group, as were chondral injuries in the patellofemoral compartment. Patients with multiple-revision ACL

  6. Hesitant fuzzy methods for multiple criteria decision analysis

    CERN Document Server

    Zhang, Xiaolu

    2017-01-01

    The book offers a comprehensive introduction to methods for solving multiple criteria decision making and group decision making problems with hesitant fuzzy information. It reports on the authors’ latest research, as well as on others’ research, providing readers with a complete set of decision making tools, such as hesitant fuzzy TOPSIS, hesitant fuzzy TODIM, hesitant fuzzy LINMAP, hesitant fuzzy QUALIFEX, and the deviation modeling approach with heterogeneous fuzzy information. The main focus is on decision making problems in which the criteria values and/or the weights of criteria are not expressed in crisp numbers but are more suitable to be denoted as hesitant fuzzy elements. The largest part of the book is devoted to new methods recently developed by the authors to solve decision making problems in situations where the available information is vague or hesitant. These methods are presented in detail, together with their application to different type of decision-making problems. All in all, the book ...

  7. Parent involvement and student academic performance: a multiple mediational analysis.

    Science.gov (United States)

    Topor, David R; Keane, Susan P; Shelton, Terri L; Calkins, Susan D

    2010-01-01

    Parent involvement in a child's education is consistently found to be positively associated with a child's academic performance. However, there has been little investigation of the mechanisms that explain this association. The present study examines two potential mechanisms of this association: the child's perception of cognitive competence and the quality of the student-teacher relationship. This study used a sample of 158 seven-year-old participants, their mothers, and their teachers. Results indicated a statistically significant association between parent involvement and a child's academic performance, over and above the impact of the child's intelligence. A multiple mediation model indicated that the child's perception of cognitive competence fully mediated the relation between parent involvement and the child's performance on a standardized achievement test. The quality of the student-teacher relationship fully mediated the relation between parent involvement and teacher ratings of the child's classroom academic performance. Limitations, future research directions, and implications for public policy initiatives are discussed.

  8. Mission control of multiple unmanned aerial vehicles: a workload analysis.

    Science.gov (United States)

    Dixon, Stephen R; Wickens, Christopher D; Chang, Dervon

    2005-01-01

    With unmanned aerial vehicles (UAVs), 36 licensed pilots flew both single-UAV and dual-UAV simulated military missions. Pilots were required to navigate each UAV through a series of mission legs in one of the following three conditions: a baseline condition, an auditory autoalert condition, and an autopilot condition. Pilots were responsible for (a) mission completion, (b) target search, and (c) systems monitoring. Results revealed that both the autoalert and the autopilot automation improved overall performance by reducing task interference and alleviating workload. The autoalert system benefited performance both in the automated task and mission completion task, whereas the autopilot system benefited performance in the automated task, the mission completion task, and the target search task. Practical implications for the study include the suggestion that reliable automation can help alleviate task interference and reduce workload, thereby allowing pilots to better handle concurrent tasks during single- and multiple-UAV flight control.

  9. Meat intake and cause-specific mortality: a pooled analysis of Asian prospective cohort studies.

    Science.gov (United States)

    Lee, Jung Eun; McLerran, Dale F; Rolland, Betsy; Chen, Yu; Grant, Eric J; Vedanthan, Rajesh; Inoue, Manami; Tsugane, Shoichiro; Gao, Yu-Tang; Tsuji, Ichiro; Kakizaki, Masako; Ahsan, Habibul; Ahn, Yoon-Ok; Pan, Wen-Harn; Ozasa, Kotaro; Yoo, Keun-Young; Sasazuki, Shizuka; Yang, Gong; Watanabe, Takashi; Sugawara, Yumi; Parvez, Faruque; Kim, Dong-Hyun; Chuang, Shao-Yuan; Ohishi, Waka; Park, Sue K; Feng, Ziding; Thornquist, Mark; Boffetta, Paolo; Zheng, Wei; Kang, Daehee; Potter, John; Sinha, Rashmi

    2013-10-01

    Total or red meat intake has been shown to be associated with a higher risk of mortality in Western populations, but little is known of the risks in Asian populations. We examined temporal trends in meat consumption and associations between meat intake and all-cause and cause-specific mortality in Asia. We used ecological data from the United Nations to compare country-specific meat consumption. Separately, 8 Asian prospective cohort studies in Bangladesh, China, Japan, Korea, and Taiwan consisting of 112,310 men and 184,411 women were followed for 6.6 to 15.6 y with 24,283 all-cause, 9558 cancer, and 6373 cardiovascular disease (CVD) deaths. We estimated the study-specific HRs and 95% CIs by using a Cox regression model and pooled them by using a random-effects model. Red meat consumption was substantially lower in the Asian countries than in the United States. Fish and seafood consumption was higher in Japan and Korea than in the United States. Our pooled analysis found no association between intake of total meat (red meat, poultry, and fish/seafood) and risks of all-cause, CVD, or cancer mortality among men and women; HRs (95% CIs) for all-cause mortality from a comparison of the highest with the lowest quartile were 1.02 (0.91, 1.15) in men and 0.93 (0.86, 1.01) in women. Ecological data indicate an increase in meat intake in Asian countries; however, our pooled analysis did not provide evidence of a higher risk of mortality for total meat intake and provided evidence of an inverse association with red meat, poultry, and fish/seafood. Red meat intake was inversely associated with CVD mortality in men and with cancer mortality in women in Asian countries.

  10. Meat intake and cause-specific mortality: a pooled analysis of Asian prospective cohort studies123

    Science.gov (United States)

    Lee, Jung Eun; McLerran, Dale F; Rolland, Betsy; Chen, Yu; Grant, Eric J; Vedanthan, Rajesh; Inoue, Manami; Tsugane, Shoichiro; Gao, Yu-Tang; Tsuji, Ichiro; Kakizaki, Masako; Ahsan, Habibul; Ahn, Yoon-Ok; Pan, Wen-Harn; Ozasa, Kotaro; Yoo, Keun-Young; Sasazuki, Shizuka; Yang, Gong; Watanabe, Takashi; Sugawara, Yumi; Parvez, Faruque; Kim, Dong-Hyun; Chuang, Shao-Yuan; Ohishi, Waka; Park, Sue K; Feng, Ziding; Thornquist, Mark; Boffetta, Paolo; Zheng, Wei; Kang, Daehee; Potter, John; Sinha, Rashmi

    2013-01-01

    Background: Total or red meat intake has been shown to be associated with a higher risk of mortality in Western populations, but little is known of the risks in Asian populations. Objective: We examined temporal trends in meat consumption and associations between meat intake and all-cause and cause-specific mortality in Asia. Design: We used ecological data from the United Nations to compare country-specific meat consumption. Separately, 8 Asian prospective cohort studies in Bangladesh, China, Japan, Korea, and Taiwan consisting of 112,310 men and 184,411 women were followed for 6.6 to 15.6 y with 24,283 all-cause, 9558 cancer, and 6373 cardiovascular disease (CVD) deaths. We estimated the study-specific HRs and 95% CIs by using a Cox regression model and pooled them by using a random-effects model. Results: Red meat consumption was substantially lower in the Asian countries than in the United States. Fish and seafood consumption was higher in Japan and Korea than in the United States. Our pooled analysis found no association between intake of total meat (red meat, poultry, and fish/seafood) and risks of all-cause, CVD, or cancer mortality among men and women; HRs (95% CIs) for all-cause mortality from a comparison of the highest with the lowest quartile were 1.02 (0.91, 1.15) in men and 0.93 (0.86, 1.01) in women. Conclusions: Ecological data indicate an increase in meat intake in Asian countries; however, our pooled analysis did not provide evidence of a higher risk of mortality for total meat intake and provided evidence of an inverse association with red meat, poultry, and fish/seafood. Red meat intake was inversely associated with CVD mortality in men and with cancer mortality in women in Asian countries. PMID:23902788

  11. Prenatal chromosomal microarray analysis in fetuses with congenital heart disease: a prospective cohort study.

    Science.gov (United States)

    Wang, Yan; Cao, Li; Liang, Dong; Meng, Lulu; Wu, Yun; Qiao, Fengchang; Ji, Xiuqing; Luo, Chunyu; Zhang, Jingjing; Xu, Tianhui; Yu, Bin; Wang, Leilei; Wang, Ting; Pan, Qiong; Ma, Dingyuan; Hu, Ping; Xu, Zhengfeng

    2018-02-01

    Currently, chromosomal microarray analysis is considered the first-tier test in pediatric care and prenatal diagnosis. However, the diagnostic yield of chromosomal microarray analysis for prenatal diagnosis of congenital heart disease has not been evaluated based on a large cohort. Our aim was to evaluate the clinical utility of chromosomal microarray as the first-tier test for chromosomal abnormalities in fetuses with congenital heart disease. In this prospective study, 602 prenatal cases of congenital heart disease were investigated using single nucleotide polymorphism array over a 5-year period. Overall, pathogenic chromosomal abnormalities were identified in 125 (20.8%) of 602 prenatal cases of congenital heart disease, with 52.0% of them being numerical chromosomal abnormalities. The detection rates of likely pathogenic copy number variations and variants of uncertain significance were 1.3% and 6.0%, respectively. The detection rate of pathogenic chromosomal abnormalities in congenital heart disease plus additional structural anomalies (48.9% vs 14.3%, P congenital heart disease group. Additionally, the detection rate in congenital heart disease with additional structural anomalies group was significantly higher than that in congenital heart disease with soft markers group (48.9% vs 19.8%, P congenital heart disease with additional structural anomalies and congenital heart disease with intrauterine growth retardation groups (48.9% vs 50.0%), congenital heart disease with soft markers and congenital heart disease with intrauterine growth retardation groups (19.8% vs 50.0%), or congenital heart disease with soft markers and isolated congenital heart disease groups (19.8% vs 14.3%). The detection rate in fetuses with congenital heart disease plus mild ventriculomegaly was significantly higher than in those with other types of soft markers (50.0% vs 15.6%, P congenital heart disease in clinical practice. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Multiple-user data acquisition and analysis system

    International Nuclear Information System (INIS)

    Manzella, V.; Chrien, R.E.; Gill, R.L.; Liou, H.I.; Stelts, M.L.

    1981-01-01

    The nuclear physics program at the Brookhaven National Laboratory High Flux Beam Reactor (HFBR) employs a pair of PDP-11 computers for the dual functions of data acquisition and analysis. The data acquisition is accomplished through CAMAC and features a microprogrammed branch driver to accommodate various experimental inputs. The acquisition computer performs the functions of multi-channel analyzers, multiscaling and time-sequenced multichannel analyzers and gamma-ray coincidence analyzers. The data analysis computer is available for rapid processing of data tapes written by the acquisition computer. The ability to accommodate many users is facilitated by separating the data acquisition and analysis functions, and allowing each user to tailor the analysis to the specific requirements of his own experiment. The system is to be upgraded soon by the introduction of a dual port disk to allow a data base to be available to each computer

  13. A comparative study of multiple regression analysis and back ...

    Indian Academy of Sciences (India)

    Abhijit Sarkar

    artificial neural network (ANN) models to predict weld bead geometry and HAZ width in submerged arc welding ... Keywords. Submerged arc welding (SAW); multi-regression analysis (MRA); artificial neural network ..... Degree of freedom.

  14. Multiple Beta Spectrum Analysis Method Based on Spectrum Fitting

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Uk Jae; Jung, Yun Song; Kim, Hee Reyoung [UNIST, Ulsan (Korea, Republic of)

    2016-05-15

    When the sample of several mixed radioactive nuclides is measured, it is difficult to divide each nuclide due to the overlapping of spectrums. For this reason, simple mathematical analysis method for spectrum analysis of the mixed beta ray source has been studied. However, existing research was in need of more accurate spectral analysis method as it has a problem of accuracy. The study will describe the contents of the separation methods of the mixed beta ray source through the analysis of the beta spectrum slope based on the curve fitting to resolve the existing problem. The fitting methods including It was understood that sum of sine fitting method was the best one of such proposed methods as Fourier, polynomial, Gaussian and sum of sine to obtain equation for distribution of mixed beta spectrum. It was shown to be the most appropriate for the analysis of the spectrum with various ratios of mixed nuclides. It was thought that this method could be applied to rapid spectrum analysis of the mixed beta ray source.

  15. Multiple Mild Traumatic Brain Injuries Are Associated with Increased Rates of Health Symptoms and Gulf War Illness in a Cohort of 1990–1991 Gulf War Veterans

    Directory of Open Access Journals (Sweden)

    Megan K. Yee

    2017-07-01

    Full Text Available Recent research demonstrated a relation between traumatic brain injury (TBI, health symptoms and diagnosis of Gulf War Illness (GWI in Gulf War Veterans, but no study has examined the impact of multiple mild TBIs (mTBIs. A total of 229 male Gulf War Veterans from the Ft Devens Cohort were categorized by a number of mTBIs reported. One-way ANOVA and chi-square test of independence were used to test for differences in total reported health symptoms and diagnosis of chronic multisymptom illness (CMI or Kansas GWI criteria, two of the most common case definitions of GWI. A total of 72 veterans reported no mTBIs (31.4%, 26 reported one mTBI (11.4%, 25 reported two mTBIs (10.9%, and 106 veterans reported sustaining three or more mTBIs (46.3%. Veterans reporting two or more mTBIs (p < 0.01 or three or more mTBIs (p < 0.001 endorsed significantly higher rates of health symptoms than Veterans reporting no mTBIs. Significantly higher rates of CMI (p = 0.035 and Kansas GWI criteria (p < 0.001 were seen in the three or more mTBI group. Results suggest two mTBIs increase risk of health symptoms, but three mTBIs may be the threshold needed to sustain chronic symptom reporting needed for a formal diagnosis. These findings highlight the importance of implementing policies and procedures monitoring head injuries in military personnel.

  16. Multiple mini-interview as a predictor of performance in the objective structured clinical examination among Physician Associates in the United Kingdom: a cohort study

    Science.gov (United States)

    Kumar, Narendra; Bhardwaj, Shailaja; Rahman, Eqram

    2018-01-01

    Introduction Patient satisfaction and health care outcomes are directly linked to useful communication skills. Therefore, excellent interpersonal skills are imperative for health care professionals. Multiple mini-interview (MMI) is designed as a selection tool to assess the communication skills of applicants in medical schools during the admission process. However, objective structured clinical examination (OSCE) assesses students’ communication and clinical skills at the end of their academic terms. Recently, Anglia Ruskin University, Chelmsford, UK, adopted MMI in the selection process for the first cohort of MSc Physician Associate trainees for the academic year 2015–2016. This study aimed to determine the likelihood of MMI as a predictor of future performance of communication skills in the OSCE. Materials and methods The anonymous data of the average scores of communication skills attained in MMI and OSCE at the end of year 1 were collected for 30 students from the Physician Associate program team. Subsequently, Pearson’s correlation was computed to determine the relationship between the average scores of communication skills attained in MMI, and OSCE during trimester 2 and trimester 3 by the Physician Associate trainees. Results The study showed positive correlation between the scores of communication skills attained in MMI and OSCE during trimester 2 (r=0.956, n=30, p<0.001) and trimester 3 (r=0.966, n=30, p<0.001). Conclusion The study provides empirical evidence for the validity of MMI as a predictor of future performance of Physician Associate trainees’ communication skills during subsequent OSCEs. PMID:29695944

  17. Multiple pregnancies with complete mole and coexisting normal fetus in North and South America: A retrospective multicenter cohort and literature review.

    Science.gov (United States)

    Lin, Lawrence H; Maestá, Izildinha; Braga, Antonio; Sun, Sue Y; Fushida, Koji; Francisco, Rossana P V; Elias, Kevin M; Horowitz, Neil; Goldstein, Donald P; Berkowitz, Ross S

    2017-04-01

    To determine the clinical characteristics of multiple gestation with complete mole and coexisting fetus (CHMCF) in North and South America. Retrospective non-concurrent cohorts compromised of CHMCF from New England Trophoblastic Disease Center (NETDC) (1966-2015) and four Brazilian Trophoblastic Disease Centers (BTDC) (1990-2015). From a total of 12,455 cases of gestational trophoblastic disease seen, 72 CHMCF were identified. Clinical characteristics were similar between BTDC (n=46) and NETDC (n=13) from 1990 to 2015, apart from a much higher frequency of potentially life-threatening conditions in Brazil (p=0.046). There were no significant changes in the clinical presentation or outcomes over the past 5 decades in NETDC (13 cases in 1966-1989 vs 13 cases in 1990-2015). Ten pregnancies were electively terminated and 35 cases resulted in viable live births (60% of 60 continued pregnancies). The overall rate of gestational trophoblastic neoplasia (GTN) was 46%; the cases which progressed to GTN presented with higher chorionic gonadotropin levels (p=0.026) and higher frequency of termination of pregnancy due to medical complications (p=0.006) when compared to those with spontaneous remission. The main regional difference in CHMCF presentation is related to a higher rate of potentially life-threatening conditions in South America. Sixty percent of the expectantly managed CHMCF delivered a viable infant, and the overall rate of GTN in this study was 46%. Elective termination of pregnancy did not influence the risk for GTN; however the need for termination due to complications and higher hCG levels were associated with development of GTN in CHMCF. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Association of the interferon signature metric with serological disease manifestations but not global activity scores in multiple cohorts of patients with SLE

    Science.gov (United States)

    Kennedy, William P; Maciuca, Romeo; Wolslegel, Kristen; Tew, Wei; Abbas, Alexander R; Chaivorapol, Christina; Morimoto, Alyssa; McBride, Jacqueline M; Brunetta, Paul; Richardson, Bruce C; Davis, John C; Behrens, Timothy W; Townsend, Michael J

    2015-01-01

    Objectives The interferon (IFN) signature (IS) in patients with systemic lupus erythematosus (SLE) includes over 100 genes induced by type I IFN pathway activation. We developed a method to quantify the IS using three genes—the IS metric (ISM)—and characterised the clinical characteristics of patients with SLE with different ISM status from multiple clinical trials. Methods Blood microarray expression data from a training cohort of patients with SLE confirmed the presence of the IS and identified surrogate genes. We assayed these genes in a quantitative PCR (qPCR) assay, yielding an ISM from the IS. The association of ISM status with clinical disease characteristics was assessed in patients with extrarenal lupus and lupus nephritis from four clinical trials. Results Three genes, HERC5, EPSTI and CMPK2, correlated well with the IS (p>0.96), and composed the ISM qPCR assay. Using the 95th centile for healthy control data, patients with SLE from different studies were classified into two ISM subsets—ISM-Low and ISM-High—that are longitudinally stable over 36 weeks. Significant associations were identified between ISM-High status and higher titres of anti-dsDNA antibodies, presence of anti extractable nuclear antigen autoantibodies, elevated serum B cell activating factor of the tumour necrosis factor family (BAFF) levels, and hypocomplementaemia. However, measures of overall clinical disease activity were similar for ISM-High and ISM-Low groups. Conclusions The ISM is an IS biomarker that divides patients with SLE into two subpopulations—ISM-High and ISM-Low—with differing serological manifestations. The ISM does not distinguish between high and low disease activity, but may have utility in identifying patients more likely to respond to treatment(s) targeting IFN-α. Clinicaltrials.gov registration number NCT00962832. PMID:25861459

  19. Proceedings of the workshop on multiple prompt gamma-ray analysis

    International Nuclear Information System (INIS)

    Ebihara, Mitsuru; Hatsukawa, Yuichi; Oshima, Masumi

    2006-10-01

    The workshop on 'Multiple Prompt Gamma-ray Analysis' was held on March 8, 2006 at Tokai. It is based on a project, 'Developments of real time, non-destructive ultra sensitive elemental analysis using multiple gamma-ray detections and prompt gamma ray analysis and its application to real samples', one of the High priority Cooperative Research Programs performed by Japan Atomic Energy Agency and the University of Tokyo. In this workshop, the latest results of the Multiple Prompt Gamma ray Analysis (MPGA) study were presented, together with those of Neutron Activation Analysis with Multiple Gamma-ray Detection (NAAMG). The 9 of the presented papers are indexed individually. (J.P.N.)

  20. Image analysis of multiple moving wood pieces in real time

    Science.gov (United States)

    Wang, Weixing

    2006-02-01

    This paper presents algorithms for image processing and image analysis of wood piece materials. The algorithms were designed for auto-detection of wood piece materials on a moving conveyor belt or a truck. When wood objects on moving, the hard task is to trace the contours of the objects in n optimal way. To make the algorithms work efficiently in the plant, a flexible online system was designed and developed, which mainly consists of image acquisition, image processing, object delineation and analysis. A number of newly-developed algorithms can delineate wood objects with high accuracy and high speed, and in the wood piece analysis part, each wood piece can be characterized by a number of visual parameters which can also be used for constructing experimental models directly in the system.

  1. Stability analysis of multiple-robot control systems

    Science.gov (United States)

    Wen, John T.; Kreutz, Kenneth

    1989-01-01

    In a space telerobotic service scenario, cooperative motion and force control of multiple robot arms are of fundamental importance. Three paradigms to study this problem are proposed. They are distinguished by the set of variables used for control design. They are joint torques, arm tip force vectors, and an accelerated generalized coordinate set. Control issues related to each case are discussed. The latter two choices require complete model information, which presents practical modeling, computational, and robustness problems. Therefore, focus is on the joint torque control case to develop relatively model independent motion and internal force control laws. The rigid body assumption allows the motion and force control problems to be independently addressed. By using an energy motivated Lyapunov function, a simple proportional derivative plus gravity compensation type of motion control law is always shown to be stabilizing. The asymptotic convergence of the tracing error to zero requires the use of a generalized coordinate with the contact constraints taken into account. If a non-generalized coordinate is used, only convergence to a steady state manifold can be concluded. For the force control, both feedforward and feedback schemes are analyzed. The feedback control, if proper care has been taken, exhibits better robustness and transient performance.

  2. Phylogenetic analysis reveals multiple introductions of Cynodon species in Australia.

    Science.gov (United States)

    Jewell, M; Frère, C H; Harris-Shultz, K; Anderson, W F; Godwin, I D; Lambrides, C J

    2012-11-01

    The distinction between native and introduced flora within isolated land masses presents unique challenges. The geological and colonisation history of Australia, the world's largest island, makes it a valuable system for studying species endemism, introduction, and phylogeny. Using this strategy we investigated Australian cosmopolitan grasses belonging to the genus Cynodon. While it is believed that seven species of Cynodon are present in Australia, no genetic analyses have investigated the origin, diversity and phylogenetic history of Cynodon within Australia. To address this gap, 147 samples (92 from across Australia and 55 representing global distribution) were sequenced for a total of 3336bp of chloroplast DNA spanning six genes. Data showed the presence of at least six putatively introduced Cynodon species (C. transvaalensis, C. incompletus, C. hirsutus, C. radiatus, C. plectostachyus and C. dactylon) in Australia and suggested multiple recent introductions. C. plectostachyus, a species often confused with C. nlemfuensis, was not previously considered to be present in Australia. Most significantly, we identified two common haplotypes that formed a monophyletic clade diverging from previously identified Cynodon species. We hypothesise that these two haplotypes may represent a previously undescribed species of Cynodon. We provide further evidence that two Australian native species, Brachyachne tenella and B. convergens belong in the genus Cynodon and, therefore, argue for the taxonomic revision of the genus Cynodon. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Assembly, Annotation, and Analysis of Multiple Mycorrhizal Fungal Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Initiative Consortium, Mycorrhizal Genomics; Kuo, Alan; Grigoriev, Igor; Kohler, Annegret; Martin, Francis

    2013-03-08

    Mycorrhizal fungi play critical roles in host plant health, soil community structure and chemistry, and carbon and nutrient cycling, all areas of intense interest to the US Dept. of Energy (DOE) Joint Genome Institute (JGI). To this end we are building on our earlier sequencing of the Laccaria bicolor genome by partnering with INRA-Nancy and the mycorrhizal research community in the MGI to sequence and analyze dozens of mycorrhizal genomes of all Basidiomycota and Ascomycota orders and multiple ecological types (ericoid, orchid, and ectomycorrhizal). JGI has developed and deployed high-throughput sequencing techniques, and Assembly, RNASeq, and Annotation Pipelines. In 2012 alone we sequenced, assembled, and annotated 12 draft or improved genomes of mycorrhizae, and predicted ~;;232831 genes and ~;;15011 multigene families, All of this data is publicly available on JGI MycoCosm (http://jgi.doe.gov/fungi/), which provides access to both the genome data and tools with which to analyze the data. Preliminary comparisons of the current total of 14 public mycorrhizal genomes suggest that 1) short secreted proteins potentially involved in symbiosis are more enriched in some orders than in others amongst the mycorrhizal Agaricomycetes, 2) there are wide ranges of numbers of genes involved in certain functional categories, such as signal transduction and post-translational modification, and 3) novel gene families are specific to some ecological types.

  4. Analysis and application of opinion model with multiple topic interactions.

    Science.gov (United States)

    Xiong, Fei; Liu, Yun; Wang, Liang; Wang, Ximeng

    2017-08-01

    To reveal heterogeneous behaviors of opinion evolution in different scenarios, we propose an opinion model with topic interactions. Individual opinions and topic features are represented by a multidimensional vector. We measure an agent's action towards a specific topic by the product of opinion and topic feature. When pairs of agents interact for a topic, their actions are introduced to opinion updates with bounded confidence. Simulation results show that a transition from a disordered state to a consensus state occurs at a critical point of the tolerance threshold, which depends on the opinion dimension. The critical point increases as the dimension of opinions increases. Multiple topics promote opinion interactions and lead to the formation of macroscopic opinion clusters. In addition, more topics accelerate the evolutionary process and weaken the effect of network topology. We use two sets of large-scale real data to evaluate the model, and the results prove its effectiveness in characterizing a real evolutionary process. Our model achieves high performance in individual action prediction and even outperforms state-of-the-art methods. Meanwhile, our model has much smaller computational complexity. This paper provides a demonstration for possible practical applications of theoretical opinion dynamics.

  5. Retinal ganglion cell analysis in multiple sclerosis and optic neuritis

    DEFF Research Database (Denmark)

    Britze, Josefine; Pihl-Jensen, Gorm; Frederiksen, Jette Lautrup

    2017-01-01

    of Science and Scopus. Studies were included if they measured GCL thickness using OCT in patients with either ON, MS or clinically isolated syndrome. For the meta-analysis, we compared GCL thickness in MS patients with and without prior ON, to healthy controls. 42/252 studies were reviewed. In acute ON...

  6. Quantitative electron microscope autoradiography: application of multiple linear regression analysis

    International Nuclear Information System (INIS)

    Markov, D.V.

    1986-01-01

    A new method for the analysis of high resolution EM autoradiographs is described. It identifies labelled cell organelle profiles in sections on a strictly statistical basis and provides accurate estimates for their radioactivity without the need to make any assumptions about their size, shape and spatial arrangement. (author)

  7. Multiple analysis of an unknown optical multilayer coating

    International Nuclear Information System (INIS)

    Dobrowolski, J.A.; Ho, F.C.; Waldorf, A.

    1985-01-01

    Results are given of the analysis at five different laboratories of an unknown optical multilayer coating. In all, eleven different analytical and laboratory techniques were applied to the problem. The multilayer nominally consisted of three dielectric and two metallic layers. It was demonstrated convincingly that with present day techniques it is possible to determine the basic structure of such a coating

  8. Sloshing analysis of tanks containing multiple fluid layers

    International Nuclear Information System (INIS)

    Uras, R.A.; Tang, Yu.

    1994-01-01

    The effect of liquid density changes in high level radioactive liquid waste storage tanks is studied. The density variations with the liquid depth is modeled by layers of piece wise constant densities. A computational formulation based on the finite element method is presented. The computer code FLUSTR-ANL has been modified for the analysis of the sloshing response under seismic excitation

  9. Essays on Systemic Risk : An analysis from multiple perspectives

    NARCIS (Netherlands)

    S. Muns (Sander)

    2016-01-01

    markdownabstractThis thesis is about systemic risk in the financial sector. It considers several aspects of systemic risk. It is a building block for an analysis of the impact of systemic risk on the real economy. It appears that stocks in the financial industry show a strong interdependence

  10. [Modular risk analysis for assessing multiple waste sites]: Proceedings

    International Nuclear Information System (INIS)

    Whelan, G.

    1994-01-01

    This document contains proceedings from the Integrated Planning Workshop from Strategic Planning to Baselining and Other Objectives. Topics discussed include: stakeholder involvement; regulations; future site use planning; site integration and baseline methods; risk analysis in decision making; land uses; and economics in decision making. Individual records have been processed separately for the database

  11. Dog Ownership and Mortality in England: A Pooled Analysis of Six Population-based Cohorts.

    Science.gov (United States)

    Ding, Ding; Bauman, Adrian E; Sherrington, Cathie; McGreevy, Paul D; Edwards, Kate M; Stamatakis, Emmanuel

    2018-02-01

    Dog ownership may be associated with reduced risk for cardiovascular disease. However, data are scant on the relationship between dog ownership and all-cause and cause-specific mortality risk. Data from six separate cohorts (1995-1997, 2001-2002, 2004) of the Health Survey for England were pooled and analyzed in 2017. Participants were 59,352 adults (mean age 46.5, SD=17.9 years) who consented to be linked to the National Death Registry. Living in a household with a dog was reported at baseline. Outcomes included all-cause and cardiovascular disease mortality (determined using ICD-9 codes 390-459, ICD-10 codes I01-I99). Multilevel Weibull survival analysis was used to examine the associations between dog ownership and mortality, adjusted for various sociodemographic and lifestyle variables. Potential effect modifiers, including age, sex, education, living circumstances, longstanding illness, and prior diagnosis of cardiovascular disease, were also examined. During 679,441 person-years of follow-up (mean 11.5, SD=3.8 years), 8,169 participants died from all causes and 2,451 from cardiovascular disease. In the fully adjusted models, there was no statistically significant association between dog ownership and mortality outcomes (hazard ratio=1.03, 95% CI=0.98, 1.09, for all-cause mortality; and hazard ratio=1.07, 95% CI=0.96, 1.18, for cardiovascular disease mortality) and no significant effect modification. There is no evidence for an association between living in a household with a dog and all-cause or cardiovascular disease mortality in this large sample. These results should be interpreted in light of limitations in the measurement of dog ownership and its complexity in potential long-term health implications. Future studies should measure specific aspects of ownership, such as caring responsibilities and temporality. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  12. Early EEG for outcome prediction of postanoxic coma: prospective cohort study with cost-minimization analysis.

    Science.gov (United States)

    Sondag, Lotte; Ruijter, Barry J; Tjepkema-Cloostermans, Marleen C; Beishuizen, Albertus; Bosch, Frank H; van Til, Janine A; van Putten, Michel J A M; Hofmeijer, Jeannette

    2017-05-15

    We recently showed that electroencephalography (EEG) patterns within the first 24 hours robustly contribute to multimodal prediction of poor or good neurological outcome of comatose patients after cardiac arrest. Here, we confirm these results and present a cost-minimization analysis. Early prognosis contributes to communication between doctors and family, and may prevent inappropriate treatment. A prospective cohort study including 430 subsequent comatose patients after cardiac arrest was conducted at intensive care units of two teaching hospitals. Continuous EEG was started within 12 hours after cardiac arrest and continued up to 3 days. EEG patterns were visually classified as unfavorable (isoelectric, low-voltage, or burst suppression with identical bursts) or favorable (continuous patterns) at 12 and 24 hours after cardiac arrest. Outcome at 6 months was classified as good (cerebral performance category (CPC) 1 or 2) or poor (CPC 3, 4, or 5). Predictive values of EEG measures and cost-consequences from a hospital perspective were investigated, assuming EEG-based decision- making about withdrawal of life-sustaining treatment in the case of a poor predicted outcome. Poor outcome occurred in 197 patients (51% of those included in the analyses). Unfavorable EEG patterns at 24 hours predicted a poor outcome with specificity of 100% (95% CI 98-100%) and sensitivity of 29% (95% CI 22-36%). Favorable patterns at 12 hours predicted good outcome with specificity of 88% (95% CI 81-93%) and sensitivity of 51% (95% CI 42-60%). Treatment withdrawal based on an unfavorable EEG pattern at 24 hours resulted in a reduced mean ICU length of stay without increased mortality in the long term. This gave small cost reductions, depending on the timing of withdrawal. Early EEG contributes to reliable prediction of good or poor outcome of postanoxic coma and may lead to reduced length of ICU stay. In turn, this may bring small cost reductions.

  13. Socioeconomic inequalities in resilience and vulnerability among older adults: a population-based birth cohort analysis.

    Science.gov (United States)

    Cosco, T D; Cooper, R; Kuh, D; Stafford, M

    2017-11-08

    Aging is associated with declines in physical capability; however, some individuals demonstrate high well-being despite this decline, i.e. they are "resilient." We examined socioeconomic position (SEP) and resilience and the influence of potentially modifiable behavioral resources, i.e. social support and leisure time physical activity (LTPA), on these relationships. Data came from the Medical Research Council National Survey of Health and Development, a nationally-representative birth cohort study. Resilience-vulnerability at age 60-64 years (n = 1,756) was operationalized as the difference between observed and expected levels of well-being, captured by the Warwick-Edinburgh Mental Well-being Scale (WEMWBS), given the level of performance-based physical capability. SEP was assessed by father's and own social class, parental education, and intergenerational social mobility. PA and structural/functional social support were reported at ages 53 years and 60-64 years. Path analysis was used to examine mediation of SEP and resilience-vulnerability through LTPA and social support. Participants in the highest social class had scores on the resilience to vulnerability continuum that were an average of 2.3 units (β = 0.46, 95% CI 0.17, 0.75) higher than those in the lowest social class. Greater LTPA (β = 0.58, 95% CI 0.31, 0.85) and social support (β = 3.27, 95% CI 2.90, 3.63) were associated with greater resilience; LTPA partly mediated participant social class and resilience (23.4% of variance). Adult socioeconomic advantage was associated with greater resilience. Initiatives to increase LTPA may contribute to reducing socioeconomic inequalities in this form of resilience in later life.

  14. Genetic analysis of high bone mass cases from the BARCOS cohort of Spanish postmenopausal women.

    Directory of Open Access Journals (Sweden)

    Patricia Sarrión

    Full Text Available The aims of the study were to establish the prevalence of high bone mass (HBM in a cohort of Spanish postmenopausal women (BARCOS and to assess the contribution of LRP5 and DKK1 mutations and of common bone mineral density (BMD variants to a HBM phenotype. Furthermore, we describe the expression of several osteoblast-specific and Wnt-pathway genes in primary osteoblasts from two HBM cases. A 0.6% of individuals (10/1600 displayed Z-scores in the HBM range (sum Z-score >4. While no mutation in the relevant exons of LRP5 was detected, a rare missense change in DKK1 was found (p.Y74F, which cosegregated with the phenotype in a small pedigree. Fifty-five BMD SNPs from Estrada et al. [NatGenet 44:491-501,2012] were genotyped in the HBM cases to obtain risk scores for each individual. In this small group of samples, Z-scores were found inversely related to risk scores, suggestive of a polygenic etiology. There was a single exception, which may be explained by a rare penetrant genetic variant, counterbalancing the additive effect of the risk alleles. The expression analysis in primary osteoblasts from two HBM cases and five controls suggested that IL6R, DLX3, TWIST1 and PPARG are negatively related to Z-score. One HBM case presented with high levels of RUNX2, while the other displayed very low SOX6. In conclusion, we provide evidence of lack of LRP5 mutations and of a putative HBM-causing mutation in DKK1. Additionally, we present SNP genotyping and expression results that suggest additive effects of several genes for HBM.

  15. Acute viral bronchiolitis and risk of asthma in schoolchildren: analysis of a Brazilian newborn cohort.

    Science.gov (United States)

    Brandão, Heli V; Vieira, Graciete O; Vieira, Tatiana O; Cruz, Álvaro A; Guimarães, Armênio C; Teles, Carlos; Camargos, Paulo; Cruz, Constança M S

    To verify whether the occurrence of acute viral bronchiolitis in the first year of life constitutes a risk factor for asthma at age 6 considering a parental history of asthma. Cross-sectional study in a cohort of live births. A standardized questionnaire of the International Study of Asthma and Allergies in Childhood was applied to the mothers to identify asthma in children at the age of 6 years. Acute viral bronchiolitis diagnosis was performed by maternal report of a medical diagnosis and/or presence of symptoms of coryza accompanied by cough, tachypnea, and dyspnea when participants were 3, 6, 9, and 12 months. Socioeconomic, environmental data, parental history of asthma, and data related to pregnancy were collected in the first 72h of life of the newborn and in prospective home visits by trained interviewers. The association between acute viral bronchiolitis and asthma was evaluated by logistic regression analysis and potential modifier effect of parental history was verified by introducing an interaction term into the adjusted logistic regression model. Prevalence of acute viral bronchiolitis in the first year of life was 68.6% (461). The occurrence of acute viral bronchiolitis was a risk factor for asthma at 6 years of age in children with parental history of asthma OR: 2.66, 95% CI (1.10-6.40), modifier effect p=0.002. Parental history of asthma OR: 2.07, 95% CI (1.29-3.30) and male gender OR: 1.69, 95% CI, (1.06-2.69) were other identified risk factors for asthma. Acute viral bronchiolitis in the first year of life is a risk factor for asthma in children with parental history of asthma. Copyright © 2016. Published by Elsevier Editora Ltda.

  16. Acute viral bronchiolitis and risk of asthma in schoolchildren: analysis of a Brazilian newborn cohort,

    Directory of Open Access Journals (Sweden)

    Heli V. Brandão

    Full Text Available Abstract Objective: To verify whether the occurrence of acute viral bronchiolitis in the first year of life constitutes a risk factor for asthma at age 6 considering a parental history of asthma. Methods: Cross-sectional study in a cohort of live births. A standardized questionnaire of the International Study of Asthma and Allergies in Childhood was applied to the mothers to identify asthma in children at the age of 6 years. Acute viral bronchiolitis diagnosis was performed by maternal report of a medical diagnosis and/or presence of symptoms of coryza accompanied by cough, tachypnea, and dyspnea when participants were 3, 6, 9, and 12 months. Socioeconomic, environmental data, parental history of asthma, and data related to pregnancy were collected in the first 72 h of life of the newborn and in prospective home visits by trained interviewers. The association between acute viral bronchiolitis and asthma was evaluated by logistic regression analysis and potential modifier effect of parental history was verified by introducing an interaction term into the adjusted logistic regression model. Results: Prevalence of acute viral bronchiolitis in the first year of life was 68.6% (461. The occurrence of acute viral bronchiolitis was a risk factor for asthma at 6 years of age in children with parental history of asthma OR: 2.66, 95% CI (1.10-6.40, modifier effect p = 0.002. Parental history of asthma OR: 2.07, 95% CI (1.29-3.30 and male gender OR: 1.69, 95% CI, (1.06-2.69 were other identified risk factors for asthma. Conclusion: Acute viral bronchiolitis in the first year of life is a risk factor for asthma in children with parental history of asthma.

  17. Trends in mouth cancer incidence in Mumbai, India (1995-2009): An age-period-cohort analysis.

    Science.gov (United States)

    Shridhar, Krithiga; Rajaraman, Preetha; Koyande, Shravani; Parikh, Purvish M; Chaturvedi, Pankaj; Dhillon, Preet K; Dikshit, Rajesh P

    2016-06-01

    Despite tobacco control and health promotion efforts, the incidence rates of mouth cancer are increasing across most regions in India. Analysing the influence of age, time period and birth cohort on these secular trends can point towards underlying factors and help identify high-risk populations for improved cancer control programmes. We evaluated secular changes in mouth cancer incidence among men and women aged 25-74 years in Mumbai between 1995 and 2009 by calculating age-specific and age-standardized incidence rates (ASR). We estimated the age-adjusted linear trend for annual percent change (EAPC) using the drift parameter, and conducted an age-period-cohort (APC) analysis to quantify recent time trends and to evaluate the significance of birth cohort and calendar period effects. Over the 15-year period, age-standardized incidence rates of mouth cancer in men in Mumbai increased by 2.7% annually (95% CI:1.9 to 3.4), pMumbai cancer registry indicate a significant linear increase of mouth cancer incidence from 1995 to 2009 in men, which was driven by younger men aged 25-49 years, and a non-significant upward trend in similarly aged younger women. Health promotion efforts should more effectively target younger cohorts. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Nitrosourea efficacy in high-grade glioma: a survival gain analysis summarizing 504 cohorts with 24193 patients.

    Science.gov (United States)

    Wolff, Johannes E A; Berrak, Su; Koontz Webb, Susannah E; Zhang, Ming

    2008-05-01

    Even though past studies have suggested efficacy of nitrosourea drugs in patients with high-grade glioma and temozolomide has recently been shown significantly to be beneficial, no conclusive comparisons between these agents have been published. We performed a survival gain analysis of 364 studies describing 24,193 patients with high-grade glioma treated in 504 cohorts, and compared the effects of drugs. The most frequent diagnoses were glioblastoma multiforme (GBM) (72%) and anaplastic astrocytoma (22%). The mean overall survival (mOS) was 14.1 months. The outcome was influenced by several of the known prognostic factors including the histological grade, if the tumors were newly diagnosed or recurrent, the completeness of resection, patients' age, and gender. This information allowed the calculation of a predicted mOS for each cohort based on their prognostic factors independent of treatment. Survival gain to characterize the influence of treatment was subsequently defined and validated as the difference between the observed and the predicted mOS. In 62 CCNU-treated cohorts and 15 ACNU-treated cohorts the survival gain was 5.3 months and 8.9 months (P < 0.0005), respectively. No detectable survival gain for patients treated with various BCNU-containing regimens was found. Conclusion CCNU- and ACNU-containing regimens were superior to BCNU containing regiments.

  19. Occupation and multiple myeloma: an occupation and industry analysis.

    Science.gov (United States)

    Gold, Laura S; Milliken, Kevin; Stewart, Patricia; Purdue, Mark; Severson, Richard; Seixas, Noah; Blair, Aaron; Davis, Scott; Hartge, Patricia; De Roos, Anneclaire J

    2010-08-01

    Multiple myeloma (MM) is an incurable plasma cell malignancy with a poorly understood etiology. The purpose of our research was to examine the relationships between lifetime occupations and MM in a relatively large case-control study. MM cases (n = 180) were identified through cancer registries in the Seattle-Puget Sound area and Detroit. Population-based controls (n = 481) were identified using random digit dialing and Medicare and Medicaid Services files. In-person interviews were conducted to ascertain occupational histories. Standard occupational classification (SOC) and standard industrial classification (SIC) codes were assigned to each job held by each participant. Unconditional logistic regression was used to generate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between MM and having ever worked in each occupation/industry and according to duration of employment in an occupation/industry. The risk of MM was associated with several manufacturing occupations and industries, including machine operators and tenders, not elsewhere classified (SOC 76) (OR = 1.8, CI = 1.0-3.3); textile, apparel, and furnishing machine operators and tenders (SOC 765) (OR = 6.0, CI = 1.7-21); and machinery manufacturing, except electrical (SIC 35) (OR = 3.3, CI = 1.7-6.7). Several service occupations and industries, such as food and beverage preparation (SOC 521) (OR = 2.0, CI = 1.1-3.8), were also associated with MM. One occupation that has been associated with MM in several previous studies, painters, paperhangers, and plasterers (SOC 644) was associated with a non-significantly elevated risk (OR = 3.6, CI = 0.7-19). We found associations between the risk of MM and employment in several manufacturing and service-related occupations and industries. Copyright 2010 Wiley-Liss, Inc.

  20. Robustness of Multiple Objective Decision Analysis Preference Functions

    Science.gov (United States)

    2002-06-01

    Bayesian Decision Theory and Utilitarian Ethics ,” American Economic Review Papers and Proceedings, 68: 223-228 (May 1978). Hartsough, Bruce R. “A...1983). Morrell, Darryl and Eric Driver. “ Bayesian Network Implementation of Levi’s Epistemic Utility Decision Theory ,” International Journal Of...elicitation efficiency for the decision maker. Subject Terms Decision Analysis, Utility Theory , Elicitation Error, Operations Research, Decision

  1. Interventional effects for mediation analysis with multiple mediators

    OpenAIRE

    Vansteelandt, Stijn; Daniel, Rhian M.

    2017-01-01

    The mediation formula for the identification of natural (in)direct effects has facilitated mediation analyses that better respect the nature of the data, with greater consideration of the need for confounding control. The default assumptions on which it relies are strong, however. In particular, they are known to be violated when confounders of the mediator–outcome association are affected by the exposure. This complicates extensions of counterfactual-based mediation analysis to settings that...

  2. Market segmentation for multiple option healthcare delivery systems--an application of cluster analysis.

    Science.gov (United States)

    Jarboe, G R; Gates, R H; McDaniel, C D

    1990-01-01

    Healthcare providers of multiple option plans may be confronted with special market segmentation problems. This study demonstrates how cluster analysis may be used for discovering distinct patterns of preference for multiple option plans. The availability of metric, as opposed to categorical or ordinal, data provides the ability to use sophisticated analysis techniques which may be superior to frequency distributions and cross-tabulations in revealing preference patterns.

  3. Treatment patterns and health care resource utilization associated with dalfampridine extended release in multiple sclerosis: a retrospective claims database analysis

    Directory of Open Access Journals (Sweden)

    Guo A

    2016-05-01

    Full Text Available Amy Guo,1 Michael Grabner,2 Swetha Rao Palli,2 Jessica Elder,1 Matthew Sidovar,1 Peter Aupperle,1 Stephen Krieger3 1Acorda Therapeutics Inc., Ardsley, New York, NY, USA; 2HealthCore Inc., Wilmington, DE, USA; 3Corinne Goldsmith Dickinson Center for MS, Icahn School of Medicine at Mount Sinai, New York, NY, USA Background: Although previous studies have demonstrated the clinical benefits of dalfampridine extended release (D-ER tablets in patients with multiple sclerosis (MS, there are limited real-world data on D-ER utilization and associated outcomes in patients with MS. Purpose: The objective of this study was to evaluate treatment patterns, budget impact, and health care resource utilization (HRU associated with D-ER use in a real-world setting. Methods: A retrospective claims database analysis was conducted using the HealthCore Integrated Research DatabaseSM. Adherence (measured by medication possession ratio, or [MPR] and persistence (measured by days between initial D-ER claim and discontinuation or end of follow-up were evaluated over 1-year follow-up. Budget impact was calculated as cost per member per month (PMPM over the available follow-up period. D-ER and control cohorts were propensity-score matched on baseline demographics, comorbidities, and MS-related resource utilization to compare walking-impairment-related HRU over follow-up. Results: Of the 2,138 MS patients identified, 1,200 were not treated with D-ER (control and 938 were treated with D-ER. Patients were aged 51 years on average and 74% female. Approximately 82.6% of D-ER patients were adherent (MPR >80%. The estimated budget impact range of D-ER was $0.014–$0.026 PMPM. Propensity-score-matched D-ER and controls yielded 479 patients in each cohort. Postmatching comparison showed that the D-ER cohort was associated with fewer physician (21.5% vs 62.4%, P<0.0001 and other outpatient visits (22.8% vs 51.4%, P<0.0001 over the 12-month follow-up. Changes in HRU from follow

  4. A personalized, intense physical rehabilitation program improves walking in people with multiple sclerosis presenting with different levels of disability: a retrospective cohort.

    Science.gov (United States)

    Kalron, Alon; Nitzani, Dalia; Magalashvili, David; Dolev, Mark; Menascu, Shay; Stern, Yael; Rosenblum, Uri; Pasitselsky, Diana; Frid, Lior; Zeilig, Gabi; Barmatz, Caroline; Givon, Uri; Achiron, Anat

    2015-03-04

    People with multiple sclerosis (PwMS) endure walking limitations. To address this restriction, various physical rehabilitation programs have been implemented with no consensus regarding their efficacy. Our objective was to report on the efficacy of an integrated tailored physical rehabilitation program on walking in people with multiple sclerosis categorized according to their level of neurological disability. Retrospective data were examined and analyzed. Specifically, data obtained from all patients who participated in the Multiple Sclerosis Center's 3 week rehabilitation program were extracted for in depth exploration. The personalized rehabilitation program included three major components modified according to the patient's specific impairments and functional needs: (a) goal directed physical therapy (b) moderately intense aerobic exercise training on a bicycle ergometer and (c) aquatic therapy chiefly oriented to body structures appropriate to movement. Gait outcome measurements included the 10 meter, 20 meter, Timed up and go and 2 minute walking tests measured pre and post the rehabilitation program. Three hundred and twelve people with relapsing-remitting multiple sclerosis were included in the final analysis. Patients were categorized into mild (n = 87), moderate (n = 104) and severely (n = 121) disabled groups. All clinical walking outcome measurements demonstrated statistically significant improvements, however, only an increase in the 2 minute walking test was above the minimal clinical difference value. The moderate and severe groups considerably improved compared to the mild gait disability group. Mean change scores (%) of the pre-post intervention period of the 2 minute walking test were 19.0 (S.E. = 3.4) in the moderate group, 16.2 (S.E. = 5.4) in the severe group and 10.9 (S.E. = 2.3) in the mild gait disability group. We presented comprehensive evidence verifying the effects of an intense goal-directed physical

  5. Assessment of participation bias in cohort studies: systematic review and meta-regression analysis

    Directory of Open Access Journals (Sweden)

    Sérgio Henrique Almeida da Silva Junior

    2015-11-01

    Full Text Available Abstract The proportion of non-participation in cohort studies, if associated with both the exposure and the probability of occurrence of the event, can introduce bias in the estimates of interest. The aim of this study is to evaluate the impact of participation and its characteristics in longitudinal studies. A systematic review (MEDLINE, Scopus and Web of Science for articles describing the proportion of participation in the baseline of cohort studies was performed. Among the 2,964 initially identified, 50 were selected. The average proportion of participation was 64.7%. Using a meta-regression model with mixed effects, only age, year of baseline contact and study region (borderline were associated with participation. Considering the decrease in participation in recent years, and the cost of cohort studies, it is essential to gather information to assess the potential for non-participation, before committing resources. Finally, journals should require the presentation of this information in the papers.

  6. Life expectancies of South African adults starting antiretroviral treatment: collaborative analysis of cohort studies.

    Science.gov (United States)

    Johnson, Leigh F; Mossong, Joel; Dorrington, Rob E; Schomaker, Michael; Hoffmann, Christopher J; Keiser, Olivia; Fox, Matthew P; Wood, Robin; Prozesky, Hans; Giddy, Janet; Garone, Daniela Belen; Cornell, Morna; Egger, Matthias; Boulle, Andrew

    2013-01-01

    Few estimates exist of the life expectancy of HIV-positive adults receiving antiretroviral treatment (ART) in low- and middle-income countries. We aimed to estimate the life expectancy of patients starting ART in South Africa and compare it with that of HIV-negative adults. Data were collected from six South African ART cohorts. Analysis was restricted to 37,740 HIV-positive adults starting ART for the first time. Estimates of mortality were obtained by linking patient records to the national population register. Relative survival models were used to estimate the excess mortality attributable to HIV by age, for different baseline CD4 categories and different durations. Non-HIV mortality was estimated using a South African demographic model. The average life expectancy of men starting ART varied between 27.6 y (95% CI: 25.2-30.2) at age 20 y and 10.1 y (95% CI: 9.3-10.8) at age 60 y, while estimates for women at the same ages were substantially higher, at 36.8 y (95% CI: 34.0-39.7) and 14.4 y (95% CI: 13.3-15.3), respectively. The life expectancy of a 20-y-old woman was 43.1 y (95% CI: 40.1-46.0) if her baseline CD4 count was ≥ 200 cells/µl, compared to 29.5 y (95% CI: 26.2-33.0) if her baseline CD4 count was <50 cells/µl. Life expectancies of patients with baseline CD4 counts ≥ 200 cells/µl were between 70% and 86% of those in HIV-negative adults of the same age and sex, and life expectancies were increased by 15%-20% in patients who had survived 2 y after starting ART. However, the analysis was limited by a lack of mortality data at longer durations. South African HIV-positive adults can have a near-normal life expectancy, provided that they start ART before their CD4 count drops below 200 cells/µl. These findings demonstrate that the near-normal life expectancies of HIV-positive individuals receiving ART in high-income countries can apply to low- and middle-income countries as well. Please see later in the article for the Editors' Summary.

  7. Life expectancies of South African adults starting antiretroviral treatment: collaborative analysis of cohort studies.

    Directory of Open Access Journals (Sweden)

    Leigh F Johnson

    Full Text Available Few estimates exist of the life expectancy of HIV-positive adults receiving antiretroviral treatment (ART in low- and middle-income countries. We aimed to estimate the life expectancy of patients starting ART in South Africa and compare it with that of HIV-negative adults.Data were collected from six South African ART cohorts. Analysis was restricted to 37,740 HIV-positive adults starting ART for the first time. Estimates of mortality were obtained by linking patient records to the national population register. Relative survival models were used to estimate the excess mortality attributable to HIV by age, for different baseline CD4 categories and different durations. Non-HIV mortality was estimated using a South African demographic model. The average life expectancy of men starting ART varied between 27.6 y (95% CI: 25.2-30.2 at age 20 y and 10.1 y (95% CI: 9.3-10.8 at age 60 y, while estimates for women at the same ages were substantially higher, at 36.8 y (95% CI: 34.0-39.7 and 14.4 y (95% CI: 13.3-15.3, respectively. The life expectancy of a 20-y-old woman was 43.1 y (95% CI: 40.1-46.0 if her baseline CD4 count was ≥ 200 cells/µl, compared to 29.5 y (95% CI: 26.2-33.0 if her baseline CD4 count was <50 cells/µl. Life expectancies of patients with baseline CD4 counts ≥ 200 cells/µl were between 70% and 86% of those in HIV-negative adults of the same age and sex, and life expectancies were increased by 15%-20% in patients who had survived 2 y after starting ART. However, the analysis was limited by a lack of mortality data at longer durations.South African HIV-positive adults can have a near-normal life expectancy, provided that they start ART before their CD4 count drops below 200 cells/µl. These findings demonstrate that the near-normal life expectancies of HIV-positive individuals receiving ART in high-income countries can apply to low- and middle-income countries as well. Please see later in the article for the Editors' Summary.

  8. Analysis and prediction of Multiple-Site Damage (MSD) fatigue crack growth

    Science.gov (United States)

    Dawicke, D. S.; Newman, J. C., Jr.

    1992-08-01

    A technique was developed to calculate the stress intensity factor for multiple interacting cracks. The analysis was verified through comparison with accepted methods of calculating stress intensity factors. The technique was incorporated into a fatigue crack growth prediction model and used to predict the fatigue crack growth life for multiple-site damage (MSD). The analysis was verified through comparison with experiments conducted on uniaxially loaded flat panels with multiple cracks. Configuration with nearly equal and unequal crack distribution were examined. The fatigue crack growth predictions agreed within 20 percent of the experimental lives for all crack configurations considered.

  9. Analysis and prediction of Multiple-Site Damage (MSD) fatigue crack growth

    Science.gov (United States)

    Dawicke, D. S.; Newman, J. C., Jr.

    1992-01-01

    A technique was developed to calculate the stress intensity factor for multiple interacting cracks. The analysis was verified through comparison with accepted methods of calculating stress intensity factors. The technique was incorporated into a fatigue crack growth prediction model and used to predict the fatigue crack growth life for multiple-site damage (MSD). The analysis was verified through comparison with experiments conducted on uniaxially loaded flat panels with multiple cracks. Configuration with nearly equal and unequal crack distribution were examined. The fatigue crack growth predictions agreed within 20 percent of the experimental lives for all crack configurations considered.

  10. The multiple imputation method: a case study involving secondary data analysis.

    Science.gov (United States)

    Walani, Salimah R; Cleland, Charles M

    2015-05-01

    To illustrate with the example of a secondary data analysis study the use of the multiple imputation method to replace missing data. Most large public datasets have missing data, which need to be handled by researchers conducting secondary data analysis studies. Multiple imputation is a technique widely used to replace missing values while preserving the sample size and sampling variability of the data. The 2004 National Sample Survey of Registered Nurses. The authors created a model to impute missing values using the chained equation method. They used imputation diagnostics procedures and conducted regression analysis of imputed data to determine the differences between the log hourly wages of internationally educated and US-educated registered nurses. The authors used multiple imputation procedures to replace missing values in a large dataset with 29,059 observations. Five multiple imputed datasets were created. Imputation diagnostics using time series and density plots showed that imputation was successful. The authors also present an example of the use of multiple imputed datasets to conduct regression analysis to answer a substantive research question. Multiple imputation is a powerful technique for imputing missing values in large datasets while preserving the sample size and variance of the data. Even though the chained equation method involves complex statistical computations, recent innovations in software and computation have made it possible for researchers to conduct this technique on large datasets. The authors recommend nurse researchers use multiple imputation methods for handling missing data to improve the statistical power and external validity of their studies.

  11. Plasma proteome analysis in patients with pulmonary arterial hypertension: an observational cohort study.

    Science.gov (United States)

    Rhodes, Christopher J; Wharton, John; Ghataorhe, Pavandeep; Watson, Geoffrey; Girerd, Barbara; Howard, Luke S; Gibbs, J Simon R; Condliffe, Robin; Elliot, Charles A; Kiely, David G; Simonneau, Gerald; Montani, David; Sitbon, Olivier; Gall, Henning; Schermuly, Ralph T; Ghofrani, H Ardeschir; Lawrie, Allan; Humbert, Marc; Wilkins, Martin R

    2017-09-01

    Idiopathic and heritable pulmonary arterial hypertension form a rare but molecularly heterogeneous disease group. We aimed to measure and validate differences in plasma concentrations of proteins that are associated with survival in patients with idiopathic or heritable pulmonary arterial hypertension to improve risk stratification. In this observational cohort study, we enrolled patients with idiopathic or heritable pulmonary arterial hypertension from London (UK; cohorts 1 and 2), Giessen (Germany; cohort 3), and Paris (France; cohort 4). Blood samples were collected at routine clinical appointment visits, clinical data were collected within 30 days of blood sampling, and biochemical data were collected within 7 days of blood sampling. We used an aptamer-based assay of 1129 plasma proteins, and patient clinical details were concealed to the technicians. We identified a panel of prognostic proteins, confirmed with alternative targeted assays, which we evaluated against the established prognostic risk equation for pulmonary arterial hypertension derived from the REVEAL registry. All-cause mortality was the primary endpoint. 20 proteins differentiated survivors and non-survivors in 143 consecutive patients with idiopathic or heritable pulmonary arterial hypertension with 2 years' follow-up (cohort 1) and in a further 75 patients with 2·5 years' follow-up (cohort 2). Nine proteins were both prognostic independent of plasma NT-proBNP concentrations and confirmed by targeted assays. The functions of these proteins relate to myocardial stress, inflammation, pulmonary vascular cellular dysfunction and structural dysregulation, iron status, and coagulation. A cutoff-based score using the panel of nine proteins provided prognostic information independent of the REVEAL equation, improving the C statistic from area under the curve 0·83 (for REVEAL risk score, 95% CI 0·77-0·89; parterial hypertension in cohort 3 (p=0·0133). The protein panel was validated in 93 patients

  12. Cohort description

    DEFF Research Database (Denmark)

    Dantoft, Thomas Meinertz; Ebstrup, Jeanette Frost; Linneberg, Allan

    2017-01-01

    -76 years from the general population examined from 2011 to 2015. The survey comprises screening questionnaires for five types of FSS, ie, fibromyalgia, whiplash-associated disorder, multiple chemical sensitivity, irritable bowel syndrome, and chronic fatigue syndrome, and for the unifying diagnostic......The Danish study of Functional Disorders (DanFunD) cohort was initiated to outline the epidemiology of functional somatic syndromes (FSS) and is the first larger coordinated epidemiological study focusing exclusively on FSS. FSS are prevalent in all medical settings and can be defined as syndromes...... category of bodily distress syndrome. Additional data included a telephone-based diagnostic interview assessment for FSS, questionnaires on physical and mental health, personality traits, lifestyle, use of health care services and social factors, and a physical examination with measures...

  13. Multiplication factor versus regression analysis in stature estimation from hand and foot dimensions.

    Science.gov (United States)

    Krishan, Kewal; Kanchan, Tanuj; Sharma, Abhilasha

    2012-05-01

    Estimation of stature is an important parameter in identification of human remains in forensic examinations. The present study is aimed to compare the reliability and accuracy of stature estimation and to demonstrate the variability in estimated stature and actual stature using multiplication factor and regression analysis methods. The study is based on a sample of 246 subjects (123 males and 123 females) from North India aged between 17 and 20 years. Four anthropometric measurements; hand length, hand breadth, foot length and foot breadth taken on the left side in each subject were included in the study. Stature was measured using standard anthropometric techniques. Multiplication factors were calculated and linear regression models were derived for estimation of stature from hand and foot dimensions. Derived multiplication factors and regression formula were applied to the hand and foot measurements in the study sample. The estimated stature from the multiplication factors and regression analysis was compared with the actual stature to find the error in estimated stature. The results indicate that the range of error in estimation of stature from regression analysis method is less than that of multiplication factor method thus, confirming that the regression analysis method is better than multiplication factor analysis in stature estimation. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  14. Low cigarette consumption and risk of coronary heart disease and stroke: meta-analysis of 141 cohort studies in 55 study reports

    Science.gov (United States)

    Morris, Joan K; Boniface, Sadie; Tang, Jin-Ling; Milenković, Dušan

    2018-01-01

    Abstract Objective To use the relation between cigarette consumption and cardiovascular disease to quantify the risk of coronary heart disease and stroke for light smoking (one to five cigarettes/day). Design Systematic review and meta-analysis. Data sources Medline 1946 to May 2015, with manual searches of references. Eligibility criteria for selecting studies Prospective cohort studies with at least 50 events, reporting hazard ratios or relative risks (both hereafter referred to as relative risk) compared with never smokers or age specific incidence in relation to risk of coronary heart disease or stroke. Data extraction/synthesis MOOSE guidelines were followed. For each study, the relative risk was estimated for smoking one, five, or 20 cigarettes per day by using regression modelling between risk and cigarette consumption. Relative risks were adjusted for at least age and often additional confounders. The main measure was the excess relative risk for smoking one cigarette per day (RR1_per_day−1) expressed as a proportion of that for smoking 20 cigarettes per day (RR20_per_day−1), expected to be about 5% assuming a linear relation between risk and consumption (as seen with lung cancer). The relative risks for one, five, and 20 cigarettes per day were also pooled across all studies in a random effects meta-analysis. Separate analyses were done for each combination of sex and disorder. Results The meta-analysis included 55 publications containing 141 cohort studies. Among men, the pooled relative risk for coronary heart disease was 1.48 for smoking one cigarette per day and 2.04 for 20 cigarettes per day, using all studies, but 1.74 and 2.27 among studies in which the relative risk had been adjusted for multiple confounders. Among women, the pooled relative risks were 1.57 and 2.84 for one and 20 cigarettes per day (or 2.19 and 3.95 using relative risks adjusted for multiple factors). Men who smoked one cigarette per day had 46% of the excess relative risk for

  15. Anonymous non-response analysis in the ABCD cohort study enabled by probabilistic record linkage

    NARCIS (Netherlands)

    Tromp, M.; van Eijsden, M.; Ravelli, A. C. J.; Bonsel, G. J.

    2009-01-01

    Selective non-response is an important threat to study validity as it can lead to selection bias. The Amsterdam Born Children and their Development study (ABCD-study) is a large cohort study addressing the relationship between life style, psychological conditions, nutrition and sociodemographic

  16. Cohort change and the diffusion of environmental concern: A cross-national analysis.

    Science.gov (United States)

    Nawrotzki, Raphael J; Pampel, Fred C

    2013-09-01

    This study explores value change across cohorts for a multinational population sample. Employing a diffusion-of-innovations approach, we combine competing theories predicting the relationship between socio-economic status (SES) and environmentalism: post-materialism and affluence theories, and global environmentalism theory. The diffusion argument suggests that high-SES groups first adopt pro-environmental views, but as time passes by, environmentalism diffuses to lower-SES groups. We test the diffusion argument using a sample of 18 countries for two waves (years 1993 and 2000) from the International Social Survey Project (ISSP). Cross-classified multilevel modeling allows us to identify a non-linear interaction between cohort and education, our core measure of SES, in predicting environmental concern, while controlling for age and period. We find support for the diffusion argument and demonstrate that the positive effect of education on environmental concern first increases among older cohorts, then starts to level off until a bend-point is reached for individuals born around 1940 and becomes progressively weaker for younger cohorts.

  17. Using the entire history in the analysis of nested case cohort samples.

    Science.gov (United States)

    Rivera, C L; Lumley, T

    2016-08-15

    Countermatching designs can provide more efficient estimates than simple matching or case-cohort designs in certain situations such as when good surrogate variables for an exposure of interest are available. We extend pseudolikelihood estimation for the Cox model under countermatching designs to models where time-varying covariates are considered. We also implement pseudolikelihood with calibrated weights to improve efficiency in nested case-control designs in the presence of time-varying variables. A simulation study is carried out, which considers four different scenarios including a binary time-dependent variable, a continuous time-dependent variable, and the case including interactions in each. Simulation results show that pseudolikelihood with calibrated weights under countermatching offers large gains in efficiency if compared to case-cohort. Pseudolikelihood with calibrated weights yielded more efficient estimators than pseudolikelihood estimators. Additionally, estimators were more efficient under countermatching than under case-cohort for the situations considered. The methods are illustrated using the Colorado Plateau uranium miners cohort. Furthermore, we present a general method to generate survival times with time-varying covariates. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  18. Dairy foods, calcium, and colorectal cancer: A pooled analysis of 10 cohort studies

    NARCIS (Netherlands)

    Cho, E.; Smith-Warner, S.A.; Spiegelman, D.; Beeson, W.L.; Brandt, P.A. van den; Colditz, G.A.; Folsom, A.R.; Fraser, G.E.; Freudenheim, J.L.; Giovannucci, E.; Goldbohm, R.A.; Graham, S.; Miller, A.B.; Pietinen, P.; Potter, J.D.; Rohan, T.E.; Terry, P.; Toniolo, P.; Virtanen, M.J.; Willet, W.C.; Wolk, A.; Wu, K.; Yaun, S.-S.; Zeleniuch-Jacquotte, A.; Hunter, D.J.

    2004-01-01

    Background: Studies in animals have suggested that calcium may reduce the risk of colorectal cancer. However, results from epidemiologic studies of intake of calcium or dairy foods and colorectal cancer risk have been inconclusive. Methods: We pooled the primary data from 10 cohort studies in five

  19. Cohort change and the diffusion of environmental concern: A cross-national analysis

    Science.gov (United States)

    Nawrotzki, Raphael J.; Pampel, Fred C.

    2013-01-01

    This study explores value change across cohorts for a multinational population sample. Employing a diffusion-of-innovations approach, we combine competing theories predicting the relationship between socio-economic status (SES) and environmentalism: post-materialism and affluence theories, and global environmentalism theory. The diffusion argument suggests that high-SES groups first adopt pro-environmental views, but as time passes by, environmentalism diffuses to lower-SES groups. We test the diffusion argument using a sample of 18 countries for two waves (years 1993 and 2000) from the International Social Survey Project (ISSP). Cross-classified multilevel modeling allows us to identify a non-linear interaction between cohort and education, our core measure of SES, in predicting environmental concern, while controlling for age and period. We find support for the diffusion argument and demonstrate that the positive effect of education on environmental concern first increases among older cohorts, then starts to level off until a bend-point is reached for individuals born around 1940 and becomes progressively weaker for younger cohorts. PMID:24179313

  20. Life-course and cohort trajectories of mental health in the UK, 1991-2008--a multilevel age-period-cohort analysis.

    Science.gov (United States)

    Bell, Andrew

    2014-11-01

    There is ongoing debate regarding the shape of life-course trajectories in mental health. Many argue the relationship is U-shaped, with mental health declining with age to mid-life, then improving. However, I argue that these models are beset by the age-period-cohort (APC) identification problem, whereby age, cohort and year of measurement are exactly collinear and their effects cannot be meaningfully separated. This means an apparent life-course effect could be explained by cohorts. This paper critiques two sets of literature: the substantive literature regarding life-course trajectories in mental health, and the methodological literature that claims erroneously to have 'solved' the APC identification problem statistically (e.g. using Yang and Land's Hierarchical APC-HAPC-model). I then use a variant of the HAPC model, making strong but justified assumptions that allow the modelling of life-course trajectories in mental health (measured by the General Health Questionnaire) net of any cohort effects, using data from the British Household Panel Survey, 1991-2008. The model additionally employs a complex multilevel structure that allows the relative importance of spatial (households, local authority districts) and temporal (periods, cohorts) levels to be assessed. Mental health is found to increase throughout the life-course; this slows at mid-life before worsening again into old age, but there is no evidence of a U-shape--I argue that such findings result from confounding with cohort processes (whereby more recent cohorts have generally worse mental health). Other covariates were also evaluated; income, smoking, education, social class, urbanity, ethnicity, gender and marriage were all related to mental health, with the latter two in particular affecting life-course and cohort trajectories. The paper shows the importance of understanding APC in life-course research generally, and mental health research in particular. Copyright © 2014 Elsevier Ltd. All rights

  1. Changing Attitudes Toward Euthanasia and Suicide for Terminally Ill Persons, 1977 to 2016: An Age-Period-Cohort Analysis.

    Science.gov (United States)

    Attell, Brandon K

    2017-01-01

    Several longitudinal studies show that over time the American public has become more approving of euthanasia and suicide for terminally ill persons. Yet, these previous findings are limited because they derive from biased estimates of disaggregated hierarchical data. Using insights from life course sociological theory and cross-classified logistic regression models, I better account for this liberalization process by disentangling the age, period, and cohort effects that contribute to longitudinal changes in these attitudes. The results of the analysis point toward a continued liberalization of both attitudes over time, although the magnitude of change was greater for suicide compared with euthanasia. More fluctuation in the probability of supporting both measures was exhibited for the age and period effects over the cohort effects. In addition, age-based differences in supporting both measures were found between men and women and various religious affiliations.

  2. Viral Determinants of FeLV Infection and Pathogenesis: Lessons Learned from Analysis of a Natural Cohort

    Directory of Open Access Journals (Sweden)

    Laura S. Levy

    2011-09-01

    Full Text Available Detailed analysis has been performed over many years of a geographic and temporal cohort of cats naturally infected with feline leukemia virus (FeLV. Molecular analysis of FeLV present in the diseased tissues and application of those viruses to experimental systems has revealed unique isolates with distinctive disease potential, previously uncharacterized virus-receptor interactions, information about the role of recombinant viruses in disease induction, and novel viral and cellular oncogenes implicated in pathogenesis, among other findings. The studies have contributed to an understanding of the selective forces that lead to predominance of distinctive FeLV isolates and disease outcomes in a natural population.

  3. Estimation of lung tumor position from multiple anatomical features on 4D-CT using multiple regression analysis.

    Science.gov (United States)

    Ono, Tomohiro; Nakamura, Mitsuhiro; Hirose, Yoshinori; Kitsuda, Kenji; Ono, Yuka; Ishigaki, Takashi; Hiraoka, Masahiro

    2017-09-01

    To estimate the lung tumor position from multiple anatomical features on four-dimensional computed tomography (4D-CT) data sets using single regression analysis (SRA) and multiple regression analysis (MRA) approach and evaluate an impact of the approach on internal target volume (ITV) for stereotactic body radiotherapy (SBRT) of the lung. Eleven consecutive lung cancer patients (12 cases) underwent 4D-CT scanning. The three-dimensional (3D) lung tumor motion exceeded 5 mm. The 3D tumor position and anatomical features, including lung volume, diaphragm, abdominal wall, and chest wall positions, were measured on 4D-CT images. The tumor position was estimated by SRA using each anatomical feature and MRA using all anatomical features. The difference between the actual and estimated tumor positions was defined as the root-mean-square error (RMSE). A standard partial regression coefficient for the MRA was evaluated. The 3D lung tumor position showed a high correlation with the lung volume (R = 0.92 ± 0.10). Additionally, ITVs derived from SRA and MRA approaches were compared with ITV derived from contouring gross tumor volumes on all 10 phases of the 4D-CT (conventional ITV). The RMSE of the SRA was within 3.7 mm in all directions. Also, the RMSE of the MRA was within 1.6 mm in all directions. The standard partial regression coefficient for the lung volume was the largest and had the most influence on the estimated tumor position. Compared with conventional ITV, average percentage decrease of ITV were 31.9% and 38.3% using SRA and MRA approaches, respectively. The estimation accuracy of lung tumor position was improved by the MRA approach, which provided smaller ITV than conventional ITV. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  4. Sleep duration and obesity in children: A systematic review and meta-analysis of prospective cohort studies.

    Science.gov (United States)

    Li, Lian; Zhang, Shuang; Huang, Yubei; Chen, Kexin

    2017-04-01

    Childhood obesity is a major public problem worldwide, and sleep duration may be associated with childhood obesity. We conducted a systematic review and meta-analysis of prospective cohort studies to estimate the associations between sleep duration and obesity/body mass index (BMI) in children. PubMed, Embase and the Cochrane Library were searched. For the meta-analysis, the pooled relative risk (RR) and 95% confidence intervals (CI) were estimated to reveal the association between short sleep duration and obesity. For the review, the outcomes focused on BMI change or subsequent BMI status. A total of 12 studies (15 populations) met the criteria for inclusion in the meta-analysis. Short sleep duration was significantly associated with obesity (RR: 1.45; 95% CI: 1.14-1.85). After excluding two cohorts that substantially affected the heterogeneity, the pooled results remained significant (RR: 1.30; 95% CI: 1.20-1.42), and the association was not substantially altered in the subgroup analysis. In addition, we summarised 24 studies that met the criteria for our review of the relationship between sleeping and BMI. The present meta-analysis indicated that short sleep duration increased the risk of childhood obesity. Public health efforts that encourage children to have sufficient sleep time may be important in combating obesity. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  5. Ca analysis: an Excel based program for the analysis of intracellular calcium transients including multiple, simultaneous regression analysis.

    Science.gov (United States)

    Greensmith, David J

    2014-01-01

    Here I present an Excel based program for the analysis of intracellular Ca transients recorded using fluorescent indicators. The program can perform all the necessary steps which convert recorded raw voltage changes into meaningful physiological information. The program performs two fundamental processes. (1) It can prepare the raw signal by several methods. (2) It can then be used to analyze the prepared data to provide information such as absolute intracellular Ca levels. Also, the rates of change of Ca can be measured using multiple, simultaneous regression analysis. I demonstrate that this program performs equally well as commercially available software, but has numerous advantages, namely creating a simplified, self-contained analysis workflow. Copyright © 2013 The Author. Published by Elsevier Ireland Ltd.. All rights reserved.

  6. Links between Bloom's Taxonomy and Gardener's Multiple Intelligences: The Issue of Textbook Analysis

    Science.gov (United States)

    Tabari, Mahmoud Abdi; Tabari, Iman Abdi

    2015-01-01

    The major thrust of this research was to investigate the cognitive aspect of the high school textbooks and interchange series, due to their extensive use, through content analysis based on Bloom's taxonomy and Gardner's Multiple Intelligences (MI). This study embraced two perspectives in a grid in order to broaden and deepen the analysis by…

  7. Prognostic Classification Factors Associated With Development of Multiple Autoantibodies, Dysglycemia, and Type 1 Diabetes-A Recursive Partitioning Analysis.

    Science.gov (United States)

    Xu, Ping; Krischer, Jeffrey P

    2016-06-01

    To define prognostic classification factors associated with the progression from single to multiple autoantibodies, multiple autoantibodies to dysglycemia, and dysglycemia to type 1 diabetes onset in relatives of individuals with type 1 diabetes. Three distinct cohorts of subjects from the Type 1 Diabetes TrialNet Pathway to Prevention Study were investigated separately. A recursive partitioning analysis (RPA) was used to determine the risk classes. Clinical characteristics, including genotype, antibody titers, and metabolic markers were analyzed. Age and GAD65 autoantibody (GAD65Ab) titers defined three risk classes for progression from single to multiple autoantibodies. The 5-year risk was 11% for those subjects >16 years of age with low GAD65Ab titers, 29% for those ≤16 years of age with low GAD65Ab titers, and 45% for those subjects with high GAD65Ab titers regardless of age. Progression to dysglycemia was associated with islet antigen 2 Ab titers, and 2-h glucose and fasting C-peptide levels. The 5-year risk is 28%, 39%, and 51% for respective risk classes defined by the three predictors. Progression to type 1 diabetes was associated with the number of positive autoantibodies, peak C-peptide level, HbA1c level, and age. Four risk classes defined by RPA had a 5-year risk of 9%, 33%, 62%, and 80%, respectively. The use of RPA offered a new classification approach that could predict the timing of transitions from one preclinical stage to the next in the development of type 1 diabetes. Using these RPA classes, new prevention techniques can be tailored based on the individual prognostic risk characteristics at different preclinical stages. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  8. Prognostic Classification Factors Associated With Development of Multiple Autoantibodies, Dysglycemia, and Type 1 Diabetes—A Recursive Partitioning Analysis

    Science.gov (United States)

    Krischer, Jeffrey P.

    2016-01-01

    OBJECTIVE To define prognostic classification factors associated with the progression from single to multiple autoantibodies, multiple autoantibodies to dysglycemia, and dysglycemia to type 1 diabetes onset in relatives of individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS Three distinct cohorts of subjects from the Type 1 Diabetes TrialNet Pathway to Prevention Study were investigated separately. A recursive partitioning analysis (RPA) was used to determine the risk classes. Clinical characteristics, including genotype, antibody titers, and metabolic markers were analyzed. RESULTS Age and GAD65 autoantibody (GAD65Ab) titers defined three risk classes for progression from single to multiple autoantibodies. The 5-year risk was 11% for those subjects >16 years of age with low GAD65Ab titers, 29% for those ≤16 years of age with low GAD65Ab titers, and 45% for those subjects with high GAD65Ab titers regardless of age. Progression to dysglycemia was associated with islet antigen 2 Ab titers, and 2-h glucose and fasting C-peptide levels. The 5-year risk is 28%, 39%, and 51% for respective risk classes defined by the three predictors. Progression to type 1 diabetes was associated with the number of positive autoantibodies, peak C-peptide level, HbA1c level, and age. Four risk classes defined by RPA had a 5-year risk of 9%, 33%, 62%, and 80%, respectively. CONCLUSIONS The use of RPA offered a new classification approach that could predict the timing of transitions from one preclinical stage to the next in the development of type 1 diabetes. Using these RPA classes, new prevention techniques can be tailored based on the individual prognostic risk characteristics at different preclinical stages. PMID:27208341

  9. Cannabis and intractable chronic pain: an explorative retrospective analysis of Italian cohort of 614 patients.

    Science.gov (United States)

    Fanelli, Guido; De Carolis, Giuliano; Leonardi, Claudio; Longobardi, Adele; Sarli, Ennio; Allegri, Massimo; Schatman, Michael E

    2017-01-01

    Despite growing interest in the therapeutic use of cannabis to manage chronic pain, only limited data that address these issues are available. In recent years, a number of nations have introduced specific laws to allow patients to use cannabis preparations to treat a variety of medical conditions. In 2015, the Italian government authorized the use of cannabis to treat several diseases, including chronic pain generally, spasticity in multiple sclerosis, cachexia and anorexia among AIDS and cancer patients, glaucoma, Tourette syndrome, and certain types of epilepsy. We present the first snapshot of the Italian experience with cannabis use for chronic pain over the initial year of its use. This is a retrospective case series analysis of all chronic pain patients treated with oral or vaporized cannabis in six hubs during the initial year following the approval of the new Italian law (December 2015 to November 2016). We evaluated routes of administration, types of cannabis products utilized, dosing, and effectiveness and safety of the treatment. As only one of the six centers has extensively used cannabinoids for intractable chronic pain (614 patients of 659), only the population from Azienda Ospedaliero Universitaria Pisana (Pisa) was considered. Cannabis tea was the primary mode of delivery, and in almost all cases, it was used in association with all the other pain treatments. Initial and follow-up cannabinoid concentrations were found to vary considerably. At initial follow-up, 76.2% of patients continued the treatment, and <15% stopped the treatment due to side effects (none of which were severe). We present the first analysis of Italian clinical practice of the use of cannabinoids for a large variety of chronic pain syndromes. From this initial snapshot, we determined that the treatment seems to be effective and safe, although more data and subsequent trials are needed to better investigate its ideal clinical indication.

  10. Cannabis and intractable chronic pain: an explorative retrospective analysis of Italian cohort of 614 patients

    Science.gov (United States)

    Fanelli, Guido; De Carolis, Giuliano; Leonardi, Claudio; Longobardi, Adele; Sarli, Ennio; Allegri, Massimo; Schatman, Michael E

    2017-01-01

    Background Despite growing interest in the therapeutic use of cannabis to manage chronic pain, only limited data that address these issues are available. In recent years, a number of nations have introduced specific laws to allow patients to use cannabis preparations to treat a variety of medical conditions. In 2015, the Italian government authorized the use of cannabis to treat several diseases, including chronic pain generally, spasticity in multiple sclerosis, cachexia and anorexia among AIDS and cancer patients, glaucoma, Tourette syndrome, and certain types of epilepsy. We present the first snapshot of the Italian experience with cannabis use for chronic pain over the initial year of its use. Methods This is a retrospective case series analysis of all chronic pain patients treated with oral or vaporized cannabis in six hubs during the initial year following the approval of the new Italian law (December 2015 to November 2016). We evaluated routes of administration, types of cannabis products utilized, dosing, and effectiveness and safety of the treatment. Results As only one of the six centers has extensively used cannabinoids for intractable chronic pain (614 patients of 659), only the population from Azienda Ospedaliero Universitaria Pisana (Pisa) was considered. Cannabis tea was the primary mode of delivery, and in almost all cases, it was used in association with all the other pain treatments. Initial and follow-up cannabinoid concentrations were found to vary considerably. At initial follow-up, 76.2% of patients continued the treatment, and <15% stopped the treatment due to side effects (none of which were severe). Conclusion We present the first analysis of Italian clinical practice of the use of cannabinoids for a large variety of chronic pain syndromes. From this initial snapshot, we determined that the treatment seems to be effective and safe, although more data and subsequent trials are needed to better investigate its ideal clinical indication. PMID

  11. Seismic response analysis of structural system subjected to multiple support excitation

    International Nuclear Information System (INIS)

    Wu, R.W.; Hussain, F.A.; Liu, L.K.

    1978-01-01

    In the seismic analysis of a multiply supported structural system subjected to nonuniform excitations at each support point, the single response spectrum, the time history, and the multiple response spectrum are the three commonly employed methods. In the present paper the three methods are developed, evaluated, and the limitations and advantages of each method assessed. A numerical example has been carried out for a typical piping system. Considerably smaller responses have been predicted by the time history method than that by the single response spectrum method. This is mainly due to the fact that the phase and amplitude relations between the support excitations are faithfully retained in the time history method. The multiple response spectrum prediction has been observed to compare favourably with the time history method prediction. Based on the present evaluation, the multiple response spectrum method is the most efficient method for seismic response analysis of structural systems subjected to multiple support excitation. (Auth.)

  12. Association Between Arterial Hyperoxia and Outcome in Subsets of Critical Illness: A Systematic Review, Meta-Analysis, and Meta-Regression of Cohort Studies.

    Science.gov (United States)

    Helmerhorst, Hendrik J F; Roos-Blom, Marie-José; van Westerloo, David J; de Jonge, Evert

    2015-07-01

    Oxygen is vital during critical illness, but hyperoxia may harm patients. Our aim was to systematically evaluate the methodology and findings of cohort studies investigating the effects of hyperoxia in critically ill adults. A meta-analysis and meta-regression analysis of cohort studies published between 2008 and 2015 was conducted. Electronic databases of MEDLINE, EMBASE, and Web of Science were systematically searched for the keywords hyperoxia and mortality or outcome. Publications assessing the effect of arterial hyperoxia on outcome in critically ill adults (≥ 18 yr) admitted to critical care units were eligible. We excluded studies in patients with chronic obstructive pulmonary disease, extracorporeal life support or hyperbaric oxygen therapy, and animal studies. Due to a lack of data, no studies dedicated to patients with acute lung injury, sepsis, shock, or multiple trauma could be included. Studies were included independent of admission diagnosis and definition of hyperoxia. The primary outcome measure was in-hospital mortality, and results were stratified for relevant subgroups (cardiac arrest, traumatic brain injury, stroke, post-cardiac surgery, and any mechanical ventilation). The effects of arterial oxygenation on functional outcome, long-term mortality, and discharge variables were studied as secondary outcomes. Twenty-four studies were included of which five studies were only for a subset of the analyses. Nineteen studies were pooled for meta-analyses and showed that arterial hyperoxia during admission increases hospital mortality: adjusted odds ratio, 1.21 (95% CI, 1.08-1.37) (p = 0.001). Functional outcome measures were diverse and generally showed a more favorable outcome for normoxia. In various subsets of critically ill patients, arterial hyperoxia was associated with poor hospital outcome. Considering the substantial heterogeneity of included studies and the lack of a clinical definition, more evidence is needed to provide optimal oxygen

  13. The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis.

    Science.gov (United States)

    Abbott, T E F; Ahmad, T; Phull, M K; Fowler, A J; Hewson, R; Biccard, B M; Chew, M S; Gillies, M; Pearse, R M

    2018-01-01

    The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32-0.77); P<0.01], but no difference in complication rates [OR 1.02 (0.88-1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62-0.92); P<0.01; I 2 =87%] and reduced complication rates [OR 0.73 (0.61-0.88); P<0.01; I 2 =89%). Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine. Copyright © 2017 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.

  14. Materialism across the life span: An age-period-cohort analysis.

    Science.gov (United States)

    Jaspers, Esther D T; Pieters, Rik G M

    2016-09-01

    This research examined the development of materialism across the life span. Two initial studies revealed that (a) lay beliefs were that materialism declines with age and (b) previous research findings also implied a modest, negative relationship between age and materialism. Yet, previous research has considered age only as a linear control variable, thereby precluding the possibility of more intricate relationships between age and materialism. Moreover, prior studies have relied on cross-sectional data and thus confound age and cohort effects. To improve on this, the main study used longitudinal data from 8 waves spanning 9 years of over 4,200 individuals (16 to 90 years) to examine age effects on materialism while controlling for cohort and period effects. Using a multivariate multilevel latent growth model, it found that materialism followed a curvilinear trajectory across the life span, with the lowest levels at middle age and higher levels before and after that. Thus, in contrast to lay beliefs, materialism increased in older age. Moreover, age effects on materialism differed markedly between 3 core themes of materialism: acquisition centrality, possession-defined success, and acquisition as the pursuit of happiness. In particular, acquisition centrality and possession-defined success were higher at younger and older age. Independent of these age effects, older birth cohorts were oriented more toward possession-defined success, whereas younger birth cohorts were oriented more toward acquisition centrality. The economic downturn since 2008 led to a decrease in acquisition as the pursuit of happiness and in desires for personal growth, but to an increase in desires for achievement. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  15. Cohort change and the diffusion of environmental concern: A cross-national analysis

    OpenAIRE

    Nawrotzki, Raphael J.; Pampel, Fred C.

    2012-01-01

    This study explores value change across cohorts for a multinational population sample. Employing a diffusion-of-innovations approach, we combine competing theories predicting the relationship between socio-economic status (SES) and environmentalism: post-materialism and affluence theories, and global environmentalism theory. The diffusion argument suggests that high-SES groups first adopt pro-environmental views, but as time passes by, environmentalism diffuses to lower-SES groups. We test th...

  16. Modifiable Psychosocial Constructs Associated With Physical Activity Participation in People With Multiple Sclerosis: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Casey, Blathin; Coote, Susan; Shirazipour, Celina; Hannigan, Ailish; Motl, Robert; Martin Ginis, Kathleen; Latimer-Cheung, Amy

    2017-07-01

    To synthesize current knowledge of the modifiable psychosocial constructs associated with physical activity (PA) participation in people with multiple sclerosis. A search was conducted through October 2015 in 8 electronic databases: CINAHL, PubMed, SPORTDiscus, Web of Knowledge, MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and PsycINFO. Cohort and intervention studies were included if they (1) included an objective or subjective measure of PA; (2) measured at least 1 modifiable psychosocial construct; and (3) reported bivariate correlations (or these could be extracted) between the PA and psychosocial construct measures. A total of 13,867 articles were screened for inclusion, and 26 were included in the final analysis. Meta-analyses of correlations were conducted using the Hedges-Olkin method. Where a meta-analysis was not possible, results were reported descriptively. Meta-analyses indicated a pooled correlation coefficient between (1) objective PA and self-efficacy (n=7) of r=.30 (Pgoal-setting (n=5) of r=.44 (Pgoal-setting. However, there is a need to explore the associations between other constructs outside those reported in this review. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  17. Prognostic significance of focal lesions and diffuse infiltration on MRI for multiple myeloma: a meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, So-Yeon; Park, Hee-Jin [Sungkyunkwan University School of Medicine, Department of Radiology, Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Kim, Hyun-Jung [Korea University College of Medicine, Department of Preventive Medicine, Seoul (Korea, Republic of); Shin, Yu Ri [The Catholic University of Korea, Department of Radiology, Incheon St. Mary' s Hospital, College of Medicine, Seoul (Korea, Republic of); Lee, Yun-Gyoo; Oh, Suk Joong [Sungkyunkwan University School of Medicine, Division of Hematology and Oncology, Department of Internal Medicine, Kangbuk Samsung Hospital, Seoul (Korea, Republic of)

    2017-06-15

    MRI of bone marrow of the axial skeleton is recommended for evaluation of multiple myeloma. The impact of bone marrow involvement pattern on MRI for determining progression-free survival (PFS) and overall survival (OS) is not yet clear. We performed a meta-analysis of research on the prognostic significance of MRI patterns for OS and PFS using a random effects model. Databases searched without language restriction were MEDLINE, EMBASE, and the Cochrane Library (January 1976 to April 2014). Manual searches were also conducted. Of 10,953 citations identified in the original search, 10 cohort studies for a total of 2015 patients met the inclusion criteria. Nine of the 10 included studies are from three research groups. Pooled hazard ratios were 1.80 (95 % confidence interval [CI] 1.32-2.46; P < 0.001) for OS and 2.30 (95 % CI 1.65-3.20; P < 0.001) for PFS for focal lesions on MRI; and 1.70 (95 % CI 1.30-2.21; P < 0.001) for OS and 1.74 (95 % CI 1.07-2.85; P = 0.03) for PFS for diffuse infiltration on MRI. No significant heterogeneity was observed among studies. This meta-analysis demonstrated an association between focal lesions and diffuse infiltration and poor prognosis in this population. (orig.)

  18. Cohort Coefficients

    DEFF Research Database (Denmark)

    Kristensen, Gustav

    2013-01-01

    Cohorts are the aggregate of individuals who experience the same event within the same time interval. Cohorts can be based on people born in a given year, for example in 1940 or within a span of years, e.g. born in 1940-1944. The year of birth is here the defining event for cohorts. The health di...... differs between cohorts. This article focuses on the protective and detrimental cohort effect in relation to the risk of death from apoplexy. A dummy variable method is recommended to describe the changing cohort effect over a century....

  19. Fish intake and ovarian cancer risk: a meta-analysis of 15 case-control and cohort studies.

    Directory of Open Access Journals (Sweden)

    Pei-yue Jiang

    Full Text Available BACKGROUND: Previous epidemiological studies have shown that fish consumption may modify the risk of ovarian cancer. However, these studies yielded controversial results. The present meta-analysis was undertaken to evaluate the relationship between fish intake and ovarian cancer risk. METHODS: A literature search was carried out using Pubmed, Embase, and Cochrane Library Central database for all relevant studies up to August 2013. We pooled the relative risks (RR from individual studies using fixed-effect or random-effect model, and carried out heterogeneity and publication bias analyses. RESULTS: A total of 15 (ten case-control, and five cohort studies were included in the present meta-analysis, representing data for 889,033 female subjects and 6,087 ovarian cancer cases. We found that total fish intake was not significantly associated with the risk of ovarian cancer among cohort studies (RR = 1.04 95% CI [0.89, 1.22] as well as case-control studies (RR = 0.90, 95% CI [0.73,1.12]. There was no evidence of publication bias as suggested by Begg's test (P = 0.55 and Egger's test(P = 0.29. CONCLUSIONS: The present meta-analysis showed that total fish consumption was not significantly associated with the risk of ovarian cancer. Further analysis on different fish species and food preparation methods should be conducted in future studies.

  20. Chronic urinary tract infection and bladder carcinoma risk: a meta-analysis of case-control and cohort studies.

    Science.gov (United States)

    Akhtar, Saeed; Al-Shammari, Ahmad; Al-Abkal, Jarrah

    2018-02-05

    This meta-analysis of published case-control and cohort studies sought to quantify the magnitude and direction of association between chronic UTI (defined as the infection of the urinary tract that either does not respond to treatment or keeps recurring) and risk of bladder carcinoma (BCa) (i.e., including mainly urothelial carcinoma, squamous cell carcinoma or adenocarcinoma). A literature search was conducted using Medline, Embase, Ovid, Web of Science, Science Direct and Cochrane Library, which was supplemented with manual search of reference lists of the identified articles. Case-control and cohort studies examining UTI as a predictor of BCa risk published through June 2016 were eligible. Using random-effects models, odds ratios (OR) or relative risks (RR) from eligible studies were combined to synthesize summary effect estimates. The included studies were assessed for methodological quality and potential publication bias. Heterogeneity by study characteristics was examined by sub-group and meta-regression analyses. Eighteen case-control and three cohort studies published between 1963 and 2016 were eligible. Random-effects models showed that UTI was significantly associated with an increased BCa risk both in case-control studies (summary OR RE  = 2.33; 95% CI 1.86, 2.92) and cohort studies (summary RR RE  = 2.88; 95% CI 1.20, 6.89). The observed relationship of UTI with an increased BCa risk was independent of the study characteristics considered. No significant publication bias was detected. Chronic UTI was significantly and independently associated with an increased BCa risk. However, due to the presence of high between-study heterogeneity and inconsistent patterns of adjusted confounding effects, more data are needed to clarify the role of chronic UTI in causation of BCa and if established, prompt and effective treatment of UTI may minimize a substantial proportion of BCa risk.

  1. Less overdiagnosis of kidney cancer? an age-period-cohort analysis of incidence trends in 16 populations worldwide.

    Science.gov (United States)

    Znaor, Ariana; Laversanne, Mathieu; Bray, Freddie

    2017-09-01

    The increasing rates of kidney cancer incidence, reported in many populations globally, have been attributed both to increasing exposures to environmental risk factors, as well as increasing levels of incidental diagnosis due to widespread use of imaging. To better understand these trends, we examine long-term cancer registry data worldwide, focusing on the roles of birth cohort and calendar period, proxies for changes in risk factor prevalence and detection practice respectively. We used an augmented version of the Cancer Incidence in Five Continents series to analyze kidney cancer incidence rates 1978-2007 in 16 geographically representative populations worldwide by sex for ages 30-74, using age-period-cohort (APC) analysis. The full APC model provided the best fit to the data in most studied populations. While kidney cancer incidence rates have been increasing in successive generations born from the early twentieth century in most countries, equivalent period-specific rises were observed from the late-1970s, although these have subsequently stabilized in certain European countries (the Czech Republic, Lithuania, Finland, Spain) as well as Japan from the mid-1990s, and from the mid-2000s, in Colombia, Costa Rica and Australia. Our results indicate that the effects of both birth cohort and calendar period contribute to the international kidney cancer incidence trends. While cohort-specific increases may partly reflect the rising trends in obesity prevalence and the need for more effective primary prevention policies, the attenuations in period-specific increases (observed in 8 of the 16 populations) highlight a possible change in imaging practices that could lead to mitigation of overdiagnosis and overtreatment. © 2017 UICC.

  2. A cross sectional analysis of the role of the antimicrobial peptide cathelicidin in lung function impairment within the ALIVE cohort.

    Directory of Open Access Journals (Sweden)

    Allison A Lambert

    Full Text Available Vitamin D deficiency is associated with reduced lung function. Cathelicidin, an antimicrobial peptide regulated by vitamin D, plays a role within the innate immune system. The association of cathelicidin with lung function decrement and respiratory infection is undefined. We determined the independent relationship of cathelicidin with lung function.In a cross-sectional analysis of 650 participants in an urban observational cohort with high smoking prevalence, plasma 25(OH-vitamin D and cathelicidin levels were measured from stored samples obtained within 6 months of spirometry study visits. Multivariable linear regression was used to determine the independent association between low cathelicidin (defined as the lowest quartile of the cohort and absolute forced expiratory volume in 1 second (FEV1.The mean age of the cohort was 49 years; 91% were black, 35% female and 41% HIV-infected. Participants with low cathelicidin had a 183 mL lower FEV1 compared to higher cathelicidin (p = 0.009; this relationship was maintained (115 ml lower; p = 0.035 after adjusting for demographics, BMI, and smoking. Neither HIV serostatus, heavy smoking history, nor 25(OH-vitamin D levels were associated with cathelicidin levels. Participants with low cathelicidin had a greater prevalence of prior bacterial pneumonia (21% versus 14%; p = 0.047. Inclusion of pneumonia in adjusted models did not substantially reduce the FEV1 decrement observed with low cathelicidin (104 mL lower FEV1; p = 0.05. Lung function decrements associated with low cathelicidin were greatest among individuals with lower 25(OH-vitamin D levels.In a cohort at risk for airflow obstruction, low cathelicidin was independently associated with lower FEV1. These clinical data support a mechanistic link between 25(OH-vitamin D deficiency and lung function impairment, independent of pneumonia risk.

  3. Does vagotomy protect against multiple sclerosis?

    Science.gov (United States)

    Sundbøll, Jens; Horváth-Puhó, Erzsébet; Adelborg, Kasper; Svensson, Elisabeth

    2017-07-01

    To examine the association between vagotomy and multiple sclerosis. We conducted a matched cohort study of all patients who underwent truncal or super-selective vagotomy and a comparison cohort, by linking Danish population-based medical registries (1977-1995). Hazard ratios (HRs) for multiple sclerosis, adjusting for potential confounders were computed by means of Cox regression analysis. Median age of multiple sclerosis onset corresponded to late onset multiple sclerosis. No association with multiple sclerosis was observed for truncal vagotomy (0-37 year adjusted HR=0.91, 95% confidence interval [CI]: 0.48-1.74) or super-selective vagotomy (0-37 year adjusted HR=1.28, 95% CI: 0.79-2.09) compared with the general population. We found no association between vagotomy and later risk of late onset multiple sclerosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. A P-value model for theoretical power analysis and its applications in multiple testing procedures

    Directory of Open Access Journals (Sweden)

    Fengqing Zhang

    2016-10-01

    Full Text Available Abstract Background Power analysis is a critical aspect of the design of experiments to detect an effect of a given size. When multiple hypotheses are tested simultaneously, multiplicity adjustments to p-values should be taken into account in power analysis. There are a limited number of studies on power analysis in multiple testing procedures. For some methods, the theoretical analysis is difficult and extensive numerical simulations are often needed, while other methods oversimplify the information under the alternative hypothesis. To this end, this paper aims to develop a new statistical model for power analysis in multiple testing procedures. Methods We propose a step-function-based p-value model under the alternative hypothesis, which is simple enough to perform power analysis without simulations, but not too simple to lose the information from the alternative hypothesis. The first step is to transform distributions of different test statistics (e.g., t, chi-square or F to distributions of corresponding p-values. We then use a step function to approximate each of the p-value’s distributions by matching the mean and variance. Lastly, the step-function-based p-value model can be used for theoretical power analysis. Results The proposed model is applied to problems in multiple testing procedures. We first show how the most powerful critical constants can be chosen using the step-function-based p-value model. Our model is then applied to the field of multiple testing procedures to explain the assumption of monotonicity of the critical constants. Lastly, we apply our model to a behavioral weight loss and maintenance study to select the optimal critical constants. Conclusions The proposed model is easy to implement and preserves the information from the alternative hypothesis.

  5. Modified Truncated Multiplicity Analysis to Improve Verification of Uranium Fuel Cycle Materials

    International Nuclear Information System (INIS)

    LaFleur, A.; Miller, K.; Swinhoe, M.; Belian, A.; Croft, S.

    2015-01-01

    Accurate verification of 235U enrichment and mass in UF6 storage cylinders and the UO2F2 holdup contained in the process equipment is needed to improve international safeguards and nuclear material accountancy at uranium enrichment plants. Small UF6 cylinders (1.5'' and 5'' diameter) are used to store the full range of enrichments from depleted to highly-enriched UF6. For independent verification of these materials, it is essential that the 235U mass and enrichment measurements do not rely on facility operator declarations. Furthermore, in order to be deployed by IAEA inspectors to detect undeclared activities (e.g., during complementary access), it is also imperative that the measurement technique is quick, portable, and sensitive to a broad range of 235U masses. Truncated multiplicity analysis is a technique that reduces the variance in the measured count rates by only considering moments 1, 2, and 3 of the multiplicity distribution. This is especially important for reducing the uncertainty in the measured doubles and triples rates in environments with a high cosmic ray background relative to the uranium signal strength. However, we believe that the existing truncated multiplicity analysis throws away too much useful data by truncating the distribution after the third moment. This paper describes a modified truncated multiplicity analysis method that determines the optimal moment to truncate the multiplicity distribution based on the measured data. Experimental measurements of small UF6 cylinders and UO2F2 working reference materials were performed at Los Alamos National Laboratory (LANL). The data were analyzed using traditional and modified truncated multiplicity analysis to determine the optimal moment to truncate the multiplicity distribution to minimize the uncertainty in the measured count rates. The results from this analysis directly support nuclear safeguards at enrichment plants and provide a more accurate verification method for UF6

  6. Automatic differentiation for design sensitivity analysis of structural systems using multiple processors

    Science.gov (United States)

    Nguyen, Duc T.; Storaasli, Olaf O.; Qin, Jiangning; Qamar, Ramzi

    1994-01-01

    An automatic differentiation tool (ADIFOR) is incorporated into a finite element based structural analysis program for shape and non-shape design sensitivity analysis of structural systems. The entire analysis and sensitivity procedures are parallelized and vectorized for high performance computation. Small scale examples to verify the accuracy of the proposed program and a medium scale example to demonstrate the parallel vector performance on multiple CRAY C90 processors are included.

  7. Comparative Analysis of the Paravertebral Analgesic Pump Catheter with the Epidural Catheter in Elderly Trauma Patients with Multiple Rib Fractures.

    Science.gov (United States)

    Shapiro, Brian S; Wasfie, Tarik; Chadwick, Mathew; Barber, Kimberly R; Yapchai, Raquel

    2017-04-01

    Presently, trauma guidelines recommend epidural analgesia as the optimal modality of pain relief from rib fractures. They are not ideally suited for elderly trauma patients and have disadvantages including bleeding risk. The paravertebral analgesic pump (PVP) eliminates such disadvantages and includes ease of placement in the trauma setting. This study compares pain control in patients treated by EPI versus PVP. This is a retrospective, historical cohort study comparing two methods of pain management in the trauma setting. Before 2010, patients who had epidural catheters (EPI) placed for pain control were compared with patients after 2010 in which the PVP was used. All patients had multiple rib fractures as diagnosed by CT scan. Analysis was adjusted for age, number of fractures, and comorbid conditions. Multiple linear regression analysis was conducted to compare average reported pain. A total of 110 patients, 31 PVP and 79 epidural catheters, were included in the study. Overall mean age was 65 years. The mean Injury Severity Score was 12.0 (EPI) and 11.1 (PVP). Mean number rib fractures was 4.29 (EPI) and 4.71 (PVP). PVP was associated with a 30 per cent greater decrease in pain than that seen with EPI (6.0-1.9 vs 6.4-3.4). After controlling for age, Injury Severity Score, and number of rib fractures, there were no differences in intensive care unit or total length of stay (P = 0.35) or in pain score (3.76 vs 3.56, P = 0.64). In conclusion, the PVP compares well with epidural analgesia in older trauma patients yet is safe, well tolerated, and easily inserted.

  8. Analysis of Genome-Wide Association Studies with Multiple Outcomes Using Penalization

    Science.gov (United States)

    Liu, Jin; Huang, Jian; Ma, Shuangge

    2012-01-01

    Genome-wide association studies have been extensively conducted, searching for markers for biologically meaningful outcomes and phenotypes. Penalization methods have been adopted in the analysis of the joint effects of a large number of SNPs (single nucleotide polymorphisms) and marker identification. This study is partly motivated by the analysis of heterogeneous stock mice dataset, in which multiple correlated phenotypes and a large number of SNPs are available. Existing penalization methods designed to analyze a single response variable cannot accommodate the correlation among multiple response variables. With multiple response variables sharing the same set of markers, joint modeling is first employed to accommodate the correlation. The group Lasso approach is adopted to select markers associated with all the outcome variables. An efficient computational algorithm is developed. Simulation study and analysis of the heterogeneous stock mice dataset show that the proposed method can outperform existing penalization methods. PMID:23272092

  9. Frequency of exacerbations in patients with chronic obstructive pulmonary disease: an analysis of the SPIROMICS cohort.

    Science.gov (United States)

    Han, MeiLan K; Quibrera, Pedro M; Carretta, Elizabeth E; Barr, R Graham; Bleecker, Eugene R; Bowler, Russell P; Cooper, Christopher B; Comellas, Alejandro; Couper, David J; Curtis, Jeffrey L; Criner, Gerard; Dransfield, Mark T; Hansel, Nadia N; Hoffman, Eric A; Kanner, Richard E; Krishnan, Jerry A; Martinez, Carlos H; Pirozzi, Cheryl B; O'Neal, Wanda K; Rennard, Stephen; Tashkin, Donald P; Wedzicha, Jadwiga A; Woodruff, Prescott; Paine, Robert; Martinez, Fernando J

    2017-08-01

    Present treatment strategies to stratify exacerbation risk in patients with chronic obstructive pulmonary disease (COPD) rely on a history of two or more events in the previous year. We aimed to understand year to year variability in exacerbations and factors associated with consistent exacerbations over time. In this longitudinal, prospective analysis of exacerbations in the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) cohort, we analysed patients aged 40-80 years with COPD for whom 3 years of prospective data were available, identified through various means including care at academic and non-academic medical centres, word of mouth, and existing patient registries. Participants were enrolled in the study between Nov 12, 2010, and July 31, 2015. We classified patients according to yearly exacerbation frequency: no exacerbations in any year; one exacerbation in every year during 3 years of follow-up; and those with inconsistent exacerbations (individuals who had both years with exacerbations and years without during the 3 years of follow-up). Participants were characterised by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) spirometric category (1-4) on the basis of post-bronchodilator FEV 1 . Stepwise logistic regression was used to compare factors associated with one or more acute exacerbations of COPD every year for 3 years versus no exacerbations in the same timeframe. Additionally, a stepwise zero-inflated negative binomial model was used to assess predictors of exacerbation count during follow-up in all patients with available data. Baseline symptom burden was assessed with the COPD assessment test. This trial is registered with ClinicalTrials.gov, number NCT01969344. 2981 patients were enrolled during the study. 1843 patients had COPD, of which 1105 patients had 3 years of complete, prospective follow-up data. 538 (49%) of 1105 patients had at least one acute exacerbation during the 3 years of follow-up, whereas

  10. Shift work, night work, and the risk of prostate cancer: A meta-analysis based on 9 cohort studies.

    Science.gov (United States)

    Du, Hong-Bing; Bin, Kai-Yun; Liu, Wen-Hong; Yang, Feng-Sheng

    2017-11-01

    Epidemiology studies suggested that shift work or night work may be linked to prostate cancer (PCa); the relationship, however, remains controversy. PubMed, ScienceDirect, and Embase (Ovid) databases were searched before (started from the building of the databases) February 4, 2017 for eligible cohort studies. We pooled the evidence included by a random- or fixed-effect model, according to the heterogeneity. A predefined subgroup analysis was conducted to see the potential discrepancy between groups. Sensitivity analysis was used to test whether our results were stale. Nine cohort studies were eligible for meta-analysis with 2,570,790 male subjects. Our meta-analysis showed that, under the fixed-effect model, the pooled relevant risk (RR) of PCa was 1.05 (95% confidence interval [CI]: 1.00, 1.11; P = .06; I = 24.00%) for men who had ever engaged in night shift work; and under the random-effect model, the pooled RR was 1.08 (0.99, 1.17; P = .08; I = 24.00%). Subgroup analysis showed the RR of PCa among males in western countries was 1.05 (95% CI: 0.99, 1.11; P = .09; I = 0.00%), while among Asian countries it was 2.45 (95% CI: 1.19, 5.04; P = .02; I = 0.00%); and the RR was 1.04 (95% CI: 0.95, 1.14; P = .40; I = 29.20%) for the high-quality group compared with 1.21 (95% CI: 1.03, 1.41; P = .02; I = 0.00%) for the moderate/low-quality group. Sensitivity analysis showed robust results. Based on the current evidence of cohort studies, we found no obvious association between night shift work and PCa. However, our subgroup analysis suggests that night shift work may increase the risk of PCa in Asian men. Some evidence of a small study effect was observed in this meta-analysis.

  11. Young Adult and Usual Adult Body Mass Index and Multiple Myeloma Risk: A Pooled Analysis in the International Multiple Myeloma Consortium (IMMC).

    Science.gov (United States)

    Birmann, Brenda M; Andreotti, Gabriella; De Roos, Anneclaire J; Camp, Nicola J; Chiu, Brian C H; Spinelli, John J; Becker, Nikolaus; Benhaim-Luzon, Véronique; Bhatti, Parveen; Boffetta, Paolo; Brennan, Paul; Brown, Elizabeth E; Cocco, Pierluigi; Costas, Laura; Cozen, Wendy; de Sanjosé, Silvia; Foretová, Lenka; Giles, Graham G; Maynadié, Marc; Moysich, Kirsten; Nieters, Alexandra; Staines, Anthony; Tricot, Guido; Weisenburger, Dennis; Zhang, Yawei; Baris, Dalsu; Purdue, Mark P

    2017-06-01

    Background: Multiple myeloma risk increases with higher adult body mass index (BMI). Emerging evidence also supports an association of young adult BMI with multiple myeloma. We undertook a pooled analysis of eight case-control studies to further evaluate anthropometric multiple myeloma risk factors, including young adult BMI. Methods: We conducted multivariable logistic regression analysis of usual adult anthropometric measures of 2,318 multiple myeloma cases and 9,609 controls, and of young adult BMI (age 25 or 30 years) for 1,164 cases and 3,629 controls. Results: In the pooled sample, multiple myeloma risk was positively associated with usual adult BMI; risk increased 9% per 5-kg/m 2 increase in BMI [OR, 1.09; 95% confidence interval (CI), 1.04-1.14; P = 0.007]. We observed significant heterogeneity by study design ( P = 0.04), noting the BMI-multiple myeloma association only for population-based studies ( P trend = 0.0003). Young adult BMI was also positively associated with multiple myeloma (per 5-kg/m 2 ; OR, 1.2; 95% CI, 1.1-1.3; P = 0.0002). Furthermore, we observed strong evidence of interaction between younger and usual adult BMI ( P interaction adult BMI may increase multiple myeloma risk and suggest that healthy BMI maintenance throughout life may confer an added benefit of multiple myeloma prevention. Cancer Epidemiol Biomarkers Prev; 26(6); 876-85. ©2017 AACR . ©2017 American Association for Cancer Research.

  12. Obstetric and neonatal outcomes of pregnancies conceived after preimplantation genetic diagnosis: cohort study and meta-analysis.

    Science.gov (United States)

    Hasson, Joseph; Limoni, Dana; Malcov, Mira; Frumkin, Tsvia; Amir, Hadar; Shavit, Tal; Bay, BjØrn; Many, Ariel; Almog, Benjamin

    2017-08-01

    Preimplantation genetic diagnosis (PGD) may pose risks to pregnancy outcome owing to the invasiveness of the biopsy procedure. This study compares outcome of singleton and twin clinical pregnancies conceived after fresh embryo transfers of PGD (n = 89) and matched intracytoplasmic sperm injection (ICSI) pregnancies (n = 166). The study was carried out in a single university affiliated centre. Because of the paucity of available data, a literature-based meta-analysis of studies comparing neonatal outcome of PGD and ICSI pregnancies was also conducted. In the retrospective cohort study, obstetric and neonatal outcome were available in 67 PGD and 118 ICSI pregnancies. Perinatal outcomes were comparable between PGD and ICSI pregnancies. Meta-analysis revealed similar outcomes, except for higher rate of low birth weight (<2500 g) neonates in ICSI twin pregnancies (RR 0.86, 95% CI 0.74 to 1.0). Mean birth weight, gestational age at birth, pre-term deliveries (<37 weeks) and malformations were all comparable. In this cohort study and subsequent meta-analysis, no association was found between PGD conceived pregnancies and risks of adverse neonatal or obstetrical outcomes compared with ICSI pregnancies. Hence, blastomere biopsy for PGD does not seem to increase the risk for adverse perinatal outcome compared with ICSI pregnancies. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  13. Prediction of hearing outcomes by multiple regression analysis in patients with idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Suzuki, Hideaki; Tabata, Takahisa; Koizumi, Hiroki; Hohchi, Nobusuke; Takeuchi, Shoko; Kitamura, Takuro; Fujino, Yoshihisa; Ohbuchi, Toyoaki

    2014-12-01

    This study aimed to create a multiple regression model for predicting hearing outcomes of idiopathic sudden sensorineural hearing loss (ISSNHL). The participants were 205 consecutive patients (205 ears) with ISSNHL (hearing level ≥ 40 dB, interval between onset and treatment ≤ 30 days). They received systemic steroid administration combined with intratympanic steroid injection. Data were examined by simple and multiple regression analyses. Three hearing indices (percentage hearing improvement, hearing gain, and posttreatment hearing level [HLpost]) and 7 prognostic factors (age, days from onset to treatment, initial hearing level, initial hearing level at low frequencies, initial hearing level at high frequencies, presence of vertigo, and contralateral hearing level) were included in the multiple regression analysis as dependent and explanatory variables, respectively. In the simple regression analysis, the percentage hearing improvement, hearing gain, and HLpost showed significant correlation with 2, 5, and 6 of the 7 prognostic factors, respectively. The multiple correlation coefficients were 0.396, 0.503, and 0.714 for the percentage hearing improvement, hearing gain, and HLpost, respectively. Predicted values of HLpost calculated by the multiple regression equation were reliable with 70% probability with a 40-dB-width prediction interval. Prediction of HLpost by the multiple regression model may be useful to estimate the hearing prognosis of ISSNHL. © The Author(s) 2014.

  14. Lung cancer risk from radon - a joint analysis of three Czech miners cohorts

    International Nuclear Information System (INIS)

    Tomasek, L.; Placek, V.; Heribanova, A.

    1998-01-01

    The three cohorts were as follows: 4320 uranium miners first exposed in 1948-1959; 5624 miners who were working in uranium mines in 1968-1974, and 914 burnt-clay miners employed underground in 1960-1980. The statistical analyses were based on relative risk models in the general form O cE(1+ERR(W,Z)) where O is the observed number of cases, E is the number expected based on nationwide mortality data, and ERR is the excessive relative risk function depending on exposure (W) and modifying variables (Z). By the end of 1995, 888 cases of lung cancer were observed in the 3 cohorts, most of them in cohort 1, reflecting thus the high exposures and age. The simple model gives an ERR/WLM estimate (WLM = Working level Month; 1 WLM 3.54 = mJh/m 3 ) of 0.014 for the entire range of cumulative exposures (1-860 WLM), the intercept is 1.58. A somewhat steeper slope is seen at very low exposures. When the exposure range is restricted to less than 100 WLM, the ERR/WLM and intercept estimates are 0.023 and 1,25, respectively. Even at 10-20 WLM, the relative risk is significantly different from the baseline rate. The main reasons for the differences between the two global estimates of ERR/WLM are (i) the exposure rate effect, (ii) the different periods of follow-up after exposure, and (iii) the age structure of miners at work. The effect of smoking was also taken into account. (P.A.)

  15. Analysis of healthy cohorts for single nucleotide polymorphisms in C1q gene cluster

    Directory of Open Access Journals (Sweden)

    MARIA A. RADANOVA

    2015-12-01

    Full Text Available C1q is the first component of the classical pathway of complement activation. The coding region for C1q is localized on chromosome 1p34.1–36.3. Mutations or single nucleotide polymorphisms (SNPs in C1q gene cluster can cause developing of Systemic lupus erythematosus (SLE because of C1q deficiency or other unknown reason. We selected five SNPs located in 7.121 kbp region on chromosome 1, which were previously associated with SLE and/or low C1q level, but not causing C1q deficiency and analyzed them in terms of allele frequencies and genotype distribution in comparison with Hispanic, Asian, African and other Caucasian cohorts. These SNPs were: rs587585, rs292001, rs172378, rs294179 and rs631090. One hundred eighty five healthy Bulgarian volunteers were genotyped for the selected five C1q SNPs by quantative real-time PCR methods. International HapMap Project has been used for information about genotype distribution and allele frequencies of the five SNPs in, Hispanics, Asians, Africans and others Caucasian cohorts. Bulgarian healthy volunteers and another pooled Caucasian cohort had similar frequencies of genotypes and alleles of rs587585, rs292001, rs294179 and rs631090 SNPs. Nevertheless, genotype AA of rs172378 was significantly overrepresented in Bulgarians when compared to other healthy Caucasians from USA and UK (60% vs 31%. Genotype distribution of rs172378 in Bulgarians was similar to Greek-Cyriot Caucasians. For all Caucasians the major allele of rs172378 was A. This is the first study analyzing the allele frequencies and genotype distribution of C1q gene cluster SNPs in Bulgarian healthy population.

  16. Gene-by-Psychosocial Factor Interactions Influence Diastolic Blood Pressure in European and African Ancestry Populations: Meta-Analysis of Four Cohort Studies

    Directory of Open Access Journals (Sweden)

    Jennifer A. Smith

    2017-12-01

    Full Text Available Inter-individual variability in blood pressure (BP is influenced by both genetic and non-genetic factors including socioeconomic and psychosocial stressors. A deeper understanding of the gene-by-socioeconomic/psychosocial factor interactions on BP may help to identify individuals that are genetically susceptible to high BP in specific social contexts. In this study, we used a genomic region-based method for longitudinal analysis, Longitudinal Gene-Environment-Wide Interaction Studies (LGEWIS, to evaluate the effects of interactions between known socioeconomic/psychosocial and genetic risk factors on systolic and diastolic BP in four large epidemiologic cohorts of European and/or African ancestry. After correction for multiple testing, two interactions were significantly associated with diastolic BP. In European ancestry participants, outward/trait anger score had a significant interaction with the C10orf107 genomic region (p = 0.0019. In African ancestry participants, depressive symptom score had a significant interaction with the HFE genomic region (p = 0.0048. This study provides a foundation for using genomic region-based longitudinal analysis to identify subgroups of the population that may be at greater risk of elevated BP due to the combined influence of genetic and socioeconomic/psychosocial risk factors.

  17. Education in Twins and Their Parents Across Birth Cohorts Over 100 years: An Individual-Level Pooled Analysis of 42-Twin Cohorts.

    Science.gov (United States)

    Silventoinen, Karri; Jelenkovic, Aline; Latvala, Antti; Sund, Reijo; Yokoyama, Yoshie; Ullemar, Vilhelmina; Almqvist, Catarina; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth J F; Kandler, Christian; Honda, Chika; Inui, Fujio; Iwatani, Yoshinori; Watanabe, Mikio; Rebato, Esther; Stazi, Maria A; Fagnani, Corrado; Brescianini, Sonia; Hur, Yoon-Mi; Jeong, Hoe-Uk; Cutler, Tessa L; Hopper, John L; Busjahn, Andreas; Saudino, Kimberly J; Ji, Fuling; Ning, Feng; Pang, Zengchang; Rose, Richard J; Koskenvuo, Markku; Heikkilä, Kauko; Cozen, Wendy; Hwang, Amie E; Mack, Thomas M; Siribaddana, Sisira H; Hotopf, Matthew; Sumathipala, Athula; Rijsdijk, Fruhling; Sung, Joohon; Kim, Jina; Lee, Jooyeon; Lee, Sooji; Nelson, Tracy L; Whitfield, Keith E; Tan, Qihua; Zhang, Dongfeng; Llewellyn, Clare H; Fisher, Abigail; Burt, S Alexandra; Klump, Kelly L; Knafo-Noam, Ariel; Mankuta, David; Abramson, Lior; Medland, Sarah E; Martin, Nicholas G; Montgomery, Grant W; Magnusson, Patrik K E; Pedersen, Nancy L; Dahl Aslan, Anna K; Corley, Robin P; Huibregtse, Brooke M; Öncel, Sevgi Y; Aliev, Fazil; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Willemsen, Gonneke; Bartels, Meike; van Beijsterveldt, Catharina E M; Silberg, Judy L; Eaves, Lindon J; Maes, Hermine H; Harris, Jennifer R; Brandt, Ingunn; Nilsen, Thomas S; Rasmussen, Finn; Tynelius, Per; Baker, Laura A; Tuvblad, Catherine; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Gatz, Margaret; Butler, David A; Lichtenstein, Paul; Goldberg, Jack H; Harden, K Paige; Tucker-Drob, Elliot M; Duncan, Glen E; Buchwald, Dedra; Tarnoki, Adam D; Tarnoki, David L; Franz, Carol E; Kremen, William S; Lyons, Michael J; Maia, José A; Freitas, Duarte L; Turkheimer, Eric; Sørensen, Thorkild I A; Boomsma, Dorret I; Kaprio, Jaakko

    2017-10-01

    Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990-1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.

  18. What is the benefit of treatment with multiple lines of chemotherapy for patients with metastatic breast cancer? A retrospective cohort study.

    Science.gov (United States)

    Bakker, J L; Wever, K; van Waesberghe, J H; Beeker, A; Meijers-Heijboer, H; Konings, I R; Verheul, H M W

    2015-12-01

    Despite the extensive clinical experience, it is still under debate to what extent patients with metastatic breast cancer (MBC) benefit from multiple lines of chemotherapy beyond standard first or second line treatment. Selection of patients with MBC who will benefit from treatment is crucial to improve outcome and reduce unnecessary toxicity. In this retrospective study, systemic treatment outcome for patients with metastatic MBC is being evaluated. We evaluated to what extent the clinical benefit of prior chemotherapy can predict the success of a subsequent treatment line. Ninety-one patients treated with chemotherapy for MBC between January 2005 and January 2009 were included in this study. Clinical characteristics of patients, choices of chemotherapy and response at first evaluation of every treatment line was evaluated based on radiologic and clinical data. Patients received multiple systemic cytotoxic and biological (combination) therapies. 30% of these patients received more than five consecutive systemic (combination) treatments. First line chemotherapy was mostly anthracycline-based, followed by taxanes, capecitabine and vinorelbine. The response rate (RR, complete response plus partial response according to RECIST 1.1) decreased from 20% (95% CI 11-28%) upon first line of treatment to 0% upon the fourth line. The clinical benefit rate (combining RR and stable disease) decreased from 85% (95% CI 78-93%) in the first to 54% (95% CI 26-67) upon the fourth line. 24% of the patients with clinical benefit at first evaluation did not receive a subsequent line of treatment when progressive disease occurred, while sixty-one percent of the patients with progressive disease at first evaluation of a treatment did not receive a subsequent line of chemotherapy. When applied, the efficacy of a subsequent line of treatment was similar for patients independent of previous treatment benefit. The clinical benefit at first evaluation from systemic treatment in MBC does not

  19. Managing cancer pain at the end of life with multiple strong opioids: a population-based retrospective cohort study in primary care.

    Directory of Open Access Journals (Sweden)

    Wei Gao

    Full Text Available End-of-life cancer patients commonly receive more than one type of strong opioid. The three-step analgesic ladder framework of the World Health Organisation (WHO provides no guidance on multiple opioid prescribing and there is little epidemiological data available to inform practice. This study aims to investigate the time trend of such cases and the associated factors.Strong opioid prescribing in the last three months of life of cancer patients were extracted from the General Practice Research Database (GPRD. The outcome variable was the number of different types of prescribed non-rescue doses of opioids (1 vs 2-4, referred to as a complex case. Associated factors were evaluated using prevalence ratios (PR derived from multivariate log-binomial model, adjusting for clustering effects and potential confounding variables.Overall, 26.4% (95% CI: 25.6-27.1% of 13,427 cancer patients (lung 41.7%, colorectal 19.1%, breast 18.6%, prostate 15.5%, head and neck 5.0% were complex cases. Complex cases increased steadily over the study period (1.02% annually, 95%CI: 0.42-1.61%, p = 0.048 but with a small dip (7.5% reduction, 95%CI: -0.03 to 17.8% around the period of the Shipman case, a British primary care doctor who murdered his patients with opioids. The dip significantly affected the correlation of the complex cases with persistent increasing background opioid prescribing (weighted correlation coefficients pre-, post-Shipman periods: 0.98(95%CI: 0.67-1.00, p = 0.011; 0.14 (95%CI: -0.85 to 0.91, p = 0.85. Multivariate adjusted analysis showed that the complex cases were predominantly associated with year of death (PRs vs 2000: 1.05-1.65, not other demographic and clinical factors except colorectal cancer (PR vs lung cancer: 1.24, 95%CI: 1.12-1.37.These findings suggest that prescribing behaviour, rather than patient factors, plays an important role in multiple opioid prescribing at the end of life; highlighting the need for training and

  20. Obstetric outcomes in women with polycystic ovary syndrome and isolated polycystic ovaries undergoing in vitro fertilization: a retrospective cohort analysis.

    Science.gov (United States)

    Wan, Hei Lok Tiffany; Hui, Pui Wah; Li, Hang Wun Raymond; Ng, Ernest Hung Yu

    2015-03-01

    This retrospective cohort study evaluated the obstetric outcomes in women with polycystic ovary syndrome (PCOS) and isolated polycystic ovaries (PCO) undergoing in vitro fertilization (IVF) treatment. We studied 104 women with PCOS, 184 with PCO and 576 age-matched controls undergoing the first IVF treatment cycle between 2002 and 2009. Obstetric outcomes and complications including gestational diabetes (GDM), gestational hypertension (GHT), gestational proteinuric hypertension (PET), intrauterine growth restriction (IUGR), gestation at delivery, baby's Apgar scores and admission to the neonatal intensive care unit (NICU) were reviewed. Among the 864 patients undergoing IVF treatment, there were 253 live births in total (25 live births in the PCOS group, 54 in the PCO group and 174 in the control group). The prevalence of obstetric complications (GDM, GHT, PET and IUGR) and the obstetric outcomes (gestation at delivery, birth weight, Apgar scores and NICU admissions) were comparable among the three groups. Adjustments for age and multiple pregnancies were made using multiple logistic regression and we found no statistically significant difference among the three groups. Patients with PCO ± PCOS do not have more adverse obstetric outcomes when compared with non-PCO patients undergoing IVF treatment.

  1. Non-destructive assay of fissile materials by detection and multiplicity analysis of spontaneous neutrons

    International Nuclear Information System (INIS)

    Prosdocimi, A.

    1979-01-01

    A method for determining the absolute reaction rate of nuclear events giving rise to neutron emission, according to their neutron multiplicity, is proposed. A typical application is the measurement of the (α, n) and spontaneous fission rates in a fissile material sample, particularly of Pu oxide composition. An analysis of random and correlated neutron pulses is carried out on the basis of sequential order without requiring any time interval analysis, then the primary nuclear events are sorted versus their neutron multiplicity. Suitable theoretical relationships enable to derive the absolute (α, n) and SF reaction rates when the physical parameters of the neutron detector and the multiplicity spectrumm of pulses are known. A typical device is described and the results of experiments leading to Pu-239 and Pu-240 assay are given

  2. Estimate the contribution of incubation parameters influence egg hatchability using multiple linear regression analysis.

    Science.gov (United States)

    Khalil, Mohamed H; Shebl, Mostafa K; Kosba, Mohamed A; El-Sabrout, Karim; Zaki, Nesma

    2016-08-01

    This research was conducted to determine the most affecting parameters on hatchability of indigenous and improved local chickens' eggs. Five parameters were studied (fertility, early and late embryonic mortalities, shape index, egg weight, and egg weight loss) on four strains, namely Fayoumi, Alexandria, Matrouh, and Montazah. Multiple linear regression was performed on the studied parameters to determine the most influencing one on hatchability. The results showed significant differences in commercial and scientific hatchability among strains. Alexandria strain has the highest significant commercial hatchability (80.70%). Regarding the studied strains, highly significant differences in hatching chick weight among strains were observed. Using multiple linear regression analysis, fertility made the greatest percent contribution (71.31%) to hatchability, and the lowest percent contributions were made by shape index and egg weight loss. A prediction of hatchability using multiple regression analysis could be a good tool to improve hatchability percentage in chickens.

  3. Theoretical analysis of moiré fringe multiplication under a scanning electron microscope

    International Nuclear Information System (INIS)

    Li, Yanjie; Xie, Huimin; Chen, Pengwan; Zhang, Qingming

    2011-01-01

    In this study, theoretical analysis and experimental verification of fringe multiplication under a scanning electron microscope (SEM) are presented. Fringe multiplication can be realized by enhancing the magnification or the number of scanning lines under the SEM. A universal expression of the pitch of moiré fringes is deduced. To apply this method to deformation measurement, the calculation formulas of strain and displacement are derived. Compared to natural moiré, the displacement sensitivity is increased by fringe multiplication while the strain sensitivity may be retained or enhanced depending on the number of scanning lines used. The moiré patterns are formed by the interference of a 2000 lines mm −1 grating with the scanning lines of SEM, and the measured parameters of moiré fringes from experimental results agree well with theoretical analysis

  4. Association of Multiple Melanocytic Naevi with Education, Sex and Skin Type. A Northern Finland Birth Cohort 1966 Study with 46 Years Follow-up.

    Science.gov (United States)

    Sinikumpu, Suvi-Päivikki; Huilaja, Laura; Jokelainen, Jari; Auvinen, Juha; Timonen, Markku; Tasanen, Kaisa

    2017-02-08

    Having multiple melanocytic naevi (sex, socioeconomic status (education) in childhood and adulthood, skin type and sunbathing habits. The prevalence of multiple melanocytic naevi was 11.6% (223/1,930). Higher education (odds ratio (OR) 2.11, 95% confidence interval (95% CI) 1.51-2.96), male sex (OR 1.48, 95% CI 1.07-2.06), sun-sensitive skin type (OR 2.09, 95% CI 1.34-3.27) and regular use of sunscreen (OR 2.03, 95% CI 1.23-3.37) were associated with increased risk of multiple naevi. Inflammatory skin diseases decreased (OR 0.49, 95 CI% 0.33-0.72) the risk of multiple naevi. In conclusion, several risk factors were found for multiple naevi among adults living in high latitudes, in Northern Finland.

  5. [A factor analysis method for contingency table data with unlimited multiple choice questions].

    Science.gov (United States)

    Toyoda, Hideki; Haiden, Reina; Kubo, Saori; Ikehara, Kazuya; Isobe, Yurie

    2016-02-01

    The purpose of this study is to propose a method of factor analysis for analyzing contingency tables developed from the data of unlimited multiple-choice questions. This method assumes that the element of each cell of the contingency table has a binominal distribution and a factor analysis model is applied to the logit of the selection probability. Scree plot and WAIC are used to decide the number of factors, and the standardized residual, the standardized difference between the sample, and the proportion ratio, is used to select items. The proposed method was applied to real product impression research data on advertised chips and energy drinks. Since the results of the analysis showed that this method could be used in conjunction with conventional factor analysis model, and extracted factors were fully interpretable, and suggests the usefulness of the proposed method in the study of psychology using unlimited multiple-choice questions.

  6. Multiple brain networks underpinning word learning from fluent speech revealed by independent component analysis.

    Science.gov (United States)

    López-Barroso, Diana; Ripollés, Pablo; Marco-Pallarés, Josep; Mohammadi, Bahram; Münte, Thomas F; Bachoud-Lévi, Anne-Catherine; Rodriguez-Fornells, Antoni; de Diego-Balaguer, Ruth

    2015-04-15

    Although neuroimaging studies using standard subtraction-based analysis from functional magnetic resonance imaging (fMRI) have suggested that frontal and temporal regions are involved in word learning from fluent speech, the possible contribution of different brain networks during this type of learning is still largely unknown. Indeed, univariate fMRI analyses cannot identify the full extent of distributed networks that are engaged by a complex task such as word learning. Here we used Independent Component Analysis (ICA) to characterize the different brain networks subserving word learning from an artificial language speech stream. Results were replicated in a second cohort of participants with a different linguistic background. Four spatially independent networks were associated with the task in both cohorts: (i) a dorsal Auditory-Premotor network; (ii) a dorsal Sensory-Motor network; (iii) a dorsal Fronto-Parietal network; and (iv) a ventral Fronto-Temporal network. The level of engagement of these networks varied through the learning period with only the dorsal Auditory-Premotor network being engaged across all blocks. In addition, the connectivity strength of this network in the second block of the learning phase correlated with the individual variability in word learning performance. These findings suggest that: (i) word learning relies on segregated connectivity patterns involving dorsal and ventral networks; and (ii) specifically, the dorsal auditory-premotor network connectivity strength is directly correlated with word learning performance. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Consumption of Yogurt and the Incident Risk of Cardiovascular Disease: A Meta-Analysis of Nine Cohort Studies.

    Science.gov (United States)

    Wu, Lei; Sun, Dali

    2017-03-22

    Previous systematic reviews and meta-analyses have evaluated the association of dairy consumption and the risk of cardiovascular disease (CVD). However, the findings were inconsistent. No quantitative analysis has specifically assessed the effect of yogurt intake on the incident risk of CVD. We searched the PubMed and the Embase databases from inception to 10 January 2017. A generic inverse-variance method was used to pool the fully-adjusted relative risks (RRs) and the corresponding 95% confidence intervals (CIs) with a random-effects model. A generalized least squares trend estimation model was used to calculate the specific slopes in the dose-response analysis. The present systematic review and meta-analysis identified nine prospective cohort articles involving a total of 291,236 participants. Compared with the lowest category, highest category of yogurt consumption was not significantly related with the incident risk of CVD, and the RR (95% CI) was 1.01 (0.95, 1.08) with an evidence of significant heterogeneity (I² = 52%). However, intake of ≥200 g/day yogurt was significantly associated with a lower risk of CVD in the subgroup analysis. There was a trend that a higher level of yogurt consumption was associated with a lower incident risk of CVD in the dose-response analysis. A daily dose of ≥200 g yogurt intake might be associated with a lower incident risk of CVD. Further cohort studies and randomized controlled trials are still demanded to establish and confirm the observed association in populations with different characteristics.

  8. Predictors of postoperative outcomes of cubital tunnel syndrome treatments using multiple logistic regression analysis.

    Science.gov (United States)

    Suzuki, Taku; Iwamoto, Takuji; Shizu, Kanae; Suzuki, Katsuji; Yamada, Harumoto; Sato, Kazuki

    2017-05-01

    This retrospective study was designed to investigate prognostic factors for postoperative outcomes for cubital tunnel syndrome (CubTS) using multiple logistic regression analysis with a large number of patients. Eighty-three patients with CubTS who underwent surgeries were enrolled. The following potential prognostic factors for disease severity were selected according to previous reports: sex, age, type of surgery, disease duration, body mass index, cervical lesion, presence of diabetes mellitus, Workers' Compensation status, preoperative severity, and preoperative electrodiagnostic testing. Postoperative severity of disease was assessed 2 years after surgery by Messina's criteria which is an outcome measure specifically for CubTS. Bivariate analysis was performed to select candidate prognostic factors for multiple linear regression analyses. Multiple logistic regression analysis was conducted to identify the association between postoperative severity and selected prognostic factors. Both bivariate and multiple linear regression analysis revealed only preoperative severity as an independent risk factor for poor prognosis, while other factors did not show any significant association. Although conflicting results exist regarding prognosis of CubTS, this study supports evidence from previous studies and concludes early surgical intervention portends the most favorable prognosis. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  9. Analysis of Product Sampling for New Product Diffusion Incorporating Multiple-Unit Ownership

    Directory of Open Access Journals (Sweden)

    Zhineng Hu

    2014-01-01

    Full Text Available Multiple-unit ownership of nondurable products is an important component of sales in many product categories. Based on the Bass model, this paper develops a new model considering the multiple-unit adoptions as a diffusion process under the influence of product sampling. Though the analysis aims to determine the optimal dynamic sampling effort for a firm and the results demonstrate that experience sampling can accelerate the diffusion process, the best time to send free samples is just before the product being launched. Multiple-unit purchasing behavior can increase sales to make more profit for a firm, and it needs more samples to make the product known much better. The local sensitivity analysis shows that the increase of both external coefficients and internal coefficients has a negative influence on the sampling level, but the internal influence on the subsequent multiple-unit adoptions has little significant influence on the sampling. Using the logistic regression along with linear regression, the global sensitivity analysis gives a whole analysis of the interaction of all factors, which manifests the external influence and multiunit purchase rate are two most important factors to influence the sampling level and net present value of the new product, and presents a two-stage method to determine the sampling level.

  10. Sensitivity Analysis of Multiple Informant Models When Data Are Not Missing at Random

    Science.gov (United States)

    Blozis, Shelley A.; Ge, Xiaojia; Xu, Shu; Natsuaki, Misaki N.; Shaw, Daniel S.; Neiderhiser, Jenae M.; Scaramella, Laura V.; Leve, Leslie D.; Reiss, David

    2013-01-01

    Missing data are common in studies that rely on multiple informant data to evaluate relationships among variables for distinguishable individuals clustered within groups. Estimation of structural equation models using raw data allows for incomplete data, and so all groups can be retained for analysis even if only 1 member of a group contributes…

  11. Computational Tools for Probing Interactions in Multiple Linear Regression, Multilevel Modeling, and Latent Curve Analysis

    Science.gov (United States)

    Preacher, Kristopher J.; Curran, Patrick J.; Bauer, Daniel J.

    2006-01-01

    Simple slopes, regions of significance, and confidence bands are commonly used to evaluate interactions in multiple linear regression (MLR) models, and the use of these techniques has recently been extended to multilevel or hierarchical linear modeling (HLM) and latent curve analysis (LCA). However, conducting these tests and plotting the…

  12. Meaning Making through Multiple Modalities in a Biology Classroom: A Multimodal Semiotics Discourse Analysis

    Science.gov (United States)

    Jaipal, Kamini

    2010-01-01

    The teaching of science is a complex process, involving the use of multiple modalities. This paper illustrates the potential of a multimodal semiotics discourse analysis framework to illuminate meaning-making possibilities during the teaching of a science concept. A multimodal semiotics analytical framework is developed and used to (1) analyze the…

  13. Application of range-test in multiple linear regression analysis in ...

    African Journals Online (AJOL)

    Application of range-test in multiple linear regression analysis in the presence of outliers is studied in this paper. First, the plot of the explanatory variables (i.e. Administration, Social/Commercial, Economic services and Transfer) on the dependent variable (i.e. GDP) was done to identify the statistical trend over the years.

  14. Analysis of the quantitative dermatoglyphics of the digito-palmar complex in patients with multiple sclerosis.

    Science.gov (United States)

    Supe, S; Milicić, J; Pavićević, R

    1997-06-01

    Recent studies on the etiopathogenesis of multiple sclerosis (MS) all point out that there is a polygenetical predisposition for this illness. The so called "MS Trait" determines the reactivity of the immunological system upon ecological factors. The development of the glyphological science and the study of the characteristics of the digito-palmar dermatoglyphic complex (for which it was established that they are polygenetically determined characteristics) all enable a better insight into the genetic development during early embriogenesis. The aim of this study was to estimate certain differences in the dermatoglyphics of digito-palmar complexes between the group with multiple sclerosis and the comparable, phenotypically healthy groups of both sexes. This study is based on the analysis of 18 quantitative characteristics of the digito-palmar complex in 125 patients with multiple sclerosis (41 males and 84 females) in comparison to a group of 400 phenotypically healthy patients (200 males and 200 females). The conducted analysis pointed towards a statistically significant decrease of the number of digital and palmar ridges, as well as with lower values of atd angles in a group of MS patients of both sexes. The main discriminators were the characteristic palmar dermatoglyphics with the possibility that the discriminate analysis classifies over 80% of the examinees which exceeds the statistical significance. The results of this study suggest a possible discrimination of patients with MS and the phenotypically health population through the analysis of the dermatoglyphic status, and therefore the possibility that multiple sclerosis is genetically predisposed disease.

  15. Analysis of multiple single nucleotide polymorphisms (SNP) on DNA traces from plasma and dried blood samples

    NARCIS (Netherlands)

    Catsburg, Arnold; van der Zwet, Wil C.; Morre, Servaas A.; Ouburg, Sander; Vandenbroucke-Grauls, Christina M. J. E.; Savelkoul, Paul H. M.

    2007-01-01

    Reliable analysis of single nucleotide polymorphisms (SNPs) in DNA derived from samples containing low numbers of cells or from suboptimal sources can be difficult. A new procedure to characterize multiple SNPs in traces of DNA from plasma and old dried blood samples was developed. Six SNPs in the

  16. Stepwise Analysis of Differential Item Functioning Based on Multiple-Group Partial Credit Model.

    Science.gov (United States)

    Muraki, Eiji

    1999-01-01

    Extended an Item Response Theory (IRT) method for detection of differential item functioning to the partial credit model and applied the method to simulated data using a stepwise procedure. Then applied the stepwise DIF analysis based on the multiple-group partial credit model to writing trend data from the National Assessment of Educational…

  17. IsoGeneGUI : Multiple approaches for dose-response analysis of microarray data using R

    NARCIS (Netherlands)

    Otava, Martin; Sengupta, Rudradev; Shkedy, Ziv; Lin, Dan; Pramana, Setia; Verbeke, Tobias; Haldermans, Philippe; Hothorn, Ludwig A.; Gerhard, Daniel; Kuiper, Rebecca M.; Klinglmueller, Florian; Kasim, Adetayo

    2017-01-01

    The analysis of transcriptomic experiments with ordered covariates, such as dose-response data, has become a central topic in bioinformatics, in particular in omics studies. Consequently, multiple R packages on CRAN and Bioconductor are designed to analyse microarray data from various perspectives

  18. The Multiplicative Zak Transform, Dimension Reduction, and Wavelet Analysis of LIDAR Data

    Science.gov (United States)

    2010-01-01

    systems is likely to fail. Auslander, Eichmann , Gertner, and Tolimieri defined a multiplicative Zak transform [1], mimicking the construction of the Gabor...L. Auslander, G. Eichmann , I. Gertner and R. Tolimieri, “Time-Frequency Analysis and Synthesis of Non-Stationary Signals,” Proc. Soc. Photo-Opt. In

  19. It's Deja Vu All over Again: Using Multiple-Spell Discrete-Time Survival Analysis.

    Science.gov (United States)

    Willett, John B.; Singer, Judith D.

    1995-01-01

    The multiple-spell discrete-time survival analysis method is introduced and illustrated using longitudinal data on exit from and reentry into the teaching profession. The method is applicable to many educational problems involving the sequential occurrence of disparate events or episodes. (SLD)

  20. Analysis of Multiple Genomic Sequence Alignments: A Web Resource, Online Tools, and Lessons Learned From Analysis of Mammalian SCL Loci

    Science.gov (United States)

    Chapman, Michael A.; Donaldson, Ian J.; Gilbert, James; Grafham, Darren; Rogers, Jane; Green, Anthony R.; Göttgens, Berthold

    2004-01-01

    Comparative analysis of genomic sequences is becoming a standard technique for studying gene regulation. However, only a limited number of tools are currently available for the analysis of multiple genomic sequences. An extensive data set for the testing and training of such tools is provided by the SCL gene locus. Here we have expanded the data set to eight vertebrate species by sequencing the dog SCL locus and by annotating the dog and rat SCL loci. To provide a resource for the bioinformatics community, all SCL sequences and functional annotations, comprising a collation of the extensive experimental evidence pertaining to SCL regulation, have been made available via a Web server. A Web interface to new tools specifically designed for the display and analysis of multiple sequence alignments was also implemented. The unique SCL data set and new sequence comparison tools allowed us to perform a rigorous examination of the true benefits of multiple sequence comparisons. We demonstrate that multiple sequence alignments are, overall, superior to pairwise alignments for identification of mammalian regulatory regions. In the search for individual transcription factor binding sites, multiple alignments markedly increase the signal-to-noise ratio compared to pairwise alignments. PMID:14718377

  1. High throughput LC-MS/MS method for the simultaneous analysis of multiple vitamin D analytes in serum.

    Science.gov (United States)

    Jenkinson, Carl; Taylor, Angela E; Hassan-Smith, Zaki K; Adams, John S; Stewart, Paul M; Hewison, Martin; Keevil, Brian G

    2016-03-01

    Recent studies suggest that vitamin D-deficiency is linked to increased risk of common human health problems. To define vitamin D 'status' most routine analytical methods quantify one particular vitamin D metabolite, 25-hydroxyvitamin D3 (25OHD3). However, vitamin D is characterized by complex metabolic pathways, and simultaneous measurement of multiple vitamin D metabolites may provide a more accurate interpretation of vitamin D status. To address this we developed a high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to analyse multiple vitamin D analytes, with particular emphasis on the separation of epimer metabolites. A supportive liquid-liquid extraction (SLE) and LC-MS/MS method was developed to quantify 10 vitamin D metabolites as well as separation of an interfering 7α-hydroxy-4-cholesten-3-one (7αC4) isobar (precursor of bile acid), and validated by analysis of human serum samples. In a cohort of 116 healthy subjects, circulating concentrations of 25-hydroxyvitamin D3 (25OHD3), 3-epi-25-hydroxyvitamin D3 (3-epi-25OHD3), 24,25-dihydroxyvitamin D3 (24R,25(OH)2D3), 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3), and 25-hydroxyvitamin D2 (25OHD2) were quantifiable using 220μL of serum, with 25OHD3 and 24R,25(OH)2D3 showing significant seasonal variations. This high-throughput LC-MS/MS method provides a novel strategy for assessing the impact of vitamin D on human health and disease. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Genome-wide association meta-analysis of fish and EPA+DHA consumption in 17 US and European cohorts.

    Directory of Open Access Journals (Sweden)

    Dariush Mozaffarian

    Full Text Available Regular fish and omega-3 consumption may have several health benefits and are recommended by major dietary guidelines. Yet, their intakes remain remarkably variable both within and across populations, which could partly owe to genetic influences.To identify common genetic variants that influence fish and dietary eicosapentaenoic acid plus docosahexaenoic acid (EPA+DHA consumption.We conducted genome-wide association (GWA meta-analysis of fish (n = 86,467 and EPA+DHA (n = 62,265 consumption in 17 cohorts of European descent from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium Nutrition Working Group. Results from cohort-specific GWA analyses (additive model for fish and EPA+DHA consumption were adjusted for age, sex, energy intake, and population stratification, and meta-analyzed separately using fixed-effect meta-analysis with inverse variance weights (METAL software. Additionally, heritability was estimated in 2 cohorts.Heritability estimates for fish and EPA+DHA consumption ranged from 0.13-0.24 and 0.12-0.22, respectively. A significant GWA for fish intake was observed for rs9502823 on chromosome 6: each copy of the minor allele (FreqA = 0.015 was associated with 0.029 servings/day (~1 serving/month lower fish consumption (P = 1.96x10-8. No significant association was observed for EPA+DHA, although rs7206790 in the obesity-associated FTO gene was among top hits (P = 8.18x10-7. Post-hoc calculations demonstrated 95% statistical power to detect a genetic variant associated with effect size of 0.05% for fish and 0.08% for EPA+DHA.These novel findings suggest that non-genetic personal and environmental factors are principal determinants of the remarkable variation in fish consumption, representing modifiable targets for increasing intakes among all individuals. Genes underlying the signal at rs72838923 and mechanisms for the association warrant further investigation.

  3. Choosing of mode and calculation of multiple regression equation parameters in X-ray radiometric analysis

    International Nuclear Information System (INIS)

    Mamikonyan, S.V.; Berezkin, V.V.; Lyubimova, S.V.; Svetajlo, Yu.N.; Shchekin, K.I.

    1978-01-01

    A method to derive multiple regression equations for X-ray radiometric analysis is described. Te method is realized in the form of the REGRA program in an algorithmic language. The subprograms included in the program are describe. In analyzing cement for Mg, Al, Si, Ca and Fe contents as an example, the obtainment of working equations in the course of calculations by the program is shown to simpliy the realization of computing devices in instruments for X-ray radiometric analysis

  4. Cannabis and intractable chronic pain: an explorative retrospective analysis of Italian cohort of 614 patients

    Directory of Open Access Journals (Sweden)

    Fanelli G

    2017-05-01

    Full Text Available Guido Fanelli,1,2 Giuliano De Carolis,3 Claudio Leonardi,4 Adele Longobardi,5,6 Ennio Sarli,7,8 Massimo Allegri,1,2 Michael E Schatman9 1Anesthesia, Critical Care and Pain Medicine Unit, Division of Surgical Sciences, Department of Medicine and Surgery, University of Parma, 2Anesthesia, Intensive Care and Pain Therapy Service, Azienda Ospedaliero Universitaria Parma, Parma, 3Pain Therapy Service, Azienda Ospedaliero Universitaria Pisana, Pisa, 4Department of Drug Addiction Diseases, Local Public Health of Rome, Rome, 5Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples “Federico II”, Naples, 6Young Against the Pain (YAP Group, Parma, 7Progetti Live Surgery, 8PinHub Group, Florence, Italy; 9Department of Public Health and Community Medicine, Tufts University School of Medicine, Boston, MA, USA Background: Despite growing interest in the therapeutic use of cannabis to manage chronic pain, only limited data that address these issues are available. In recent years, a number of nations have introduced specific laws to allow patients to use cannabis preparations to treat a variety of medical conditions. In 2015, the Italian government authorized the use of cannabis to treat several diseases, including chronic pain generally, spasticity in multiple sclerosis, cachexia and anorexia among AIDS and cancer patients, glaucoma, Tourette syndrome, and certain types of epilepsy. We present the first snapshot of the Italian experience with cannabis use for chronic pain over the initial year of its use.Methods: This is a retrospective case series analysis of all chronic pain patients treated with oral or vaporized cannabis in six hubs during the initial year following the approval of the new Italian law (December 2015 to November 2016. We evaluated routes of administration, types of cannabis products utilized, dosing, and effectiveness and safety of the treatment.Results: As only one of the six centers has

  5. Population-based analysis of patients with COPD in Catalonia: a cohort study with implications for clinical management

    Science.gov (United States)

    Vela, Emili; Tényi, Ákos; Cano, Isaac; Monterde, David; Cleries, Montserrat; Garcia-Altes, Anna; Hernandez, Carme; Escarrabill, Joan; Roca, Josep

    2018-01-01

    Background Clinical management of patients with chronic obstructive pulmonary disease (COPD) shows potential for improvement provided that patients’ heterogeneities are better understood. The study addresses the impact of comorbidities and its role in health risk assessment. Objective To explore the potential of health registry information to enhance clinical risk assessment and stratification. Design Fixed cohort study including all registered patients with COPD in Catalonia (Spain) (7.5 million citizens) at 31 December 2014 with 1-year (2015) follow-up. Methods A total of 264 830 patients with COPD diagnosis, based on the International Classification of Diseases (Ninth Revision) coding, were assessed. Performance of multiple logistic regression models for the six main dependent variables of the study: mortality, hospitalisations (patients with one or more admissions; all cases and COPD-related), multiple hospitalisations (patients with at least two admissions; all causes and COPD-related) and users with high healthcare costs. Neither clinical nor forced spirometry data were available. Results Multimorbidity, assessed with the adjusted morbidity grouper, was the covariate with the highest impact in the predictive models, which in turn showed high performance measured by the C-statistics: (1) mortality (0.83), (2 and 3) hospitalisations (all causes: 0.77; COPD-related: 0.81), (4 and 5) multiple hospitalisations (all causes: 0.80; COPD-related: 0.87) and (6) users with high healthcare costs (0.76). Fifteen per cent of individuals with highest healthcare costs to year ratio represented 59% of the overall costs of patients with COPD. Conclusions The results stress the impact of assessing multimorbidity with the adjusted morbidity grouper on considered health indicators, which has implications for enhanced COPD staging and clinical management. Trial registration number NCT02956395. PMID:29511004

  6. Antecedents of Coping with the Disease in Patients with Multiple Sclerosis: A Qualitative Content Analysis.

    Science.gov (United States)

    Dehghani, Ali; Dehghan Nayeri, Nahid; Ebadi, Abbas

    2017-01-01

    Due to many physical and mental disorders that occur in multiple sclerosis patients, identifying the factors affecting coping based on the experiences of patients using qualitative study is essential to improve their quality of life. This study was conducted to explore the antecedents of coping with the disease in patients with multiple sclerosis. This is a qualitative study conducted on 11 patients with multiple sclerosis in 2015 in Tehran, Iran. These patients were selected based on purposive sampling. Data were collected using semi-structured and in-depth interviews and coded. These data were analyzed using the conventional content analysis. The rigor of qualitative data using the criteria proposed by Guba and Lincoln were assessed. Five main categories were revealed: (1) social support, (2) lenience, (3) reliance on faith, (4) knowledge of multiple sclerosis and modeling, and (5) economic and environmental situation. Each category had several distinct sub-categories. The results of this study showed that coping with multiple sclerosis is a complex, multidimensional and contextual concept that is affected by various factors in relation to the context of Iran. The findings of the study can provide the healthcare professionals with deeper recognition and understanding of these antecedents to improve successful coping in Iranian patients suffering from multiple sclerosis.

  7. Use of the 2010 McDonald criteria can facilitate early diagnosis of pediatric multiple sclerosis in a predominantly black cohort.

    Science.gov (United States)

    Williams, Mitchel T; Tapos, Daniela O; Juhász, Csaba

    2014-12-01

    Pediatric-onset multiple sclerosis represents around 3-5% of all patients with multiple sclerosis. Both the 2005 and 2010 McDonald criteria for multiple sclerosis have been suggested for the possible use in pediatric-onset multiple sclerosis. Modifications incorporated into the 2010 criteria enabled the fulfillment of dissemination in time to be met with the initial magnetic resonance imaging. The present study was designed to compare the diagnostic sensitivity of these criteria at initial presentation, the time to fulfilling them, and secondary effects of ethnicity in pediatric-onset multiple sclerosis. Twenty-five children with clinically definite multiple sclerosis (mean age, 14.6 ± 3.1 years; 15 girls) from a single center between 2005 and 2012 were analyzed using both the 2005 and 2010 McDonald criteria based on initial clinical presentation and neuroimaging findings comparing diagnostic sensitivity, time interval to meet diagnosis, and ethnicity. Initial multiple sclerosis diagnosis rates applying the 2005 McDonald criteria were 32% compared with 92% for the 2010 criteria (P = 0.0003). The mean time after initial signs until the 2005 and 2010 McDonald criteria for multiple sclerosis were met was 5.0 vs 0.7 months, respectively (P = 0.001). Time to diagnosis using the 2010 criteria was shorter in black children than the European white (P = 0.005). The 2010 McDonald criteria are an appropriate tool for the timely diagnosis of pediatric multiple sclerosis, especially in black children, potentially allowing an earlier initiation of disease-modifying therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Prenatal exposure to multiple pesticides is associated with auditory brainstem response at 9months in a cohort study of Chinese infants.

    Science.gov (United States)

    Sturza, Julie; Silver, Monica K; Xu, Lin; Li, Mingyan; Mai, Xiaoqin; Xia, Yankai; Shao, Jie; Lozoff, Betsy; Meeker, John

    2016-01-01

    Pesticides are associated with poorer neurodevelopmental outcomes, but little is known about the effects on sensory functioning. Auditory brainstem response (ABR) and pesticide data were available for 27 healthy, full-term 9-month-old infants participating in a larger study of early iron deficiency and neurodevelopment. Cord blood was analyzed by gas chromatography-mass spectrometry for levels of 20 common pesticides. The ABR forward-masking condition consisted of a click stimulus (masker) delivered via ear canal transducers followed by an identical stimulus delayed by 8, 16, or 64 milliseconds (ms). ABR peak latencies were evaluated as a function of masker-stimulus time interval. Shorter wave latencies reflect faster neural conduction, more mature auditory pathways, and greater degree of myelination. Linear regression models were used to evaluate associations between total number of pesticides detected and ABR outcomes. We considered an additive or synergistic effect of poor iron status by stratifying our analysis by newborn ferritin (based on median split). Infants in the sample were highly exposed to pesticides; a mean of 4.1 pesticides were detected (range 0-9). ABR Wave V latency and central conduction time (CCT) were associated with the number of pesticides detected in cord blood for the 64ms and non-masker conditions. A similar pattern seen for CCT from the 8ms and 16ms conditions, although statistical significance was not reached. Increased pesticide exposure was associated with longer latency. The relation between number of pesticides detected in cord blood and CCT depended on the infant's cord blood ferritin level. Specifically, the relation was present in the lower cord blood ferritin group but not the higher cord blood ferritin group. ABR processing was slower in infants with greater prenatal pesticide exposure, indicating impaired neuromaturation. Infants with lower cord blood ferritin appeared to be more sensitive to the effects of prenatal pesticide

  9. Analytical multiple scattering correction to the Mie theory: Application to the analysis of the lidar signal

    Science.gov (United States)

    Flesia, C.; Schwendimann, P.

    1992-01-01

    The contribution of the multiple scattering to the lidar signal is dependent on the optical depth tau. Therefore, the radar analysis, based on the assumption that the multiple scattering can be neglected is limited to cases characterized by low values of the optical depth (tau less than or equal to 0.1) and hence it exclude scattering from most clouds. Moreover, all inversion methods relating lidar signal to number densities and particle size must be modified since the multiple scattering affects the direct analysis. The essential requests of a realistic model for lidar measurements which include the multiple scattering and which can be applied to practical situations follow. (1) Requested are not only a correction term or a rough approximation describing results of a certain experiment, but a general theory of multiple scattering tying together the relevant physical parameter we seek to measure. (2) An analytical generalization of the lidar equation which can be applied in the case of a realistic aerosol is requested. A pure analytical formulation is important in order to avoid the convergency and stability problems which, in the case of numerical approach, are due to the large number of events that have to be taken into account in the presence of large depth and/or a strong experimental noise.

  10. Heritability analysis of surface-based cortical thickness estimation on a large twin cohort

    Science.gov (United States)

    Shen, Kaikai; Doré, Vincent; Rose, Stephen; Fripp, Jurgen; McMahon, Katie L.; de Zubicaray, Greig I.; Martin, Nicholas G.; Thompson, Paul M.; Wright, Margaret J.; Salvado, Olivier

    2015-03-01

    The aim of this paper is to assess the heritability of cerebral cortex, based on measurements of grey matter (GM) thickness derived from structural MR images (sMRI). With data acquired from a large twin cohort (328 subjects), an automated method was used to estimate the cortical thickness, and EM-ICP surface registration algorithm was used to establish the correspondence of cortex across the population. An ACE model was then employed to compute the heritability of cortical thickness. Heritable cortical thickness measures various cortical regions, especially in frontal and parietal lobes, such as bilateral postcentral gyri, superior occipital gyri, superior parietal gyri, precuneus, the orbital part of the right frontal gyrus, right medial superior frontal gyrus, right middle occipital gyrus, right paracentral lobule, left precentral gyrus, and left dorsolateral superior frontal gyrus.

  11. Fruit and vegetables consumption and incident hypertension: dose-response meta-analysis of prospective cohort studies.

    Science.gov (United States)

    Wu, L; Sun, D; He, Y

    2016-10-01

    The role of dietary factors on chronic diseases seems essential in the potentially adverse or preventive effects. However, no evidence of dose-response meta-analysis of prospective cohort studies has verified the association between the intake of fruit and/or vegetables and the risk of developing hypertension. The PubMed and Embase were searched for prospective cohort studies. A generic inverse-variance method with random effects model was used to calculate the pooled relative risks (RRs) and 95% confidence intervals (CIs). Generalized least squares trend estimation model was used to calculate the study-specific slopes for the dose-response analyses. Seven articles comprised nine cohorts involving 185 676 participants were assessed. The highest intake of fruit or vegetables separately, and total fruit and vegetables were inversely associated with the incident risk of hypertension compared with the lowest level, and the pooled RRs and 95% CIs were 0.87 (0.79, 0.95), 0.88 (0.79, 0.99) and 0.90 (0.84, 0.98), respectively. We also found an inverse dose-response relation between the risk of developing hypertension and fruit intake, and total fruit and vegetables consumption. The incident risk of hypertension was decreased by 1.9% for each serving per day of fruit consumption, and decreased by 1.2% for each serving per day of total fruit and vegetables consumption. Our results support the recommendation to increase the consumption of fruit and vegetables with respect to preventing the risk of developing hypertension. However, further large prospective studies and long-term high-quality randomized controlled trials are still needed to confirm the observed association.

  12. Mortality of colorectal cancer in Taiwan, 1971-2010: temporal changes and age-period-cohort analysis.

    Science.gov (United States)

    Su, Shih-Yung; Huang, Jing-Yang; Jian, Zhi-Hong; Ho, Chien-Chang; Lung, Chia-Chi; Liaw, Yung-Po

    2012-12-01

    Colorectal cancer (CRC) is the second most common cause of cancer death in developed countries among men (after lung cancer) and the third most common among women. This study thus examines the long-term trends of CRC mortality in Taiwan. CRC cases were collective between patients aged 30 years or older and younger than 85 years from the Taiwan death registries during 1971-2010. Standard descriptive techniques such as age-standardized mortality rates (ASMR), aural percent change, and age-period-cohort analyses were used. The increase of percentage change by each age group in men was higher than in women. The ASMR of CRC increased 2-fold for men and almost 1.5-fold for women during the periods 1971-1975 and 2006-2010. For age-period-cohort analysis, the estimated mortality rate increased steadily with age in both sexes, and plateaued at 175.29 per 100,000 people for men and 128.14 per 100,000 for women in the 80- to 84-year-old group. Period effects were weak in both sexes. Cohort effects were strong. Between 30 and 59 years of age, the sex ratio showed that the female CRC mortality rate was higher than that of their male counterparts. Conversely, the mortality risk of CRC in men was higher than that in women when they were between 60 and 84 years old. The current findings showed a consistent increase in mortality from CRC over the years. Changes in the patient sex ratio indicated an important etiological role of sex hormones, especially in women aged 60 years or younger.

  13. Adult lung function and long-term air pollution exposure. ESCAPE: a multicentre cohort study and meta-analysis

    Science.gov (United States)

    Adam, Martin; Schikowski, Tamara; Carsin, Anne Elie; Cai, Yutong; Jacquemin, Benedicte; Sanchez, Margaux; Vierkötter, Andrea; Marcon, Alessandro; Keidel, Dirk; Sugiri, Dorothee; Al Kanani, Zaina; Nadif, Rachel; Siroux, Valérie; Hardy, Rebecca; Kuh, Diana; Rochat, Thierry; Bridevaux, Pierre-Olivier; Eeftens, Marloes; Tsai, Ming-Yi; Villani, Simona; Phuleria, Harish Chandra; Birk, Matthias; Cyrys, Josef; Cirach, Marta; de Nazelle, Audrey; Nieuwenhuijsen, Mark J.; Forsberg, Bertil; de Hoogh, Kees; Declerq, Christophe; Bono, Roberto; Piccioni, Pavilio; Quass, Ulrich; Heinrich, Joachim; Jarvis, Deborah; Pin, Isabelle; Beelen, Rob; Hoek, Gerard; Brunekreef, Bert; Schindler, Christian; Sunyer, Jordi; Krämer, Ursula; Kauffmann, Francine; Hansell, Anna L.; Künzli, Nino; Probst-Hensch, Nicole

    2015-01-01

    The chronic impact of ambient air pollutants on lung function in adults is not fully understood. The objective of this study was to investigate the association of long-term exposure to ambient air pollution with lung function in adult participants from five cohorts in the European Study of Cohorts for Air Pollution Effects (ESCAPE). Residential exposure to nitrogen oxides (NO2, NOx) and particulate matter (PM) was modelled and traffic indicators were assessed in a standardised manner. The spirometric parameters forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) from 7613 subjects were considered as outcomes. Cohort-specific results were combined using meta-analysis. We did not observe an association of air pollution with longitudinal change in lung function, but we observed that a 10 μg·m−3 increase in NO2 exposure was associated with lower levels of FEV1 (−14.0 mL, 95% CI −25.8 to −2.1) and FVC (−14.9 mL, 95% CI −28.7 to −1.1). An increase of 10 μg·m−3 in PM10, but not other PM metrics (PM2.5, coarse fraction of PM, PM absorbance), was associated with a lower level of FEV1 (−44.6 mL, 95% CI −85.4 to −3.8) and FVC (−59.0 mL, 95% CI −112.3 to −5.6). The associations were particularly strong in obese persons. This study adds to the evidence for an adverse association of ambient air pollution with lung function in adults at very low levels in Europe. PMID:25193994

  14. Colorectal cancer mortality trends in Serbia during 1991-2010: an age-period-cohort analysis and a joinpoint regression analysis.

    Science.gov (United States)

    Ilic, Milena; Ilic, Irena

    2016-06-22

    For both men and women worldwide, colorectal cancer is among the leading causes of cancer-related death. This study aimed to assess the mortality trends of colorectal cancer in Serbia between 1991 and 2010, prior to the introduction of population-based screening. Joinpoint regression analysis was used to estimate average annual percent change (AAPC) with the corresponding 95% confidence interval (CI). Furthermore, age-period-cohort analysis was performed to examine the effects of birth cohort and calendar period on the observed temporal trends. We observed a significantly increased trend in colorectal cancer mortality in Serbia during the study period (AAPC = 1.6%, 95% CI 1.3%-1.8%). Colorectal cancer showed an increased mortality trend in both men (AAPC = 2.0%, 95% CI 1.7%-2.2%) and women (AAPC = 1.0%, 95% CI 0.6%-1.4%). The temporal trend of colorectal cancer mortality was significantly affected by birth cohort (P < 0.05), whereas the study period did not significantly affect the trend (P = 0.072). Colorectal cancer mortality increased for the first several birth cohorts in Serbia (from 1916 to 1955), followed by downward flexion for people born after the 1960s. According to comparability test, overall mortality trends for colon cancer and rectal and anal cancer were not parallel (the final selected model rejected parallelism, P < 0.05). We found that colorectal cancer mortality in Serbia increased considerably over the past two decades. Mortality increased particularly in men, but the trends were different according to age group and subsite. In Serbia, interventions to reduce colorectal cancer burden, especially the implementation of a national screening program, as well as treatment improvements and measures to encourage the adoption of a healthy lifestyle, are needed.

  15. Mortality in the French TRACY cohort of uranium cycle workers

    International Nuclear Information System (INIS)

    Nicolle-Mir, Laurence

    2016-01-01

    This first analysis of mortality in a new cohort of French uranium cycle workers observed a healthy worker effect, as shown by a large all-cause mortality deficit. The current reconstruction of exposure data (radiological, chemical, and physical) will make it possible to study the risks specific to internal uranium contamination in individuals exposed to multiple agents. (author)

  16. Neophyte experiences of football (soccer) match analysis: a multiple case study approach.

    Science.gov (United States)

    McKenna, Mark; Cowan, Daryl Thomas; Stevenson, David; Baker, Julien Steven

    2018-03-05

    Performance analysis is extensively used in sport, but its pedagogical application is little understood. Given its expanding role across football, this study explored the experiences of neophyte performance analysts. Experiences of six analysis interns, across three professional football clubs, were investigated as multiple cases of new match analysis. Each intern was interviewed after their first season, with archival data providing background information. Four themes emerged from qualitative analysis: (1) "building of relationships" was important, along with trust and role clarity; (2) "establishing an analysis system" was difficult due to tacit coach knowledge, but analysis was established; (3) the quality of the "feedback process" hinged on coaching styles, with balance of feedback and athlete engagement considered essential; (4) "establishing effect" was complex with no statistical effects reported; yet enhanced relationships, role clarity, and improved performances were reported. Other emic accounts are required to further understand occupational culture within performance analysis.

  17. Increasing mumps incidence rates among children and adolescents in the Republic of Korea: age–period–cohort analysis

    Directory of Open Access Journals (Sweden)

    Young-June Choe

    2017-04-01

    Conclusions: The increase in mumps seen in Korea may have been affected by the birth cohort exposed to the Rubini strain; however other factors may have contributed to the increase in non-exposed cohorts.

  18. MTHFR Glu429Ala and ERCC5 His46His polymorphisms are associated with prognosis in colorectal cancer patients: analysis of two independent cohorts from Newfoundland.

    Directory of Open Access Journals (Sweden)

    Amit A Negandhi

    Full Text Available In this study, 27 genetic polymorphisms that were previously reported to be associated with clinical outcomes in colorectal cancer patients were investigated in relation to overall survival (OS and disease free survival (DFS in colorectal cancer patients from Newfoundland.The discovery and validation cohorts comprised of 532 and 252 patients, respectively. Genotypes of 27 polymorphisms were first obtained in the discovery cohort and survival analyses were performed assuming the co-dominant genetic model. Polymorphisms associated with disease outcomes in the discovery cohort were then investigated in the validation cohort.When adjusted for sex, age, tumor stage and microsatellite instability (MSI status, four polymorphisms were independent predictors of OS in the discovery cohort MTHFR Glu429Ala (HR: 1.72, 95%CI: 1.04-2.84, p = 0.036, ERCC5 His46His (HR: 1.78, 95%CI: 1.15-2.76, p = 0.01, SERPINE1 -675indelG (HR: 0.52, 95%CI: 0.32-0.84, p = 0.008, and the homozygous deletion of GSTM1 gene (HR: 1.4, 95%CI: 1.03-1.92, p = 0.033. In the validation cohort, the MTHFR Glu429Ala polymorphism was associated with shorter OS (HR: 1.71, 95%CI: 1.18-2.49, p = 0.005, although with a different genotype than the discovery cohort (CC genotype in the discovery cohort and AC genotype in the validation cohort. When stratified based on treatment with 5-Fluorouracil (5-FU-based regimens, this polymorphism was associated with reduced OS only in patients not treated with 5-FU. In the DFS analysis, when adjusted for other variables, the TT genotype of the ERCC5 His46His polymorphism was associated with shorter DFS in both cohorts (discovery cohort: HR: 1.54, 95%CI: 1.04-2.29, p = 0.032 and replication cohort: HR: 1.81, 95%CI: 1.11-2.94, p = 0.018.In this study, associations of the MTHFR Glu429Ala polymorphism with OS and the ERCC5 His46His polymorphism with DFS were identified in two colorectal cancer patient cohorts. Our results also suggest

  19. Combining MCDA and risk analysis: dealing with scaling issues in the multiplicative AHP

    DEFF Research Database (Denmark)

    Barfod, Michael Bruhn; van den Honert, Rob; Salling, Kim Bang

    the progression factor 2 is used for calculating scores of alternatives and √2 for calculation of criteria weights when transforming the verbal judgments stemming from pair wise comparisons. However, depending on the decision context, the decision-makers aversion towards risk, etc., it is most likely......This paper proposes a new decision support system (DSS) for applying risk analysis and stochastic simulation to the multiplicative AHP in order to deal with issues concerning the progression factors. The multiplicative AHP makes use of direct rating on a logarithmic scale, and for this purpose...

  20. DYNAMIC ANALYSIS OF A CRIMPING DEVICE WITH MULTIPLE CAMS USING MSC ADAMS II

    Directory of Open Access Journals (Sweden)

    Gheorghe Popescu

    2012-05-01

    Full Text Available Through the present paper, the author presents the results of the dynamic analysis with MSC ADAMS of the mechanism with a crimping device with 12 tightening cams, designed and used in the technological process of assembly of the indigenous electrical detonators. In this sense, the mechanism with multiple cams is considered a mechanical system and is treated as an assembly of rigid bodies connected by mechanical connections and elastic elements. For shaping and simulation of the mechanism with multiple cams using ADAMS program, the author got through the following stages: construction of the pattern, its testing and simulation, validation, finishing, parametrization, optimization of the pattern.

  1. Links between Bloom's Taxonomy and Gardener's Multiple Intelligences: The issue of Textbook Analysis

    Directory of Open Access Journals (Sweden)

    Mahmoud Abdi Tabari

    2015-02-01

    Full Text Available The major thrust of this research was to investigate the cognitive aspect of the high school textbooks and interchange series, due to their extensive use, through content analysis based on Bloom's taxonomy and Gardner's Multiple Intelligences (MI. This study embraced two perspectives in a grid in order to broaden and deepen the analysis by determining the numbers and the types of intelligences with respect to their learning objectives tapped in the textbooks and comparing them. Through codification of Bloom’s learning objectives and Gardner's MI, the results showed that there was a significant difference between the numbers of intelligences with respect to their learning objectives in the textbooks. However, the interchange series enjoyed a large number of the spatial and the interpersonal intelligences across eight levels of learning objectives, whereas they had the least number of the intrapersonal, the musical, and the bodily-kinesthetic intelligences across knowledge understanding and application levels. Keywords: learning objectives, multiple intelligences, textbook analysis

  2. Verification and implications of the multiple pin treatment in the SASSYS-1 LMR systems analysis code

    International Nuclear Information System (INIS)

    Dunn, F.E.

    1994-01-01

    As part of a program to obtain realistic, as opposed to excessively conservative, analysis of reactor transients, a multiple pin treatment for the analysis of intra-subassembly thermal hydraulics has been included in the SASSYS-1 liquid metal reactor systems analysis code. This new treatment has made possible a whole new level of verification for the code. The code can now predict the steady-state and transient responses of individual thermocouples within instrumented subassemlies in a reactor, rather than just predicting average temperatures for a subassembly. Very good agreement has been achieved between code predictions and the experimental measurements of steady-state and transient temperatures and flow rates in the Shutdown Heat Removal Tests in the EBR-II Reactor. Detailed multiple pin calculations for blanket subassemblies in the EBR-II reactor demonstrate that the actual steady-state and transient peak temperatures in these subassemblies are significantly lower than those that would be calculated by simpler models

  3. Pooling Data from Multiple Longitudinal Studies: The Role of Item Response Theory in Integrative Data Analysis

    Science.gov (United States)

    Curran, Patrick J.; Hussong, Andrea M.; Cai, Li; Huang, Wenjing; Chassin, Laurie; Sher, Kenneth J.; Zucker, Robert A.

    2010-01-01

    There are a number of significant challenges encountered when studying development over an extended period of time including subject attrition, changing measurement structures across group and developmental period, and the need to invest substantial time and money. Integrative data analysis is an emerging set of methodologies that overcomes many of the challenges of single sample designs through the pooling of data drawn from multiple existing developmental studies. This approach is characterized by a host of advantages, but this also introduces several new complexities that must be addressed prior to broad adoption by developmental researchers. In this paper we focus on methods for fitting measurement models and creating scale scores using data drawn from multiple longitudinal studies. We present findings from the analysis of repeated measures of internalizing symptomatology that were pooled from three existing developmental studies. We describe and demonstrate each step in the analysis and we conclude with a discussion of potential limitations and directions for future research. PMID:18331129

  4. Instantiating the multiple levels of analysis perspective in a program of study on externalizing behavior

    Science.gov (United States)

    Beauchaine, Theodore P.; Gatzke-Kopp, Lisa M.

    2014-01-01

    During the last quarter century, developmental psychopathology has become increasingly inclusive and now spans disciplines ranging from psychiatric genetics to primary prevention. As a result, developmental psychopathologists have extended traditional diathesis–stress and transactional models to include causal processes at and across all relevant levels of analysis. Such research is embodied in what is known as the multiple levels of analysis perspective. We describe how multiple levels of analysis research has informed our current thinking about antisocial and borderline personality development among trait impulsive and therefore vulnerable individuals. Our approach extends the multiple levels of analysis perspective beyond simple Biology × Environment interactions by evaluating impulsivity across physiological systems (genetic, autonomic, hormonal, neural), psychological constructs (social, affective, motivational), developmental epochs (preschool, middle childhood, adolescence, adulthood), sexes (male, female), and methods of inquiry (self-report, informant report, treatment outcome, cardiovascular, electrophysiological, neuroimaging). By conducting our research using any and all available methods across these levels of analysis, we have arrived at a developmental model of trait impulsivity that we believe confers a greater understanding of this highly heritable trait and captures at least some heterogeneity in key behavioral outcomes, including delinquency and suicide. PMID:22781868

  5. Cinteny: flexible analysis and visualization of synteny and genome rearrangements in multiple organisms

    Directory of Open Access Journals (Sweden)

    Meller Jaroslaw

    2007-03-01

    Full Text Available Abstract Background Identifying syntenic regions, i.e., blocks of genes or other markers with evolutionary conserved order, and quantifying evolutionary relatedness between genomes in terms of chromosomal rearrangements is one of the central goals in comparative genomics. However, the analysis of synteny and the resulting assessment of genome rearrangements are sensitive to the choice of a number of arbitrary parameters that affect the detection of synteny blocks. In particular, the choice of a set of markers and the effect of different aggregation strategies, which enable coarse graining of synteny blocks and exclusion of micro-rearrangements, need to be assessed. Therefore, existing tools and resources that facilitate identification, visualization and analysis of synteny need to be further improved to provide a flexible platform for such analysis, especially in the context of multiple genomes. Results We present a new tool, Cinteny, for fast identification and analysis of synteny with different sets of markers and various levels of coarse graining of syntenic blocks. Using Hannenhalli-Pevzner approach and its extensions, Cinteny also enables interactive determination of evolutionary relationships between genomes in terms of the number of rearrangements (the reversal distance. In particular, Cinteny provides: i integration of synteny browsing with assessment of evolutionary distances for multiple genomes; ii flexibility to adjust the parameters and re-compute the results on-the-fly; iii ability to work with user provided data, such as orthologous genes, sequence tags or other conserved markers. In addition, Cinteny provides many annotated mammalian, invertebrate and fungal genomes that are pre-loaded and available for analysis at http://cinteny.cchmc.org. Conclusion Cinteny allows one to automatically compare multiple genomes and perform sensitivity analysis for synteny block detection and for the subsequent computation of reversal distances

  6. Network meta-analysis of multiple outcome measures accounting for borrowing of information across outcomes.

    Science.gov (United States)

    Achana, Felix A; Cooper, Nicola J; Bujkiewicz, Sylwia; Hubbard, Stephanie J; Kendrick, Denise; Jones, David R; Sutton, Alex J

    2014-07-21

    Network meta-analysis (NMA) enables simultaneous comparison of multiple treatments while preserving randomisation. When summarising evidence to inform an economic evaluation, it is important that the analysis accurately reflects the dependency structure within the data, as correlations between outcomes may have implication for estimating the net benefit associated with treatment. A multivariate NMA offers a framework for evaluating multiple treatments across multiple outcome measures while accounting for the correlation structure between outcomes. The standard NMA model is extended to multiple outcome settings in two stages. In the first stage, information is borrowed across outcomes as well across studies through modelling the within-study and between-study correlation structure. In the second stage, we make use of the additional assumption that intervention effects are exchangeable between outcomes to predict effect estimates for all outcomes, including effect estimates on outcomes where evidence is either sparse or the treatment had not been considered by any one of the studies included in the analysis. We apply the methods to binary outcome data from a systematic review evaluating the effectiveness of nine home safety interventions on uptake of three poisoning prevention practices (safe storage of medicines, safe storage of other household products, and possession of poison centre control telephone number) in households with children. Analyses are conducted in WinBUGS using Markov Chain Monte Carlo (MCMC) simulations. Univariate and the first stage multivariate models produced broadly similar point estimates of intervention effects but the uncertainty around the multivariate estimates varied depending on the prior distribution specified for the between-study covariance structure. The second stage multivariate analyses produced more precise effect estimates while enabling intervention effects to be predicted for all outcomes, including intervention effects on

  7. Prognostic value of platelet-to-lymphocyte ratio in pancreatic cancer: a comprehensive meta-analysis of 17 cohort studies.

    Science.gov (United States)

    Zhou, Yongping; Cheng, Sijin; Fathy, Abdel Hamid; Qian, Haixin; Zhao, Yongzhao

    2018-01-01

    Several studies were conducted to explore the prognostic value of platelet-to-lymphocyte ratio (PLR) in pancreatic cancer and have reported contradictory results. This study aims to summarize the prognostic role of PLR in pancreatic cancer. Embase, PubMed and Cochrane Library were completely searched. The cohort studies focusing on the prognostic role of PLR in pancreatic cancer were eligible. The overall survival (OS) and progression-free survival (PFS) were analyzed. Fifteen papers containing 17 cohort studies with pancreatic cancer were identified. The results showed patients that with low PLR might have longer OS when compared to the patients with high PLR (hazard ratio=1.28, 95% CI=1.17-1.40, P analysis model, ethnicity, sample size and cut-off value. Further analyses based on the adjusted potential confounders were conducted, including CA199, neutrophil-to-lymphocyte ratio, modified Glasgow Prognostic Score, albumin, C-reactive protein, Eastern Cooperative Oncology Group, stage, tumor size, nodal involvement, tumor differentiation, margin status, age and gender, which confirmed that low PLR was a protective factor in pancreatic cancer. In addition, low PLR was significantly associated with longer PFS when compared to high PLR in pancreatic cancer (hazard ratio=1.27, 95% CI=1.03-1.57, P =0.03; I 2 =33%). In conclusion, it was found that high PLR is an unfavorable predictor of OS and PFS in patients with pancreatic cancer, and PLR is a promising prognostic biomarker for pancreatic cancer.

  8. Multiple Regression Analysis of Unconfined Compression Strength of Mine Tailings Matrices

    Directory of Open Access Journals (Sweden)

    Mahmood Ali A.

    2017-01-01

    Full Text Available As part of a novel approach of sustainable development of mine tailings, experimental and numerical analysis is carried out on newly formulated tailings matrices. Several physical characteristic tests are carried out including the unconfined compression strength test to ascertain the integrity of these matrices when subjected to loading. The current paper attempts a multiple regression analysis of the unconfined compressive strength test results of these matrices to investigate the most pertinent factors affecting their strength. Results of this analysis showed that the suggested equation is reasonably applicable to the range of binder combinations used.

  9. Failure analysis of high strength pipeline with single and multiple corrosions

    International Nuclear Information System (INIS)

    Chen, Yanfei; Zhang, Hong; Zhang, Juan; Li, Xin; Zhou, Jing

    2015-01-01

    Highlights: • We study failure of high strength pipelines with single corrosion. • We give regression equations for failure pressure prediction. • We propose assessment procedure for pipelines with multiple corrosions. - Abstract: Corrosion will compromise safety operation of oil and gas pipelines, accurate determination of failure pressure finds importance in residual strength assessment and corrosion allowance design of onshore and offshore pipelines. This paper investigates failure pressure of high strength pipeline with single and multiple corrosions using nonlinear finite element analysis. On the basis of developed regression equations for failure pressure prediction of high strength pipeline with single corrosion, the paper proposes an assessment procedure for predicting failure pressure of high strength pipeline with multiple corrosions. Furthermore, failure pressures predicted by proposed solutions are compared with experimental results and various assessment methods available in literature, where accuracy and versatility are demonstrated

  10. Analysis of γ spectra in airborne radioactivity measurements using multiple linear regressions

    International Nuclear Information System (INIS)

    Bao Min; Shi Quanlin; Zhang Jiamei

    2004-01-01

    This paper describes the net peak counts calculating of nuclide 137 Cs at 662 keV of γ spectra in airborne radioactivity measurements using multiple linear regressions. Mathematic model is founded by analyzing every factor that has contribution to Cs peak counts in spectra, and multiple linear regression function is established. Calculating process adopts stepwise regression, and the indistinctive factors are eliminated by F check. The regression results and its uncertainty are calculated using Least Square Estimation, then the Cs peak net counts and its uncertainty can be gotten. The analysis results for experimental spectrum are displayed. The influence of energy shift and energy resolution on the analyzing result is discussed. In comparison with the stripping spectra method, multiple linear regression method needn't stripping radios, and the calculating result has relation with the counts in Cs peak only, and the calculating uncertainty is reduced. (authors)

  11. Price competition and equilibrium analysis in multiple hybrid channel supply chain

    Science.gov (United States)

    Kuang, Guihua; Wang, Aihu; Sha, Jin

    2017-06-01

    The amazing boom of Internet and logistics industry prompts more and more enterprises to sell commodity through multiple channels. Such market conditions make the participants of multiple hybrid channel supply chain compete each other in traditional and direct channel at the same time. This paper builds a two-echelon supply chain model with a single manufacturer and a single retailer who both can choose different channel or channel combination for their own sales, then, discusses the price competition and calculates the equilibrium price under different sales channel selection combinations. Our analysis shows that no matter the manufacturer and retailer choose same or different channel price to compete, the equilibrium price does not necessarily exist the equilibrium price in the multiple hybrid channel supply chain and wholesale price change is not always able to coordinate supply chain completely. We also present the sufficient and necessary conditions for the existence of equilibrium price and coordination wholesale price.

  12. Multiple-cohort genetic association study reveals CXCR6 as a new chemokine receptor involved in long-term nonprogression to AIDS

    Science.gov (United States)

    Limou, Sophie; Coulonges, Cédric; Herbeck, Joshua T.; van Manen, Daniëlle; An, Ping; Le Clerc, Sigrid; Delaneau, Olivier; Diop, Gora; Taing, Lieng; Montes, Matthieu; van't Wout, Angélique B.; Gottlieb, Geoffrey S.; Therwath, Amu; Rouzioux, Christine; Delfraissy, Jean-François; Lelièvre, Jean-Daniel; Lévy, Yves; Hercberg, Serge; Dina, Christian; Phair, John; Donfield, Sharyne; Goedert, James J.; Buchbinder, Susan; Estaquier, Jérôme; Schächter, François; Gut, Ivo; Froguel, Philippe; Mullins, James I.; Schuitemaker, Hanneke; Winkler, Cheryl; Zagury, Jean-François

    2010-01-01

    Background. The compilation of previous genomewide association studies of AIDS shows a major polymorphism in the HCP5 gene associated with both control of the viral load and long-term nonprogression (LTNP) to AIDS. Methods. To look for genetic variants that affect LTNP without necessary control of the viral load, we reanalyzed the genomewide data of the unique LTNP Genomics of Resistance to Immunodeficiency Virus (GRIV) cohort by excluding “elite controller” patients, who were controlling the viral load at very low levels (<100 copies/mL). Results. The rs2234358 polymorphism in the CXCR6 gene was the strongest signal (P = 2.5 × 10−7; odds ratio, 1.85) obtained for the genomewide association study comparing the 186 GRIV LTNPs who were not elite controllers with 697 uninfected control subjects. This association was replicated in 3 additional independent European studies, reaching genomewide significance of Pcombined = 9.7 × 10−10. This association with LTNP is independent of the combined CCR2-CCR5 locus and the HCP5 polymorphisms. Conclusion. The statistical significance, the replication, and the magnitude of the association demonstrate that CXCR6 is likely involved in the molecular etiology of AIDS and, in particular, in LTNP, emphasizing the power of extreme-phenotype cohorts. CXCR6 is a chemokine receptor that is known as a minor coreceptor in human immunodeficiency virus type 1 infection but could participate in disease progression through its role as a mediator of inflammation. PMID:20704485

  13. Treatment outcomes of MDR-tuberculosis patients in Brazil: a retrospective cohort analysis

    Directory of Open Access Journals (Sweden)

    Mayara Lisboa Bastos

    2017-11-01

    Full Text Available Abstract Background Multidrug-resistant tuberculosis (MDR-TB is a threat for the global TB epidemic control. Despite existing evidence that individualized treatment of MDR-TB is superior to standardized regimens, the latter are recommended in Brazil, mainly because drug-susceptibility tests (DST are often restricted to first-line drugs in public laboratories. We compared treatment outcomes of MDR-TB patients using standardized versus individualized regimens in Brazil, a high TB-burden, low resistance setting. Methods The 2007–2013 cohort of the national electronic database (SITE-TB, which records all special treatments including drug-resistance, was analysed. Patients classified as MDR-TB in SITE-TB were eligible. Treatment outcomes were classified as successful (cure/treatment completed or unsuccessful (failure/relapse/death/loss to follow-up. The odds for successful treatment according to type of regimen were controlled for demographic and clinical variables. Results Out of 4029 registered patients, we included 1972 recorded from 2010 to 2012, who had more complete outcome data. The overall success proportion was 60%. Success was more likely in non-HIV patients, sputum-negative at baseline, with unilateral disease and without prior DR-TB. Adjusted for these variables, those receiving standardized regimens had 2.7-fold odds of success compared to those receiving individualized treatments when failure/relapse were considered, and 1.4-fold odds of success when death was included as an unsuccessful outcome. When loss to follow-up was added, no difference between types of treatment was observed. Patients who used levofloxacin instead of ofloxacin had 1.5-fold odds of success. Conclusion In this large cohort of MDR-TB patients with a low proportion of successful outcomes, standardized regimens had superior efficacy than individualized regimens, when adjusted for relevant variables. In addition to the limitations of any retrospective observational

  14. Financial Strain, Parental Smoking, and the Great Recession: An Analysis of the UK Millennium Cohort Study.

    Science.gov (United States)

    McKenna, Caoimhe S; Law, Catherine; Pearce, Anna

    2017-11-07

    During the recent "Great Recession," many families in the United Kingdom experienced increased financial strain (FS). The aim of this study was to determine if increases in FS, occurring over the period of the "Great Recession," were associated with increased risks of persistent and relapsed tobacco use among parents. We analyzed the Millennium Cohort Study, a longitudinal study of 18819 children born in the United Kingdom between 2000 and 2002. Surveys at 7 (T1, 2008) and 11 years (T2, 2012) spanned the "Great Recession." Three measures of increased FS were defined; "became income poor" (self-reported household income dropped below the "poverty line" between T1 and T2); "developed difficulty managing" (parental report of being "financially comfortable" at T1 and finding it "difficult to manage" at T2); "felt worse off" (parental report of feeling financially "worse off" at T2, compared to T1). Poisson regression was used to estimate risk ratios (RR), adjusted RRs (aRR), and 95% confidence intervals for three outcomes: "persistent tobacco use," "new reported tobacco use," and "relapsed tobacco use." Parents in households which "became income poor" over the period of the "Great Recession" were significantly more likely to report "persistent tobacco use" (aRR = 2.17 [1.83-2.57]) or "new reported tobacco use" (aRR = 1.72 [1.04-2.83]). Ninety-five percent of "new reported tobacco users" had evidence of prior tobacco use suggesting the majority were "relapsed tobacco users." Similar patterns were seen for those who "developed difficulty managing" and "felt worse off." Increased tobacco use among financially strained families has the potential to widen inequalities and undermine the public health policies that have had positive impacts on tobacco consumption in the United Kingdom. While several studies have shown that FS is associated with a higher prevalence of tobacco use, heavier smoking, and relapsed tobacco use, most of this work used cross-sectional data and none

  15. The effect of a transition into poverty on child and maternal mental health: a longitudinal analysis of the UK Millennium Cohort Study.

    Science.gov (United States)

    Wickham, Sophie; Whitehead, Margaret; Taylor-Robinson, David; Barr, Ben

    2017-03-01

    Whether or not relative measures of income poverty effectively reflect children's life chances has been the focus of policy debates in the UK. Although poverty is associated with poor child and maternal mental health, few studies have assessed the effect of moving into poverty on mental health. To inform policy, we explore the association between transitions into poverty and subsequent mental health among children and their mothers. In this longtitudinal analysis, we used data from the UK Millennium Cohort Study, a large nationally representative cohort of children born in the UK between Sept 1, 2000, and Jan 11, 2002, who participated in five survey waves as they progressed from 9 months of age to 11 years of age. Our analysis included all children and mothers who were free from mental health problems and not in poverty when the children were aged 3 years. We only included singletons (ie, not twins or other multiple pregnancies) and children for whom the mother was the main respondent to the study. The main outcomes were child socioemotional behavioural problems (Strengths and Difficulties Questionnaire) at ages 5 years, 7 years, and 11 years and maternal psychological distress (Kessler 6 scale). Using discrete time-hazard models, we followed up families without mental health problems at baseline and estimated odds ratios for subsequent onset of maternal and child mental health problems associated with first transition into poverty, while adjusting for confounders, including employment transitions. We further assessed whether or not change in maternal mental health explained any effect on child mental health. Of the 6063 families in the UK Millennium Cohort study at 3 years who met our inclusion criteria, 844 (14%) had a new transition into poverty compared with 5219 (86%) who remained out of poverty. After adjustment for confounders, transition into poverty increased the odds of socioemotional behavioural problems in children (odds ratio 1·41 [95% CI 1·02-1·93

  16. Determinants of fracture risk in a UK-population-based cohort of older women: a cross-sectional analysis of the Cohort for Skeletal Health in Bristol and Avon (COSHIBA)

    OpenAIRE

    Clark, Emma M.; Gould, Virginia C.; Morrison, Leigh; Masud, Tahir; Tobias, Jon

    2011-01-01

    Background: identification of individuals with high fracture risk from within primary care is complex. It is likely that the true contribution of falls to fracture risk is underestimated. Methods: cross-sectional analysis of a population-based cohort of 3,200 post-menopausal women aged 73???4 years. Self-reported data were collected on fracture, osteoporosis clinical risk factors and falls/mobility risk factors. Self-reported falls were compared with recorded falls on GP computerised records....

  17. An integrated probabilistic risk analysis decision support methodology for systems with multiple state variables

    International Nuclear Information System (INIS)

    Sen, P.; Tan, John K.G.; Spencer, David

    1999-01-01

    Probabilistic risk analysis (PRA) methods have been proven to be valuable in risk and reliability analysis. However, a weak link seems to exist between methods for analysing risks and those for making rational decisions. The integrated decision support system (IDSS) methodology presented in this paper attempts to address this issue in a practical manner. In consists of three phases: a PRA phase, a risk sensitivity analysis (SA) phase and an optimisation phase, which are implemented through an integrated computer software system. In the risk analysis phase the problem is analysed by the Boolean representation method (BRM), a PRA method that can deal with systems with multiple state variables and feedback loops. In the second phase the results obtained from the BRM are utilised directly to perform importance and risk SA. In the third phase, the problem is formulated as a multiple objective decision making problem in the form of multiple objective reliability optimisation. An industrial example is included. The resultant solutions of a five objective reliability optimisation are presented, on the basis of which rational decision making can be explored

  18. [Complicated pleural infection: Analysis of 2 consecutive cohorts managed with a different policy].

    Science.gov (United States)

    Moral, L; Loeda, C; Gómez, F; Pena, M A; Martínez, M; Cerdán, J M; Lillo, L; Toral, T

    2016-01-01

    The treatment of complicated pleural infection (CPI) is controversial. Clinical guidelines recommend drainage, but with the lowest grade of evidence. Recent reports have observed good outcomes with antibiotics alone. We retrospectively compared the outcomes in two consecutive cohorts treated with different policies: the first treated according to pleural fluid charactersitics (2005-2009, interventional-prone, group 1) and the second according to clinical assessment (2010-2013, conservative-prone, group 2). The clinical records of all children treated for CPI in our hospital between 2005 and 2013 were thoroughly reviewed. Primary outcomes were the proportion of children drained and the length of hospital stay (LHS). One hundred and nine patients (64 group 1 and 45 group 2) were analyzed. A chest tube was placed in 83% of patients in group 1 and 47% in group 2 (Pdrain most children with CPI. Clinical trials are now needed to identify when a drainage procedure would be useful. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  19. Is temporary employment related to health status? Analysis of the Northern Swedish Cohort.

    Science.gov (United States)

    Waenerlund, Anna-Karin; Virtanen, Pekka; Hammarström, Anne

    2011-07-01

    The aim of this study was to investigate whether temporary employment was related to non-optimal self-rated health and psychological distress at age 42 after adjustment for the same indicators at age 30, and to analyze the effects of job insecurity, low cash margin and high job strain on this relationship. A subcohort of the Northern Swedish Cohort that was employed at the 2007 follow-up survey (n = 907, response rate of 94%) was analyzed using data from 1995 and 2007 questionnaires. Temporary employees had a higher risk of both non-optimal self-rated health and psychological distress. After adjustment for non-optimal self-rated health at age 30 and psychological distress at age 30 as well as for sociodemographic variables, the odds ratios decreased but remained significant. However, after adjustment for job insecurity, high job strain and low cash margin the odds ratio dropped for non-optimal self-rated health but remained significant for psychological distress. Temporary employment may have adverse effects on self-rated health and psychological health after adjustment for previous health status and sociodemographic variables. Our findings indicate that low cash margin and job insecurity may partially mediate the association between temporary employment and health status.

  20. Delivering tertiary centre specialty care to ALS patients via telemedicine: a retrospective cohort analysis.

    Science.gov (United States)

    Selkirk, Stephen M; Washington, Monique O; McClellan, Frances; Flynn, Broderick; Seton, Jacinta M; Strozewski, Richard

    2017-08-01

    This study was undertaken to determine if ALS patients evaluated via telemedicine received the same quality of care as patients evaluated by traditional face-to-face encounters. A retrospective cohort study design was used. Participants were patients diagnosed with ALS that received multidisciplinary care at the tertiary Cleveland VA ALS Centre between 1 March 2008- and 31 anuary 2015. Participants were not randomised, but chose telemedicine based on preference, disability level or distance from the clinic. Telemedicine in this study consisted of a video conferencing platform enabling remote rather than face-to-face encounters with participants. There was no significant association between receiving quality ALS care and the mode of care. There was a trend for telemedicine patients to utilise home health care less often than those that received clinic care (AOR 0.50; 95% CI 0.16-1.59). There was no significant difference in survival time between the two groups (log-rank test χ 2  = 3.62, df = 1, p = 0.05). Patients receiving telemedicine had a higher probability of remaining stable or having telemedicine (HR = 0.39, 95% CI = 0.16-0.93). Patients managed by telemedicine received the same quality of care and had similar outcomes to those patients seen via traditional face-to-face encounters. Telemedicine is an effective platform for delivering high quality tertiary ALS care.

  1. Implementing primary health care-based PMTCT interventions: operational perspectives from Muhima cohort analysis (Rwanda)

    Science.gov (United States)

    Bucagu, Maurice; Muganda, John

    2014-01-01

    Introduction In countries with high burden of HIV, major programmatic challenges have been identified to preventing new infections among children and scaling up of treatment for pregnant mothers. We initiated this study to examine operational approaches that were used to enhance implementation of PMTCT interventions in Muhima health Centre (Kigali/Rwanda) from 2007 to 2010. Methods The prospective cohort study was conducted at Muhima health centre. A sample size of 656 was the minimum number required for the study. The main outcome was cumulative incidence of mother - to - child transmission of HIV-1 measured at 6 weeks of life among live born children. Results Among the 679 live born babies and followed up in this study, the overall cumulative rate of HIV-1 mother - to - child transmission observed was 3.2% at 6 weeks of age after birth. Disclosure of HIV status to partner was significantly associated with HIV-1 status of infants at 6 weeks of age (non-disclosure of HIV status adjusted odds ratio [AOR] 4.68, CI 1.39 to 15.77, p. Conclusion The Muhima type of decentralized health facility offered an appropriate platform for implementation of PMTCT interventions, with the following operational features: family - centered approach; integrated service delivery for PMTCT/MCH interventions, task shifting; subsidized membership fees for people living with HIV, allowing for access to the community-based health insurance benefits. PMID:26113893

  2. Investigating ethnic variations in reporting of psychotic symptoms: a multiple-group confirmatory factor analysis of the Psychosis Screening Questionnaire.

    Science.gov (United States)

    Heuvelman, Hein; Nazroo, James; Rai, Dheeraj

    2018-03-12

    Epidemiological evidence suggests risk for psychosis varies with ethnicity in Western countries. However, there is little evidence to date on the cross-cultural validity of screening instruments used for such comparisons. Combining two existing UK population-based cohorts, we examined risk for reporting psychotic symptoms across White British (n = 3467), White Irish (n = 851), Caribbean (n = 1899), Indian (n = 2590), Pakistani (n = 1956) and Bangladeshi groups (n = 1248). We assessed the psychometric properties of the Psychosis Screening Questionnaire (PSQ) with a multiple-group confirmatory factor analysis, assessing the equivalence of factor loadings, response thresholds and residual variances in an analysis of measurement non-invariance. Compared with prevalence among British Whites (5.4%), the prevalence of self-reported psychotic symptoms was greater in the Caribbean group (12.7%, adjusted OR = 2.38 [95% CI 1.84-3.07]). Prevalence was also increased among Pakistani individuals (8.3%, adjusted OR = 1.36 [1.01-1.84]) although this difference was driven by a greater likelihood of reporting paranoid symptoms. PSQ items for thought interference, strange experience and hallucination were measured in equivalent ways across ethnic groups. However, our measurement models suggested that paranoid symptoms were measured less reliably among ethnic minorities than among British Whites and appeared to exaggerate latent differences between Pakistani and White British groups when measurement non-invariance was not accounted for. Notwithstanding evidence for measurement non-invariance, the greater risk for reporting psychotic symptoms among Caribbean individuals is unlikely to be an artefact of measurement. Greater residual variance in the recording of paranoid symptoms among ethnic minority respondents warrants caution in using this item to investigate ethnic variation in psychosis risk.

  3. Causal relationship between the AHSG gene and BMD through fetuin-A and BMI: multiple mediation analysis.

    Science.gov (United States)

    Sritara, C; Thakkinstian, A; Ongphiphadhanakul, B; Chailurkit, L; Chanprasertyothin, S; Ratanachaiwong, W; Vathesatogkit, P; Sritara, P

    2014-05-01

    Using mediation analysis, a causal relationship between the AHSG gene and bone mineral density (BMD) through fetuin-A and body mass index (BMI) mediators was suggested. Fetuin-A, a multifunctional protein of hepatic origin, is associated with bone mineral density. It is unclear if this association is causal. This study aimed at clarification of this issue. A cross-sectional study was conducted among 1,741 healthy workers from the Electricity Generating Authority of Thailand (EGAT) cohort. The alpha-2-Heremans-Schmid glycoprotein (AHSG) rs2248690 gene was genotyped. Three mediation models were constructed using seemingly unrelated regression analysis. First, the ln[fetuin-A] group was regressed on the AHSG gene. Second, the BMI group was regressed on the AHSG gene and the ln[fetuin-A] group. Finally, the BMD model was constructed by fitting BMD on two mediators (ln[fetuin-A] and BMI) and the independent AHSG variable. All three analyses were adjusted for confounders. The prevalence of the minor T allele for the AHSG locus was 15.2%. The AHSG locus was highly related to serum fetuin-A levels (P Multiple mediation analyses showed that AHSG was significantly associated with BMD through the ln[fetuin-A] and BMI pathway, with beta coefficients of 0.0060 (95% CI 0.0038, 0.0083) and 0.0030 (95% CI 0.0020, 0.0045) at the total hip and lumbar spine, respectively. About 27.3 and 26.0% of total genetic effects on hip and spine BMD, respectively, were explained by the mediation effects of fetuin-A and BMI. Our study suggested evidence of a causal relationship between the AHSG gene and BMD through fetuin-A and BMI mediators.

  4. Multiple Imputation of a Randomly Censored Covariate Improves Logistic Regression Analysis.

    Science.gov (United States)

    Atem, Folefac D; Qian, Jing; Maye, Jacqueline E; Johnson, Keith A; Betensky, Rebecca A

    2016-01-01

    Randomly censored covariates arise frequently in epidemiologic studies. The most commonly used methods, including complete case and single imputation or substitution, suffer from inefficiency and bias. They make strong parametric assumptions or they consider limit of detection censoring only. We employ multiple imputation, in conjunction with semi-parametric modeling of the censored covariate, to overcome these shortcomings and to facilitate robust estimation. We develop a multiple imputation approach for randomly censored covariates within the framework of a logistic regression model. We use the non-parametric estimate of the covariate distribution or the semiparametric Cox model estimate in the presence of additional covariates in the model. We evaluate this procedure in simulations, and compare its operating characteristics to those from the complete case analysis and a survival regression approach. We apply the procedures to an Alzheimer's study of the association between amyloid positivity and maternal age of onset of dementia. Multiple imputation achieves lower standard errors and higher power than the complete case approach under heavy and moderate censoring and is comparable under light censoring. The survival regression approach achieves the highest power among all procedures, but does not produce interpretable estimates of association. Multiple imputation offers a favorable alternative to complete case analysis and ad hoc substitution methods in the presence of randomly censored covariates within the framework of logistic regression.

  5. PBDE and HBCDD levels in blood from Dutch mothers and infants. Analysis of a Dutch Groningen infant cohort

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, J.; Linderholm, L.; Athanassiadis, I.; Bergman, Aa. [Dept. of Environmental Chemistry, Stockholm Univ. (Sweden); Meijer, L.; Sauer, P. [Dept. of Paediatrics, State Univ. Groningen (Netherlands)

    2004-09-15

    Brominated flame retardants (BFRs) are chemicals with a large industrial production and ubiquitous global use. The three major classes of BFRs produced worldwide are; tetrabromobisphenol A (TBBPA), three commercial mixtures of polybrominated diphenyl ethers (PBDEs), Deca-, Octa- and PentaBDE and hexabromocyclododecane (HBCDD). Several BFRs are, due to their lipophilicity and bioaccumulation properties, both expected and in reality found in wildlife and humans. The aim of this study was to establish a clean up method for HBCDD analysis in human serum, as well as to investigate levels of PBDEs and HBCDD in serum from mothers and infants from a Dutch cohort. A total of 90 human serum samples were analyzed. To the best of our knowledge, HBCDD has not been reported previously in humans, and PBDEs have not been reported in human serum from The Netherlands.

  6. "An empire lost but a province gained": a cohort analysis of British international retirement in the Algarve.

    Science.gov (United States)

    Williams, A M; Patterson, G

    1998-06-01

    "The growth of international retirement in the Algarve has coincided with a number of changes in the international framework for population mobility as well as in the nature of the Algarve [Portugal] as a destination area. Tourism development, which is intimately linked to subsequent retirement migration, is particularly important in this. This paper considers the nature of the link between cycles of migration and of development in recipient areas, in the context of the remarkable and relatively late development of the Algarve as an area of tourism and retirement.... Cohort analysis...provides the basis for an examination of changes over time in the socio-demographic profiles of the migrants, their motivations, their residential patterns and their integration." excerpt

  7. Risk factors for low birth weight according to the multiple logistic regression model. A retrospective cohort study in José María Morelos municipality, Quintana Roo, Mexico.

    Science.gov (United States)

    Franco Monsreal, José; Tun Cobos, Miriam Del Ruby; Hernández Gómez, José Ricardo; Serralta Peraza, Lidia Esther Del Socorro

    2018-01-17

    Low birth weight has been an enigma for science over time. There have been many researches on its causes and its effects. Low birth weight is an indicator that predicts the probability of a child surviving. In fact, there is an exponential relationship between weight deficit, gestational age, and perinatal mortality. Multiple logistic regression is one of the most expressive and versatile statistical instruments available for the analysis of data in both clinical and epidemiology settings, as well as in public health. To assess in a multivariate fashion the importance of 17 independent variables in low birth weight (dependent variable) of children born in the Mayan municipality of José María Morelos, Quintana Roo, Mexico. Analytical observational epidemiological cohort study with retrospective temporality. Births that met the inclusion criteria occurred in the "Hospital Integral Jose Maria Morelos" of the Ministry of Health corresponding to the Maya municipality of Jose Maria Morelos during the period from August 1, 2014 to July 31, 2015. The total number of newborns recorded was 1,147; 84 of which (7.32%) had low birth weight. To estimate the independent association between the explanatory variables (potential risk factors) and the response variable, a multiple logistic regression analysis was performed using the IBM SPSS Statistics 22 software. In ascending numerical order values of odds ratio > 1 indicated the positive contribution of explanatory variables or possible risk factors: "unmarried" marital status (1.076, 95% confidence interval: 0.550 to 2.104); age at menarche ≤ 12 years (1.08, 95% confidence interval: 0.64 to 1.84); history of abortion(s) (1.14, 95% confidence interval: 0.44 to 2.93); maternal weight < 50 kg (1.51, 95% confidence interval: 0.83 to 2.76); number of prenatal consultations ≤ 5 (1.86, 95% confidence interval: 0.94 to 3.66); maternal age ≥ 36 years (3.5, 95% confidence interval: 0.40 to 30.47); maternal age ≤ 19 years (3

  8. Mortality after exposure to polychlorinated biphenyls and polychlorinated dibenzofurans: a meta-analysis of two highly exposed cohorts.

    Science.gov (United States)

    Li, Ming-Chieh; Chen, Pau-Chung; Tsai, Pei-Chien; Furue, Masutaka; Onozuka, Daisuke; Hagihara, Akihito; Uchi, Hiroshi; Yoshimura, Takesumi; Guo, Yue Leon

    2015-09-15

    Both Yucheng and Yusho were events of accidental exposure to highly doses of polychlorinated biphenyls and dibenzofurans in Asian people. Mortality experiences caused by various diseases were reported in both cohorts with similar and dissimilar findings. We thus conducted a meta-analysis of two cohorts to reevaluate the effects of PCBs and PCDFs on major causes of mortalities. Two recently updated Yucheng and Yusho mortality studies were included. For selected diseases, standardized mortality ratios (SMR) and 95% confidence intervals (95% CI) were extracted. Meta-analyses were conducted using a random-effects model only when heterogeneity (I(2)  > 50% and/or p value <0.10 by the Q test) was not found. A total of 1,803 Yucheng subjects (male, N = 830; female, N = 973) with 48,751 person-years of follow-up and 1,664 Yusho subjects (male, N = 860; female, N = 804) with 50,773 person-years are included. An increase in all-cause mortality (pooled SMR=1.2, 95% CI: 1.1-1.3, I(2)  = 0.0%), all cancers (pooled SMR=1.3, 95% CI: 1.1-1.6, I(2)  = 0.0%), lung cancer (pooled SMR=1.7, 95% CI: 1.2-2.3, I(2) =0.0%), heart disease (pooled SMR=1.3, 95% CI: 1.0-1.7, I(2)  = 43.4%) and hepatic disease (pooled SMR=1.9, 95% CI: 1.3-2.8, I(2)  = 0.0%) were found in pooled males. Significant elevation from liver cancer was found in pooled females (pooled SMR=2.0, 95% CI: 1.1-3.6, I(2)  = 0.0%). This meta-analysis of Yucheng and Yusho cohorts showed similar elevation from all cancer, lung cancer, heart disease and hepatic disease mortalities in exposed men. Furthermore, a new finding of elevated liver cancer mortality in exposed women was identified. © 2015 UICC.

  9. Optical design of multi-multiple expander structure of laser gas analysis and measurement device

    Science.gov (United States)

    Fu, Xiang; Wei, Biao

    2018-03-01

    The installation and debugging of optical circuit structure in the application of carbon monoxide distributed laser gas analysis and measurement, there are difficult key technical problems. Based on the three-component expansion theory, multi-multiple expander structure with expansion ratio of 4, 5, 6 and 7 is adopted in the absorption chamber to enhance the adaptability of the installation environment of the gas analysis and measurement device. According to the basic theory of aberration, the optimal design of multi-multiple beam expander structure is carried out. By using image quality evaluation method, the difference of image quality under different magnifications is analyzed. The results show that the optical quality of the optical system with the expanded beam structure is the best when the expansion ratio is 5-7.

  10. Noninvasive spectral imaging of skin chromophores based on multiple regression analysis aided by Monte Carlo simulation

    Science.gov (United States)

    Nishidate, Izumi; Wiswadarma, Aditya; Hase, Yota; Tanaka, Noriyuki; Maeda, Takaaki; Niizeki, Kyuichi; Aizu, Yoshihisa

    2011-08-01

    In order to visualize melanin and blood concentrations and oxygen saturation in human skin tissue, a simple imaging technique based on multispectral diffuse reflectance images acquired at six wavelengths (500, 520, 540, 560, 580 and 600nm) was developed. The technique utilizes multiple regression analysis aided by Monte Carlo simulation for diffuse reflectance spectra. Using the absorbance spectrum as a response variable and the extinction coefficients of melanin, oxygenated hemoglobin, and deoxygenated hemoglobin as predictor variables, multiple regression analysis provides regression coefficients. Concentrations of melanin and total blood are then determined from the regression coefficients using conversion vectors that are deduced numerically in advance, while oxygen saturation is obtained directly from the regression coefficients. Experiments with a tissue-like agar gel phantom validated the method. In vivo experiments with human skin of the human hand during upper limb occlusion and of the inner forearm exposed to UV irradiation demonstrated the ability of the method to evaluate physiological reactions of human skin tissue.

  11. Cohort profile

    DEFF Research Database (Denmark)

    Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg

    2016-01-01

    PURPOSE: The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. PARTICIPANTS: MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts-the Norweg......PURPOSE: The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. PARTICIPANTS: MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts......-the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. FINDINGS TO DATE: Initial harmonisation of data from the 2 cohorts...... has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies...

  12. Hypofractionation vs Conventional Radiation Therapy for Newly Diagnosed Diffuse Intrinsic Pontine Glioma: A Matched-Cohort Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Janssens, Geert O., E-mail: g.janssens@rther.umcn.nl [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Jansen, Marc H. [Pediatric Oncology/Hematology, VU University Medical Center, Amsterdam (Netherlands); Lauwers, Selmer J. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Nowak, Peter J. [Department of Radiation Oncology, Erasmus Medical Centre, Rotterdam (Netherlands); Oldenburger, Foppe R. [Department of Radiation Oncology, Academic Medical Centre, Amsterdam (Netherlands); Bouffet, Eric [Department of Hematology/Oncology, The Hospital for Sick Children, University of Toronto, Toronto (Canada); Saran, Frank [Department of Pediatric Oncology, The Royal Marsden NHS Foundation Trust, Sutton (United Kingdom); Kamphuis-van Ulzen, Karin [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Lindert, Erik J. van [Department of Neurosurgery, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Schieving, Jolanda H. [Department of Neurology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Boterberg, Tom [Department of Radiation Oncology, Ghent University Hospital, Ghent (Belgium); Kaspers, Gertjan J. [Pediatric Oncology/Hematology, VU University Medical Center, Amsterdam (Netherlands); Span, Paul N.; Kaanders, Johannes H. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Gidding, Corrie E. [Department of Pediatric Oncology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Hargrave, Darren [Department of Oncology, Great Ormond Street Hospital, London (United Kingdom)

    2013-02-01

    Purpose: Despite conventional radiation therapy, 54 Gy in single doses of 1.8 Gy (54/1.8 Gy) over 6 weeks, most children with diffuse intrinsic pontine glioma (DIPG) will die within 1 year after diagnosis. To reduce patient burden, we investigated the role of hypofractionation radiation therapy given over 3 to 4 weeks. A 1:1 matched-cohort analysis with conventional radiation therapy was performed to assess response and survival. Methods and Materials: Twenty-seven children, aged 3 to 14, were treated according to 1 of 2 hypofractionation regimens over 3 to 4 weeks (39/3 Gy, n=16 or 44.8/2.8 Gy, n=11). All patients had symptoms for {<=}3 months, {>=}2 signs of the neurologic triad (cranial nerve deficit, ataxia, long tract signs), and characteristic features of DIPG on magnetic resonance imaging. Twenty-seven patients fulfilling the same diagnostic criteria and receiving at least 50/1.8 to 2.0 Gy were eligible for the matched-cohort analysis. Results: With hypofractionation radiation therapy, the overall survival at 6, 9, and 12 months was 74%, 44%, and 22%, respectively. Progression-free survival at 3, 6, and 9 months was 77%, 43%, and 12%, respectively. Temporary discontinuation of steroids was observed in 21 of 27 (78%) patients. No significant difference in median overall survival (9.0 vs 9.4 months; P=.84) and time to progression (5.0 vs 7.6 months; P=.24) was observed between hypofractionation vs conventional radiation therapy, respectively. Conclusions: For patients with newly diagnosed DIPG, a hypofractionation regimen, given over 3 to 4 weeks, offers equal overall survival with less treatment burden compared with a conventional regimen of 6 weeks.

  13. Work Disability among Employees with Diabetes: Latent Class Analysis of Risk Factors in Three Prospective Cohort Studies.

    Directory of Open Access Journals (Sweden)

    Marianna Virtanen

    Full Text Available Studies of work disability in diabetes have examined diabetes as a homogeneous disease. We sought to identify subgroups among persons with diabetes based on potential risk factors for work disability.Participants were 2,445 employees with diabetes from three prospective cohorts (the Finnish Public Sector study, the GAZEL study, and the Whitehall II study. Work disability was ascertained via linkage to registers of sickness absence and disability pensions during a follow-up of 4 years. Study-specific latent class analysis was used to identify subgroups according to prevalent comorbid disease and health-risk behaviours. Study-specific associations with work disability at follow-up were pooled using fixed-effects meta-analysis.Separate latent class analyses for men and women in each cohort supported a two-class solution with one subgroup (total n = 1,086; 44.4% having high prevalence of chronic somatic diseases, psychological symptoms, obesity, physical inactivity and abstinence from alcohol and the other subgroup (total n = 1,359; 55.6% low prevalence of these factors. In the adjusted meta-analyses, participants in the 'high-risk' group had more work disability days (pooled rate ratio = 1.66, 95% CI 1.38-1.99 and more work disability episodes (pooled rate ratio = 1.33, 95% CI 1.21-1.46. These associations were similar in men and women, younger and older participants, and across occupational groups.Diabetes is not a homogeneous disease in terms of work disability risk. Approximately half of people with diabetes are assigned to a subgroup characterised by clustering of comorbid health conditions, obesity, physical inactivity, abstinence of alcohol, and associated high risk of work disability; the other half to a subgroup characterised by a more favourable risk profile.

  14. Analysis of antibody and cytokine markers for leprosy nerve damage and reactions in the INFIR cohort in India.

    Directory of Open Access Journals (Sweden)

    Rupendra Jadhav

    2011-03-01

    Full Text Available The ILEP Nerve Function Impairment in Reaction (INFIR is a cohort study designed to identify predictors of reactions and nerve function impairment (NFI in leprosy.Antibodies to mycobacteria, nerve components and serum cytokine were measured as potential markers for their possible association with reactions and NFI.303 newly diagnosed leprosy patients from two centres in North India were enrolled. Antibodies to PGL-1, LAM (IgG1 and IgG3, ceramide, S100 and TNFα levels were measured using ELISA techniques.S-100, PGL IgG and IgM antibody levels were lowest in patients with BT leprosy and highest in patients with lepromatous leprosy. LAM IgG1 and LAM IgG3 antibody levels were highest in patients with BL leprosy. Ceramide antibody levels were not correlated with type of leprosy. Levels of all the antibodies tested and TNF α were lowest in patients with only skin reaction. PGL IgM antibody levels were elevated in patients with skin reactions and NFI. Old sensory NFI is associated with significant elevation of PGL IgG, LAM IgG and S100 antibody levels.These results reveal that the antibody response to mycobacterial antigens, nerve antigens and cytokines are in a dynamic flux and could collectively contribute to NFI in leprosy. The association of multiple markers with old NFI may indicate the contribution of different pathological processes.

  15. Análisis edad-periodo-cohorte de la mortalidad por accidentes de tráfico en España Age-period-cohort analysis of traffic accident mortality in Spain

    Directory of Open Access Journals (Sweden)

    Carmen Saiz-Sánchez

    1999-05-01

    Full Text Available OBJETIVO. Estudiar la evolución de la mortalidad por accidentes de tráfico en España y su posible aplicación a un modelo edad-periodo-cohorte, así como el efecto que pueden tener algunas medidas de seguridad vial seleccionadas. MATERIAL Y MÉTODOS. Se obtuvieron las tasas de mortalidad por accidentes de tráfico y las tasas en intervalos quinquenales de edad para cada sexo, lo que permite su estudio como tasas específicas de edad por cohortes de nacimiento. Para determinar la asociación entre las medidas de seguridad vial seleccionadas y la mortalidad se han construido modelos de regresión de Poisson. RESULTADOS. Se observaron dos ondas evolutivas en la mortalidad por accidentes de tráfico. Respecto a la edad, no podemos hablar de un efecto claro; tampoco se encontró un efecto cohorte ni para varones ni para mujeres. En relación con las medidas de seguridad vial, se discutió la consistencia que guardaban los modelos seleccionados con los resultados gráficos, y se obtuvo que el uso obligatorio del casco y de las luces de cruce en motocicletas se ha asociado significativamente a la reducción de la mortalidad (RR 0.73, pOBJECTIVE. To study the evolution of traffic accidents mortality in Spain and its possible application to an age-period-cohort analysis, as well as the effect of selected road safety measures. MATERIAL AND METHODS. Road accidents rates of mortality were obtained, and five-year interval age rates for each sex, which allows the study of specific rates of age by birth cohorts. To determine the association between the selected road safety measures and mortality, Poisson regression models were adjusted. RESULTS. Two waves emerge in the evolution of traffic accidents. There was no clear effect with respect to age, nor was there a cohort effect for men or women. As to the road safety measures, we discuss the consistency between the selected models and graphic results. The compulsory use of helmet and of crossing lights is

  16. Risk factor screening to identify women requiring oral glucose tolerance testing to diagnose gestational diabetes: A systematic review and meta-analysis and analysis of two pregnancy cohorts.

    Directory of Open Access Journals (Sweden)

    Diane Farrar

    Full Text Available Easily identifiable risk factors including: obesity and ethnicity at high risk of diabetes are commonly used to indicate which women should be offered the oral glucose tolerance test (OGTT to diagnose gestational diabetes (GDM. Evidence regarding these risk factors is limited however. We conducted a systematic review (SR and meta-analysis and individual participant data (IPD analysis to evaluate the performance of risk factors in identifying women with GDM.We searched MEDLINE, Medline in Process, Embase, Maternity and Infant Care and the Cochrane Central Register of Controlled Trials (CENTRAL up to August 2016 and conducted additional reference checking. We included observational, cohort, case-control and cross-sectional studies reporting the performance characteristics of risk factors used to identify women at high risk of GDM. We had access to IPD from the Born in Bradford and Atlantic Diabetes in Pregnancy cohorts, all pregnant women in the two cohorts with data on risk factors and OGTT results were included.Twenty nine published studies with 211,698 women for the SR and a further 14,103 women from two birth cohorts (Born in Bradford and the Atlantic Diabetes in Pregnancy study for the IPD analysis were included. Six studies assessed the screening performance of guidelines; six examined combinations of risk factors; eight evaluated the number of risk factors and nine examined prediction models or scores. Meta-analysis using data from published studies suggests that irrespective of the method used, risk factors do not identify women with GDM well. Using IPD and combining risk factors to produce the highest sensitivities, results in low specificities (and so higher false positives. Strategies that use the risk factors of age (>25 or >30 and BMI (>25 or 30 perform as well as other strategies with additional risk factors included.Risk factor screening methods are poor predictors of which pregnant women will be diagnosed with GDM. A simple

  17. Genome-wide association study to identify common variants associated with brachial circumference: a meta-analysis of 14 cohorts.

    Directory of Open Access Journals (Sweden)

    Vesna Boraska

    Full Text Available Brachial circumference (BC, also known as upper arm or mid arm circumference, can be used as an indicator of muscle mass and fat tissue, which are distributed differently in men and women. Analysis of anthropometric measures of peripheral fat distribution such as BC could help in understanding the complex pathophysiology behind overweight and obesity. The purpose of this study is to identify genetic variants associated with BC through a large-scale genome-wide association scan (GWAS meta-analysis. We used fixed-effects meta-analysis to synthesise summary results across 14 GWAS discovery and 4 replication cohorts comprising overall 22,376 individuals (12,031 women and 10,345 men of European ancestry. Individual analyses were carried out for men, women, and combined across sexes using linear regression and an additive genetic model: adjusted for age and adjusted for age and BMI. We prioritised signals for follow-up in two-stages. We did not detect any signals reaching genome-wide significance. The FTO rs9939609 SNP showed nominal evidence for association (p<0.05 in the age-adjusted strata for men and across both sexes. In this first GWAS meta-analysis for BC to date, we have not identified any genome-wide significant signals and do not observe robust association of previously established obesity loci with BC. Large-scale collaborations will be necessary to achieve higher power to detect loci underlying BC.

  18. Patterns of zolpidem use among Iraq and Afghanistan veterans: A retrospective cohort analysis

    Science.gov (United States)

    Amuan, Megan E.; Jaramillo, Carlos A.; Eapen, Blessen C.

    2018-01-01

    Background Although concern exists regarding the adverse effects and rate of zolpidem use, especially long-term use, limited information is available concerning patterns of zolpidem use. Objective To examine the prevalence and correlates of zolpidem exposure in Iraq and Afghanistan Veterans (IAVs). Methods A retrospective cohort study of zolpidem prescriptions was performed with National Veterans Health Administration (VHA) data. We gathered national VA inpatient, outpatient, and pharmacy data files for IAV’s who received VA care between fiscal years (FY) 2013 and 2014. The VA pharmacy database was used to identify the prevalence of long term (>30 days), high-dose zolpidem exposure (>10mg immediate-release; >12.5mg extended-release) and other medications received in FY14. Baseline characteristics (demographics, diagnoses) were identified in FY13. Bivariate and multivariable analyses were used to examine the demographic, clinical, and medication correlates of zolpidem use. Results Of 493,683 IAVs who received VHA care in FY 2013 and 2014, 7.6% (n = 37,422) were prescribed zolpidem in FY 2014. Women had lower odds of high-dose zolpidem exposure than men. The majority (77.3%) of IAVs who received zolpidem prescriptions had long-term use with an average days’ supply of 189.3 days and a minority (0.9%) had high-dose exposure. In multivariable analyses, factors associated with long-term zolpidem exposure included age greater than 29 years old, PTSD, insomnia, Selim Index, physical 2–3 conditions, opioids, antidepressants, benzodiazepines, atypical antipsychotics, and stimulants. High dose exposure was associated with PTSD, depression, substance use disorder, insomnia, benzodiazepines, atypical antipsychotics, and stimulant prescriptions. Conclusion The current practices of insomnia pharmacotherapy in IAVs fall short of the clinical guidelines and may reflect high-risk zolpidem prescribing practices that put Iraq and Afghanistan Veterans at risk for adverse effects

  19. Mothers without companionship during childbirth: an analysis within the Millennium Cohort Study.

    Science.gov (United States)

    Essex, Holly N; Pickett, Kate E

    2008-12-01

    Studies have highlighted the benefits of social support during labor but no studies focused on women who choose to be unaccompanied or who have no companion available at birth. Our goals were, first, to identify characteristics of women who are unaccompanied at birth and compare these to those who had support and, second, to establish whether or not being unaccompanied at birth is a risk marker for adverse maternal and infant health outcomes. The sample comprised 16,610 natural mother-infant pairs, excluding women with planned cesarean sections in the Millennium Cohort Study. Multivariable regression models were used to examine, first, sociodemographic, cultural, socioeconomic, and pregnancy characteristics in relation to being unaccompanied and, second, being unaccompanied at birth in relation to labor and delivery outcomes, maternal health and health-related behaviors, parenting, and infant health and development. Mothers who were single (vs not single), multiparous (vs primiparous), of black or Pakistani ethnicity (vs white), from poor households (vs nonpoor), with low levels of education (vs high levels), and who did not attend antenatal classes (vs attenders) were at significantly higher risk of being unaccompanied at birth. Mothers unaccompanied at birth were more likely to have a preterm birth (vs term), an emergency cesarean section (vs spontaneous vaginal delivery) and spinal pain relief or a general anesthetic (vs no pain relief), a shorter labor, and lower satisfaction with life (vs high satisfaction) at 9 months postpartum. Their infants had significantly lower birthweight and were at higher risk of delayed gross motor development (vs normal development). Being unaccompanied at birth may be a useful marker of high-risk mothers and infants in need of additional support in the postpartum period and beyond.

  20. Mutations in complement regulatory proteins predispose to preeclampsia: a genetic analysis of the PROMISSE cohort.

    Directory of Open Access Journals (Sweden)

    Jane E Salmon

    2011-03-01

    Full Text Available Pregnancy in women with systemic lupus erythematosus (SLE or antiphospholipid antibodies (APL Ab--autoimmune conditions characterized by complement-mediated injury--is associated with increased risk of preeclampsia and miscarriage. Our previous studies in mice indicate that complement activation targeted to the placenta drives angiogenic imbalance and placental insufficiency.We use PROMISSE, a prospective study of 250 pregnant patients with SLE and/or APL Ab, to test the hypothesis in humans that impaired capacity to limit complement activation predisposes to preeclampsia. We sequenced genes encoding three complement regulatory proteins--membrane cofactor protein (MCP, complement factor I (CFI, and complement factor H (CFH--in 40 patients who had preeclampsia and found heterozygous mutations in seven (18%. Five of these patients had risk variants in MCP or CFI that were previously identified in atypical hemolytic uremic syndrome, a disease characterized by endothelial damage. One had a novel mutation in MCP that impairs regulation of C4b. These findings constitute, to our knowledge, the first genetic defects associated with preeclampsia in SLE and/or APL Ab. We confirmed the association of hypomorphic variants of MCP and CFI in a cohort of non-autoimmune preeclampsia patients in which five of 59 were heterozygous for mutations.The presence of risk variants in complement regulatory proteins in patients with SLE and/or APL Ab who develop preeclampsia, as well as in preeclampsia patients lacking autoimmune disease, links complement activation to disease pathogenesis and suggests new targets for treatment of this important public health problem.ClinicalTrials.gov NCT00198068.

  1. The Avalanche Hypothesis and Compression of Morbidity: Testing Assumptions through Cohort-Sequential Analysis.

    Directory of Open Access Journals (Sweden)

    Jordan Silberman

    Full Text Available The compression of morbidity model posits a breakpoint in the adult lifespan that separates an initial period of relative health from a subsequent period of ever increasing morbidity. Researchers often assume that such a breakpoint exists; however, this assumption is hitherto untested.To test the assumption that a breakpoint exists--which we term a morbidity tipping point--separating a period of relative health from a subsequent deterioration in health status. An analogous tipping point for healthcare costs was also investigated.Four years of adults' (N = 55,550 morbidity and costs data were retrospectively analyzed. Data were collected in Pittsburgh, PA between 2006 and 2009; analyses were performed in Rochester, NY and Ann Arbor, MI in 2012 and 2013. Cohort-sequential and hockey stick regression models were used to characterize long-term trajectories and tipping points, respectively, for both morbidity and costs.Morbidity increased exponentially with age (P<.001. A morbidity tipping point was observed at age 45.5 (95% CI, 41.3-49.7. An exponential trajectory was also observed for costs (P<.001, with a costs tipping point occurring at age 39.5 (95% CI, 32.4-46.6. Following their respective tipping points, both morbidity and costs increased substantially (Ps<.001.Findings support the existence of a morbidity tipping point, confirming an important but untested assumption. This tipping point, however, may occur earlier in the lifespan than is widely assumed. An "avalanche of morbidity" occurred after the morbidity tipping point-an ever increasing rate of morbidity progression. For costs, an analogous tipping point and "avalanche" were observed. The time point at which costs began to increase substantially occurred approximately 6 years before health status began to deteriorate.

  2. Maternal obesity, caesarean delivery and caesarean delivery on maternal request: a cohort analysis from China.

    Science.gov (United States)

    Zhou, Yubo; Blustein, Jan; Li, Hongtian; Ye, Rongwei; Zhu, Liping; Liu, Jianmeng

    2015-05-01

    To quantify the association between maternal obesity and caesarean delivery, particularly caesarean delivery on maternal request (CDMR), a fast-growing component of caesarean delivery in many nations. We followed 1,019,576 nulliparous women registered in the Perinatal Healthcare Surveillance System during 1993-2010. Maternal body mass index (BMI, kg/m(2) ), before pregnancy or during early pregnancy, was classified as underweight (obese (≥27.5), consistent with World Health Organization guidelines for Asian people. The association between maternal obesity and overall caesarean and its subtypes was modelled using log-binomial regression. During the 18-year period, 404,971 (39.7%) caesareans and 93,927 (9.2%) CDMRs were identified. Maternal obesity was positively associated with overall caesarean and CDMR. Adjusted risk ratios for overall caesarean in the four ascending BMI categories were 0.96 [95% confidence interval (CI) 0.94, 0.97], 1.00 (Reference), 1.16 [95% CI 1.14, 1.18], 1.39 [95% CI 1.43, 1.54], and for CDMR were 0.95 [95% CI 0.94, 0.96], 1.00 (Reference), 1.20 [95% CI 1.18, 1.22], 1.48 [95% CI 1.433, 1.54]. Positive associations were consistently found in women residing in southern and northern provinces and in subgroups stratified by year of delivery, urban or rural residence, maternal age, education, level of delivering hospital, and birthweight. In a large Chinese cohort study, maternal obesity was associated with an increased risk of caesarean delivery and its subtypes, including CDMR. Given the rising global prevalence of obesity, and in view of the growth of CDMR, it seems likely that caesarean births will increase, unless there are changes in obstetrical practice. © 2015 John Wiley & Sons Ltd.

  3. Ovarian Cancer Risk Factors by Histologic Subtype: An Analysis From the Ovarian Cancer Cohort Consortium.

    Science.gov (United States)

    Wentzensen, Nicolas; Poole, Elizabeth M; Trabert, Britton; White, Emily; Arslan, Alan A; Patel, Alpa V; Setiawan, V Wendy; Visvanathan, Kala; Weiderpass, Elisabete; Adami, Hans-Olov; Black, Amanda; Bernstein, Leslie; Brinton, Louise A; Buring, Julie; Butler, Lesley M; Chamosa, Saioa; Clendenen, Tess V; Dossus, Laure; Fortner, Renee; Gapstur, Susan M; Gaudet, Mia M; Gram, Inger T; Hartge, Patricia; Hoffman-Bolton, Judith; Idahl, Annika; Jones, Michael; Kaaks, Rudolf; Kirsh, Victoria; Koh, Woon-Puay; Lacey, James V; Lee, I-Min; Lundin, Eva; Merritt, Melissa A; Onland-Moret, N Charlotte; Peters, Ulrike; Poynter, Jenny N; Rinaldi, Sabina; Robien, Kim; Rohan, Thomas; Sandler, Dale P; Schairer, Catherine; Schouten, Leo J; Sjöholm, Louise K; Sieri, Sabina; Swerdlow, Anthony; Tjonneland, Anna; Travis, Ruth; Trichopoulou, Antonia; van den Brandt, Piet A; Wilkens, Lynne; Wolk, Alicja; Yang, Hannah P; Zeleniuch-Jacquotte, Anne; Tworoger, Shelley S

    2016-08-20

    An understanding of the etiologic heterogeneity of ovarian cancer is important for improving prevention, early detection, and therapeutic approaches. We evaluated 14 hormonal, reproductive, and lifestyle factors by histologic subtype in the Ovarian Cancer Cohort Consortium (OC3). Among 1.3 million women from 21 studies, 5,584 invasive epithelial ovarian cancers were identified (3,378 serous, 606 endometrioid, 331 mucinous, 269 clear cell, 1,000 other). By using competing-risks Cox proportional hazards regression stratified by study and birth year and adjusted for age, parity, and oral contraceptive use, we assessed associations for all invasive cancers by histology. Heterogeneity was evaluated by likelihood ratio test. Most risk factors exhibited significant heterogeneity by histology. Higher parity was most strongly associated with endometrioid (relative risk [RR] per birth, 0.78; 95% CI, 0.74 to 0.83) and clear cell (RR, 0.68; 95% CI, 0.61 to 0.76) carcinomas (P value for heterogeneity [P-het] < .001). Similarly, age at menopause, endometriosis, and tubal ligation were only associated with endometrioid and clear cell tumors (P-het ≤ .01). Family history of breast cancer (P-het = .008) had modest heterogeneity. Smoking was associated with an increased risk of mucinous (RR per 20 pack-years, 1.26; 95% CI, 1.08 to 1.46) but a decreased risk of clear cell (RR, 0.72; 95% CI, 0.55 to 0.94) tumors (P-het = .004). Unsupervised clustering by risk factors separated endometrioid, clear cell, and low-grade serous carcinomas from high-grade serous and mucinous carcinomas. The heterogeneous associations of risk factors with ovarian cancer subtypes emphasize the importance of conducting etiologic studies by ovarian cancer subtypes. Most established risk factors were more strongly associated with nonserous carcinomas, which demonstrate challenges for risk prediction of serous cancers, the most fatal subtype. © 2016 by American Society of Clinical Oncology.

  4. Adolescent Internet Use, Social Integration, and Depressive Symptoms: Analysis from a Longitudinal Cohort Survey.

    Science.gov (United States)

    Strong, Carol; Lee, Chih-Ting; Chao, Lo-Hsin; Lin, Chung-Ying; Tsai, Meng-Che

    2018-05-01

    To examine the association between adolescent leisure-time Internet use and social integration in the school context and how this association affects later depressive symptoms among adolescents in Taiwan, using a large nationwide cohort study and the latent growth model (LGM) method. Data of 3795 students followed from the year 2001 to 2006 in the Taiwan Education Panel Survey were analyzed. Leisure-time Internet use was defined by the hours per week spent on (1) online chatting and (2) online games. School social integration and depressive symptoms were self-reported. We first used an unconditional LGM to estimate the baseline (intercept) and growth (slope) of Internet use. Next, another LGM conditioned with school social integration and depression was conducted. Approximately 10% of the participants reported engaging in online chatting and/or gaming for more than 20 hours per week. Internet use for online chatting showed an increase over time. School social integration was associated with the baseline amount (coefficient = -0.62, p < 0.001) but not the growth of leisure-time Internet use. The trend of Internet use was positively related to depressive symptoms (coefficient = 0.31, p < 0.05) at Wave 4. School social integration was initially associated with decreased leisure-time Internet use among adolescents. The growth of Internet use with time was not explainable by school social integration but had adverse impacts on depression. Reinforcing adolescents' bonding to school may prevent initial leisure-time Internet use. When advising on adolescent Internet use, health care providers should consider their patients' social networks and mental well-being.

  5. Green space and cognitive ageing: A retrospective life course analysis in the Lothian Birth Cohort 1936.

    Science.gov (United States)

    Cherrie, Mark P C; Shortt, Niamh K; Mitchell, Richard J; Taylor, Adele M; Redmond, Paul; Thompson, Catharine Ward; Starr, John M; Deary, Ian J; Pearce, Jamie R

    2018-01-01

    International evidence suggests that green space has beneficial effects on general and mental health but little is known about how lifetime exposure to green space influences cognitive ageing. Employing a novel longitudinal life course approach, we examined the association between lifetime availability of public parks and cognitive ageing. Lifetime residential information was gathered from the participants of the Lothian Birth Cohort 1936 using a "life-grid" questionnaire at age 78 years. Parks information from 1949, 1969 and 2009 was used to determine a percentage of parks within a 1500 m buffer zone surrounding residence for childhood, adulthood, and later adulthood periods. Linear regressions were undertaken to test for association with age-standardised, residualised change in cognitive function (Moray House Test score) from age 11 to 70 years, and from age 70 to 76 (n = 281). The most appropriate model was selected using the results of a partial F-test, and then stratified by demographic, genetic and socioeconomic factors. The local provision of park space in childhood and adulthood were both important in explaining the change in cognitive function in later life. The association between childhood and adulthood park availability and change in the Moray House Test Score from age 70 to 76 was strongest for women, those without an APOE e4 allele (a genetic risk factor), and those in the lowest socioeconomic groups. Greater neighbourhood provision of public parks from childhood through to adulthood may help to slow down the rate of cognitive decline in later life, recognising that such environmental associations are always sensitive to individual characteristics. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. A multiple regression analysis for accurate background subtraction in 99Tcm-DTPA renography

    International Nuclear Information System (INIS)

    Middleton, G.W.; Thomson, W.H.; Davies, I.H.; Morgan, A.

    1989-01-01

    A technique for accurate background subtraction in 99 Tc m -DTPA renography is described. The technique is based on a multiple regression analysis of the renal curves and separate heart and soft tissue curves which together represent background activity. It is compared, in over 100 renograms, with a previously described linear regression technique. Results show that the method provides accurate background subtraction, even in very poorly functioning kidneys, thus enabling relative renal filtration and excretion to be accurately estimated. (author)

  7. Error Analysis and Calibration Method of a Multiple Field-of-View Navigation System

    OpenAIRE

    Shi, Shuai; Zhao, Kaichun; You, Zheng; Ouyang, Chenguang; Cao, Yongkui; Wang, Zhenzhou

    2017-01-01

    The Multiple Field-of-view Navigation System (MFNS) is a spacecraft subsystem built to realize the autonomous navigation of the Spacecraft Inside Tiangong Space Station. This paper introduces the basics of the MFNS, including its architecture, mathematical model and analysis, and numerical simulation of system errors. According to the performance requirement of the MFNS, the calibration of both intrinsic and extrinsic parameters of the system is assumed to be essential and pivotal. Hence, a n...

  8. MULTIPLE LINEAR REGRESSION ANALYSIS FOR PREDICTION OF BOILER LOSSES AND BOILER EFFICIENCY

    OpenAIRE

    Chayalakshmi C.L

    2018-01-01

    MULTIPLE LINEAR REGRESSION ANALYSIS FOR PREDICTION OF BOILER LOSSES AND BOILER EFFICIENCY ABSTRACT Calculation of boiler efficiency is essential if its parameters need to be controlled for either maintaining or enhancing its efficiency. But determination of boiler efficiency using conventional method is time consuming and very expensive. Hence, it is not recommended to find boiler efficiency frequently. The work presented in this paper deals with establishing the statistical mo...

  9. Effects of Radiotherapy in the treatment of multiple myeloma: a retrospective analysis of a Single Institution

    International Nuclear Information System (INIS)

    Matuschek, Christiane; Ochtrop, Thomas A; Bölke, Edwin; Ganswindt, Ute; Fenk, Roland; Gripp, Stephan; Kröpil, Patric; Gerber, Peter Arne; Kammers, Kai; Hamilton, Jackson; Orth, Klaus; Budach, Wilfried

    2015-01-01

    Palliative irradiation of osteolytic lesions is a considerable component in the treatment for patients with multiple myeloma. In this study, we analyzed the efficacy of irradiation in these patients. We retrospectively analyzed 153 patients with multiple myeloma who were admitted to our department between 1989 and 2013. According to the staging system of Durie & Salmon 116 patients were classified as stage III. 107/153 patients were treated with radiotherapy of at least one and up to 6 bony lesions at different times. In order to evaluate the effect of local radiotherapy on pain relief and bone recalcification a uni- and multivariate analysis was performed using a binary logistic regression model to correct for multiple measurements. Complete information on dose, fractionation and volume of radiotherapy was available from 81 patients treated in 136 target volumes for pain relief, and from 69 patients treated in 108 target volumes for recalcification. Total radiation doses varied between 8 Gy to 50 Gy (median dose 25 Gy in 2.5 Gy fractions, 5 times a week). Radiotherapy resulted in complete local pain relief in 31% and partial local pain relief in 54% of the patients. In the univariate analysis, higher total radiation doses (p = 0.023) and higher age (p = 0.014) at the time of radiotherapy were significantly associated with a higher likelihood of pain relief, whereas no significant association was detected for concurrent systemic treatment, type and stage of myeloma and location of bone lesions. The same variables were independent predictors for pain relief in the multivariate analysis. Recalcification was observed in 48% of irradiated bone lesions. In the uni- and multivariate analysis higher radiation doses were significantly associated (p = 0.048) with an increased likelihood of recalcification. Side effects of radiotherapy were generally mild. Higher total biological radiation doses were associated with better pain relief and recalcification in this

  10. Causal relationship between obesity and vitamin D status: bi-directional Mendelian randomization analysis of multiple cohorts

    NARCIS (Netherlands)

    Vimaleswaran, K.S.; Berry, D.J.; Lu, C.; Tikkanen, E.; Pilz, S.; Hiraki, L.T.; Cooper, J.D.; Dastani, Z.; Li, R.; Houston, D.K.; Wood, A.R.; Michaelsson, K.; Vandenput, L.; Zgaga, L.; Yerges-Armstrong, L.M.; McCarthy, M.I.; Dupuis, J.; Kaakinen, M.; Kleber, M.E.; Jameson, K.; Arden, N.; Raitakari, O.; Viikari, J.; Lohman, K.K.; Ferrucci, L.; Melhus, H.; Ingelsson, E.; Byberg, L.; Lind, L.; Lorentzon, M.; Salomaa, V.; Campbell, H.; Dunlop, M.; Mitchell, B.D.; Herzig, K.H.; Pouta, A.; Hartikainen, A.L.; Streeten, E.A.; Theodoratou, E.; Jula, A.; Wareham, N.J.; Ohlsson, C.; Frayling, T.M.; Kritchevsky, S.B.; Spector, T.D.; Richards, J.B.; Lehtimaki, T.; Ouwehand, W.H.; Kraft, P.; Cooper, C.; Marz, W.; Power, C.; Loos, R.J.; Wang, T.J.; Jarvelin, M.R.; Whittaker, J.C.; Hingorani, A.D.; Hypponen, E.; Kiemeney, L.A.L.M.; et al.,

    2013-01-01

    BACKGROUND: Obesity is associated with vitamin D deficiency, and both are areas of active public health concern. We explored the causality and direction of the relationship between body mass index (BMI) and 25-hydroxyvitamin D [25(OH)D] using genetic markers as instrumental variables (IVs) in

  11. Causal relationship between obesity and vitamin D status: bi-directional Mendelian randomization analysis of multiple cohorts

    NARCIS (Netherlands)

    Vimaleswaran, K.S.; Berry, D.J.; Lu, C.; Tikkanen, E.; Pilz, S.; Hiraki, L.T.; Cooper, J.D.; Dastani, Z.; Li, R.; Houston, D.K.; Wood, A.R.; Michaëlsson, K.; Vandenput, L.; Zgaga, L.; Yerges-Armstrong, L.M.; McCarthy, M.I.; Dupuis, J.; Kaakinen, M.; Kleber, M.E.; Jameson, K.; Arden, N.; Raitakari, O.; Viikari, J.; Lohman, K.K.; Ferrucci, L.; Melhus, H.; Ingelsson, E.; Byberg, L.; Lind, L.; Lorentzon, M.; Salomaa, V.; Campbell, H.; Dunlop, M.; Mitchell, B.D.; Herzig, K.H.; Pouta, A.; Hartikainen, A.L.; Hottenga, J.J.; de Geus, E.J.C.; Willemsen, G.; Boomsma, D.I.; Penninx, B.W.J.H.; Uitterlinden, A.G.; Visscher, P.M.; van Duijn, C.M.; Streeten, E.A.; Theodoratou, E.; Jula, A.; Wareham, N.J.; Ohlsson, C.; Frayling, T.M.; Kritchevsky, S.B.; Spector, T.D.; Richards, J.B.; Lehtimäki, T.; Ouwehand, W.H.; Kraft, P.; Cooper, C.; März, W.; Power, C.; Loos, R.J.; Wang, T.J.; Järvelin, M.R.; Whittaker, J.C.; Hingorani, A.D.; Hyppönen, E.

    2013-01-01

    Background: Obesity is associated with vitamin D deficiency, and both are areas of active public health concern. We explored the causality and direction of the relationship between body mass index (BMI) and 25-hydroxyvitamin D [25(OH)D] using genetic markers as instrumental variables (IVs) in

  12. Trends in oral cavity, pharyngeal, oesophageal and gastric cancer mortality rates in Spain, 1952-2006: an age-period-cohort analysis.

    Science.gov (United States)

    Seoane-Mato, Daniel; Aragonés, Nuria; Ferreras, Eva; García-Pérez, Javier; Cervantes-Amat, Marta; Fernández-Navarro, Pablo; Pastor-Barriuso, Roberto; López-Abente, Gonzalo

    2014-04-11

    Although oral cavity, pharyngeal, oesophageal and gastric cancers share some risk factors, no comparative analysis of mortality rate trends in these illnesses has been undertaken in Spain. This study aimed to evaluate the independent effects of age, death period and birth cohort on the mortality rates of these tumours. Specific and age-adjusted mortality rates by tumour and sex were analysed. Age-period-cohort log-linear models were fitted separately for each tumour and sex, and segmented regression models were used to detect changes in period- and cohort-effect curvatures. Among men, the period-effect curvatures for oral cavity/pharyngeal and oesophageal cancers displayed a mortality trend that rose until 1995 and then declined. Among women, oral cavity/pharyngeal cancer mortality increased throughout the study period whereas oesophageal cancer mortality decreased after 1970. Stomach cancer mortality decreased in both sexes from 1965 onwards. Lastly, the cohort-effect curvature showed a certain degree of similarity for all three tumours in both sexes, which was greater among oral cavity, pharyngeal and oesophageal cancers, with a change point in evidence, after which risk of death increased in cohorts born from the 1910-1920s onwards and decreased among the 1950-1960 cohorts and successive generations. This latter feature was likewise observed for stomach cancer. While the similarities of the cohort effects in oral cavity/pharyngeal, oesophageal and gastric tumours support the implication of shared risk factors, the more marked changes in cohort-effect curvature for oral cavity/pharyngeal and oesophageal cancer could be due to the greater influence of some risk factors in their aetiology, such as smoking and alcohol consumption. The increase in oral cavity/pharyngeal cancer mortality in women deserves further study.

  13. Antidepressant use during pregnancy and the risk of major congenital malformations in a cohort of depressed pregnant women: an updated analysis of the Quebec Pregnancy Cohort.

    Science.gov (United States)

    Bérard, Anick; Zhao, Jin-Ping; Sheehy, Odile

    2017-01-12

    Antidepressant use during gestation has been associated with risk of major congenital malformations but estimates can lack statistical power or be confounded by maternal depression. We aimed to determine the association between first-trimester exposure to antidepressants and the risk of major congenital malformations in a cohort of depressed/anxious women. Data were obtained from the Quebec Pregnancy Cohort (QPC). All pregnancies with a diagnosis of depression or anxiety, or exposed to antidepressants in the 12 months before pregnancy, and ending with a live-born singleton were included. Antidepressant classes (selective serotonin reuptake inhibitors (SSRI), serotonin-norepinephrine reuptake inhibitors (SNRI), tricyclic antidepressants (TCA) and other antidepressants) and types were individually compared with non-exposure during the first trimester (depressed untreated). Major congenital malformations overall and organ-specific malformations in the first year of life were identified. 18 487 pregnant women were included. When looking at the specific types of antidepressant used during the first trimester, only citalopram was increasing the risk of major congenital malformations (adjusted OR, (aOR) 1.36, 95% CI 1.08 to 1.73; 88 exposed cases), although there was a trend towards increased risk for the most frequently used antidepressants. Antidepressants with serotonin reuptake inhibition effect (SSRI, SNRI, amitriptyline (the most used TCA)) increased the risk of certain organ-specific defects: paroxetine increased the risk of cardiac defects (aOR 1.45, 95% CI 1.12 to 1.88), and ventricular/atrial septal defects (aOR 1.39, 95% CI 1.00 to 1.93); citalopram increased the risk of musculoskeletal defects (aOR 1.92, 95% CI 1.40 to 2.62), and craniosynostosis (aOR 3.95, 95% CI 2.08 to 7.52); TCA was associated with eye, ear, face and neck defects (aOR 2.45, 95% CI 1.05 to 5.72), and digestive defects (aOR 2.55, 95% CI 1.40 to 4.66); and venlafaxine was associated with

  14. JIGSAW: Acquisition, Display and Analysis system designed to collect data from Multiple Gamma-Ray detectors

    International Nuclear Information System (INIS)

    Ha