Designing Reliable Cohorts of Cardiac Patients across MIMIC and eICU

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Chronaki, Catherine; Shahin, Abdullah; Mark, Roger

2016-01-01

The design of the patient cohort is an essential and fundamental part of any clinical patient study. Knowledge of the Electronic Health Records, underlying Database Management System, and the relevant clinical workflows are central to an effective cohort design. However, with technical, semantic, and organizational interoperability limitations, the database queries associated with a patient cohort may need to be reconfigured in every participating site. i2b2 and SHRINE advance the notion of patient cohorts as first class objects to be shared, aggregated, and recruited for research purposes across clinical sites. This paper reports on initial efforts to assess the integration of Medical Information Mart for Intensive Care (MIMIC) and Philips eICU, two large-scale anonymized intensive care unit (ICU) databases, using standard terminologies, i.e. LOINC, ICD9-CM and SNOMED-CT. Focus of this work is lab and microbiology observations and key demographics for patients with a primary cardiovascular ICD9-CM diagnosis. Results and discussion reflecting on reference core terminology standards, offer insights on efforts to combine detailed intensive care data from multiple ICUs worldwide. PMID:27774488

The Scandinavian baltic pancreatic club (SBPC) database: design, rationale and characterisation of the study cohort.

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Olesen, Søren S; Poulsen, Jakob L; Drewes, Asbjørn M; Frøkjær, Jens B; Laukkarinen, Johanna; Parhiala, Mikael; Rix, Iben; Novovic, Srdan; Lindkvist, Björn; Bexander, Louise; Dimcevski, Georg; Engjom, Trond; Erchinger, Friedemann; Haldorsen, Ingfrid S; Pukitis, Aldis; Ozola-Zālīte, Imanta; Haas, Stephan; Vujasinovic, Miroslav; Löhr, J Matthias; Gulbinas, Antanas; Jensen, Nanna M; Jørgensen, Maiken T; Nøjgaard, Camilla

2017-08-01

Chronic pancreatitis (CP) is a multifaceted disease associated with several risk factors and a complex clinical presentation. We established the Scandinavian Baltic Pancreatic Club (SBPC) Database to characterise and study the natural history of CP in a Northern European cohort. Here, we describe the design of the database and characteristics of the study cohort. Nine centres from six different countries in the Scandinavian-Baltic region joined the database. Patients with definitive or probable CP (M-ANNHEIM diagnostic criteria) were included. Standardised case report forms were used to collect several assessment variables including disease aetiology, duration of CP, preceding acute pancreatitis, as well as symptoms, complications, and treatments. The clinical stage of CP was characterised according to M-ANNNHEIM. Yearly follow-up is planned for all patients. The study cohort comprised of 910 patients (608 men: 302 women; median age 58 (IQR: 48-67) years with definite 848 (93%) or probable CP 62 (7%). Nicotine (70%) and alcohol (59%) were the most frequent aetiologies and seen in combination in 44% of patients. A history of recurrent acute pancreatitis was seen in 49% prior to the development of CP. Pain (69%) and exocrine pancreatic insufficiency (68%) were the most common complications followed by diabetes (43%). Most patients (30%) were classified as clinical stage II (symptomatic CP with exocrine or endocrine insufficiency). Less than 10% of the patients had undergone pancreatic surgery. The SBPC database provides a mean for future prospective, observational studies of CP in the Northern European continent.

Recruiting black Americans in a large cohort study: the Adventist Health Study-2 (AHS-2) design, methods and participant characteristics.

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Herring, R Patti; Butler, Terry; Hall, Sonja; Montgomery, Susanne B; Fraser, Gary E

2010-01-01

The goal of the prospective Adventist Health Study-2 (AHS-2) was to examine the relationship between diet and risk of breast, prostate and colon cancers in Black and White participants. This paper describes the study design, recruitment methods, response rates, and characteristics of Blacks in the AHS-2, thus providing insights about effective strategies to recruit Blacks to participate in research studies. We designed a church-based recruitment model and trained local recruiters who used various strategies to recruit participants in their churches. Participants completed a 50-page self-administered dietary and lifestyle questionnaire. Participants are Black Seventh-day Adventists, aged 30-109 years, and members of 1,209 Black churches throughout the United States and Canada. Approximately 48,328 Blacks from an estimated target group of over 90,000 signed up for the study and 25,087 completed the questionnaire, comprising about 26% of the larger 97,000 AHS-2-member cohort. Participants were diverse in age, geographic location, education, and income. Seventy percent were female with a median age of 59 years. In spite of many recruitment challenges and barriers, we successfully recruited a large cohort whose data should provide some answers as to why Blacks have poorer health outcomes than several other ethnic groups, and help explain existing health disparities.

Study design of DIACORE (DIAbetes COhoRtE – a cohort study of patients with diabetes mellitus type 2

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Dörhöfer Lena

2013-02-01

Full Text Available Abstract Background Diabetes mellitus type 2 (DM2 is highly associated with increased risk for chronic kidney disease (CKD, end stage renal disease (ESRD and cardiovascular morbidity. Epidemiological and genetic studies generate hypotheses for innovative strategies in DM2 management by unravelling novel mechanisms of diabetes complications, which is essential for future intervention trials. We have thus initiated the DIAbetes COhoRtE study (DIACORE. Methods DIACORE is a prospective cohort study aiming to recruit 6000 patients of self-reported Caucasian ethnicity with prevalent DM2 for at least 10 years of follow-up. Study visits are performed in University-based recruiting clinics in Germany using standard operating procedures. All prevalent DM2 patients in outpatient clinics surrounding the recruiting centers are invited to participate. At baseline and at each 2-year follow-up examination, patients are subjected to a core phenotyping protocol. This includes a standardized online questionnaire and physical examination to determine incident micro- and macrovascular DM2 complications, malignancy and hospitalization, with a primary focus on renal events. Confirmatory outcome information is requested from patient records. Blood samples are obtained for a centrally analyzed standard laboratory panel and for biobanking of aliquots of serum, plasma, urine, mRNA and DNA for future scientific use. A subset of the cohort is subjected to extended phenotyping, e.g. sleep apnea screening, skin autofluorescence measurement, non-mydriatic retinal photography and non-invasive determination of arterial stiffness. Discussion DIACORE will enable the prospective evaluation of factors involved in DM2 complication pathogenesis using high-throughput technologies in biosamples and genetic epidemiological studies.

The Nightingale study: rationale, study design and baseline characteristics of a prospective cohort study on shift work and breast cancer risk among nurses.

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Pijpe, Anouk; Slottje, Pauline; van Pelt, Cres; Stehmann, Floor; Kromhout, Hans; van Leeuwen, Flora E; Vermeulen, Roel C H; Rookus, Matti A

2014-01-29

Evidence for the carcinogenicity of shift work in humans is limited because of significant heterogeneity of the results, thus more in-depth research in needed. The Nightingale Study is a nationwide prospective cohort study on occupational exposures and risks of chronic diseases among female nurses and focuses on the potential association between shift work and risk of breast cancer. The study design, methods, and baseline characteristics of the cohort are described. The source population for the cohort comprised 18 to 65 year old women who were registered as having completed training to be a nurse in the nationwide register for healthcare professionals in the Netherlands. Eligible women were invited to complete a web-based questionnaire including full job history, a detailed section on all domains of shift work (shift system, cumulative exposure, and shift intensity) and potential confounding factors, and an informed consent form for linkage with national (disease) registries. Women were also asked to donate toenail clippings as a source of DNA for genetic analyses. Between October 6, 2011 and February 1, 2012, 31% of the 192,931 women who were invited to participate completed the questionnaire, yielding a sample size of 59,947 cohort members. The mean age of the participants was 46.9 year (standard deviation 11.0 years). Toenail clippings were provided by 23,439 participants (39%). Results from the Nightingale Study will contribute to the scientific evidence of potential shift work-related health risks among nurses and will help develop preventive measures and policy aimed at reducing these risks.

The Norwegian Offender Mental Health and Addiction Study – Design and Implementation of a National Survey and Prospective Cohort Study

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Anne Bukten

2015-01-01

Full Text Available The Norwegian prison inmates are burdened by problems before they enter prison. Few studies have managed to assess this burden and relate it to what occurs for the inmates once they leave the prison. The Norwegian Offender Mental Health and Addiction (NorMA study is a large-scale longitudinal cohort study that combines national survey and registry data in order to understand mental health, substance use, and criminal activity before, during, and after custody among prisoners in Norway. The main goal of the study is to describe the criminal and health-related trajectories based on both survey and registry linkage information. Data were collected from 1,499 inmates in Norwegian prison facilities during 2013–2014. Of these, 741 inmates provided a valid personal identification number and constitute a cohort that will be examined retrospectively and prospectively, along with data from nationwide Norwegian registries. This study describes the design, procedures, and implementation of the ongoing NorMA study and provides an outline of the initial data.

Cohort profile: the Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS), a multicentre cohort for socioeconomic inequalities in health monitoring.

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Caranci, Nicola; Di Girolamo, Chiara; Giorgi Rossi, Paolo; Spadea, Teresa; Pacelli, Barbara; Broccoli, Serena; Ballotari, Paola; Costa, Giuseppe; Zengarini, Nicolás; Agabiti, Nera; Bargagli, Anna Maria; Cacciani, Laura; Canova, Cristina; Cestari, Laura; Biggeri, Annibale; Grisotto, Laura; Terni, Gianna; Costanzo, Gianfranco; Mirisola, Concetta; Petrelli, Alessio

2018-04-20

The Italian Network of Longitudinal Metropolitan Studies (IN-LiMeS) is a system of integrated data on health outcomes, demographic and socioeconomic information, and represents a powerful tool to study health inequalities. IN-LiMeS is a multicentre and multipurpose pool of metropolitan population cohorts enrolled in nine Italian cities: Turin, Venice, Reggio Emilia, Modena, Bologna, Florence, Leghorn, Prato and Rome. Data come from record linkage of municipal population registries, the 2001 population census, mortality registers and hospital discharge archives. Depending on the source of enrolment, cohorts can be closed or open. The census-based closed cohort design includes subjects resident in any of the nine cities at the 2001 census day; 4 466 655 individuals were enrolled in 2001 in the nine closed cohorts. The open cohort design includes subjects resident in 2001 or subsequently registered by birth or immigration until the latest available follow-up (currently 31 December 2013). The open cohort design is available for Turin, Venice, Reggio Emilia, Modena, Bologna, Prato and Rome. Detailed socioeconomic data are available for subjects enrolled in the census-based cohorts; information on demographic characteristics, education and citizenship is available from population registries. The first IN-LiMeS application was the study of differentials in mortality between immigrants and Italians. Either using a closed cohort design (nine cities) or an open one (Turin and Reggio Emilia), individuals from high migration pressure countries generally showed a lower mortality risk. However, a certain heterogeneity between the nine cities was noted, especially among men, and an excess mortality risk was reported for some macroareas of origin and specific causes of death. We are currently working on the linkage of the 2011 population census data, the expansion of geographical coverage and the implementation of the open design in all the participating cohorts. © Article author

Japan Diabetic Nephropathy Cohort Study: study design, methods, and implementation.

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Furuichi, Kengo; Shimizu, Miho; Toyama, Tadashi; Koya, Daisuke; Koshino, Yoshitaka; Abe, Hideharu; Mori, Kiyoshi; Satoh, Hiroaki; Imanishi, Masahito; Iwano, Masayuki; Yamauchi, Hiroyuki; Kusano, Eiji; Fujimoto, Shouichi; Suzuki, Yoshiki; Okuda, Seiya; Kitagawa, Kiyoki; Iwata, Yasunori; Kaneko, Shuichi; Nishi, Shinichi; Yokoyama, Hitoshi; Ueda, Yoshihiko; Haneda, Masakazu; Makino, Hirofumi; Wada, Takashi

2013-12-01

Diabetic nephropathy, leading to end-stage renal disease, has a considerable impact on public health and the social economy. However, there are few national registries of diabetic nephropathy in Japan. The aims of this prospective cohort study are to obtain clinical data and urine samples for revising the clinical staging of diabetic nephropathy, and developing new diagnostic markers for early diabetic nephropathy. The Japanese Society of Nephrology established a nationwide, web-based, and prospective registry system. On the system, there are two basic registries; the Japan Renal Biopsy Registry (JRBR), and the Japan Kidney Disease Registry (JKDR). In addition to the two basic registries, we established a new prospective registry to the system; the Japan Diabetic Nephropathy Cohort Study (JDNCS), which collected physical and laboratory data. We analyzed the data of 321 participants (106 female, 215 male; average age 65 years) in the JDNCS. Systolic and diastolic blood pressure was 130.1 and 72.3 mmHg, respectively. Median estimated glomerular filtration rate (eGFR) was 33.3 ml/min/1.73 m(2). Proteinuria was 1.8 g/gCr, and serum levels of albumin were 3.6 g/dl. The majority of the JDNCS patients presented with preserved eGFR and low albuminuria or low eGFR and advanced proteinuria. In the JRBR and JKDR registries, 484 and 125 participants, respectively, were enrolled as having diabetes mellitus. In comparison with the JRBR and JKDR registries, the JDNCS was characterized by diabetic patients presenting with low proteinuria with moderately preserved eGFR. There are few national registries of diabetic nephropathy to evaluate prognosis in Japan. Future analysis of the JDNCS will provide clinical insights into the epidemiology and renal and cardiovascular outcomes of type 2 diabetic patients in Japan.

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...

The Shozu Herpes Zoster (SHEZ) Study: Rationale, Design, and Description of a Prospective Cohort Study

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Takao, Yukiko; Miyazaki, Yoshiyuki; Onishi, Fumitake; Kumihashi, Hideaki; Gomi, Yasuyuki; Ishikawa, Toyokazu; Okuno, Yoshinobu; Mori, Yasuko; Asada, Hideo; Yamanishi, Koichi; Iso, Hiroyasu

2012-01-01

Background The incidence and risk factors for herpes zoster have been studied in cross-sectional and cohort studies, although most such studies have been conducted in Western countries. Evidence from Asian populations is limited, and no cohort study has been conducted in Asia. We are conducting a 3-year prospective cohort study in Shozu County in Kagawa Prefecture, Japan to determine the incidence and predictive and immunologic factors for herpes zoster among Japanese. Methods The participants are followed for 3 years, and a telephone survey is conducted every 4 weeks. The participants were assigned to 1 of 3 studies. Participants in study A gave information on past history of herpes zoster and completed health questionnaires. Study B participants additionally underwent varicella-zoster virus (VZV) skin testing, and study C participants additionally underwent blood testing. If the participants develop herpes zoster, we evaluate clinical symptoms, measure cell-mediated immunity and humoral immunity using venous blood sampling, photograph skin areas with rash, conduct virus identification testing by polymerase chain reaction (PCR) and virus isolation from crust sampling, and evaluate postherpetic pain. Results We recruited 12 522 participants aged 50 years or older in Shozu County from December 2009 through November 2010. The participation rate was 65.7% of the target population. Conclusions The present study is likely to provide valuable data on the incidence and predictive and immunologic factors for herpes zoster in a defined community-based population of Japanese. PMID:22343323

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

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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.

Revitalising the Metropolit 1953 Danish male birth cohort: background, aims and design

DEFF Research Database (Denmark)

Osler, Merete; Andersen, Anne-Marie Nybo; Lund, Rikke

2004-01-01

mobility. At age 12 years, 9537 of these cohort members completed a questionnaire in school, which included cognitive measures and information on social aspirations and leisure time activities. In 1966 educational performance tests were administered for these boys and, in 1968, mothers of 2890 cohort......Recent research indicates that factors operating during childhood are related to adult health. Thus, longitudinal studies with information on subsequent phases may be key to understanding later health outcomes. The main objective of this paper is to describe the history and design of a Danish birth...... cohort, and its revitalisation. In 1965, information from birth certificates for 11 591 of a total of 12 270 males born in 1953 in the Metropolitan area of Copenhagen, Denmark were traced. These boys were the study population of a sociological investigation conducted with the aim of describing social...

A Cohort Study on Long-Term Adverse Effects of Parental Drinking: Background and Study Design

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Ingunn Olea Lund

2015-01-01

Full Text Available Although many studies have addressed adverse outcomes in children of parents with alcohol abuse/dependence, less is known about the possible long-term effects of more normative patterns of parental alcohol consumption, including drinking at lower risk levels and heavy episodic or binge drinking. The extent of harm from parental drinking may therefore be underestimated. With this research proposal, we describe a project that aims to assess possible long-term adverse effects of parental drinking by combining survey and nationwide registry data. Advantages of a longitudinal general population cohort design include that it allows for detailed information on parental drinking through survey data and identification of possible negative long-term health and social outcomes from exposure to parental drinking 1–19 years after exposure through continuously updated nationwide registers. The rich information available from combining survey and registry data allows us to take into account important confounders, mediators, and moderators.

International Network of Chronic Kidney Disease cohort studies (iNET-CKD): a global network of chronic kidney disease cohorts.

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Dienemann, Thomas; Fujii, Naohiko; Orlandi, Paula; Nessel, Lisa; Furth, Susan L; Hoy, Wendy E; Matsuo, Seiichi; Mayer, Gert; Methven, Shona; Schaefer, Franz; Schaeffner, Elke S; Solá, Laura; Stengel, Bénédicte; Wanner, Christoph; Zhang, Luxia; Levin, Adeera; Eckardt, Kai-Uwe; Feldman, Harold I

2016-09-02

Chronic kidney disease (CKD) is a global health burden, yet it is still underrepresented within public health agendas in many countries. Studies focusing on the natural history of CKD are challenging to design and conduct, because of the long time-course of disease progression, a wide variation in etiologies, and a large amount of clinical variability among individuals with CKD. With the difference in health-related behaviors, healthcare delivery, genetics, and environmental exposures, this variability is greater across countries than within one locale and may not be captured effectively in a single study. Studies were invited to join the network. Prerequisites for membership included: 1) observational designs with a priori hypotheses and defined study objectives, patient-level information, prospective data acquisition and collection of bio-samples, all focused on predialysis CKD patients; 2) target sample sizes of 1,000 patients for adult cohorts and 300 for pediatric cohorts; and 3) minimum follow-up of three years. Participating studies were surveyed regarding design, data, and biosample resources. Twelve prospective cohort studies and two registries covering 21 countries were included. Participants age ranges from >2 to >70 years at inclusion, CKD severity ranges from stage 2 to stage 5. Patient data and biosamples (not available in the registry studies) are measured yearly or biennially. Many studies included multiple ethnicities; cohort size ranges from 400 to more than 13,000 participants. Studies' areas of emphasis all include but are not limited to renal outcomes, such as progression to ESRD and death. iNET-CKD (International Network of CKD cohort studies) was established, to promote collaborative research, foster exchange of expertise, and create opportunities for research training. Participating studies have many commonalities that will facilitate comparative research; however, we also observed substantial differences. The diversity we observed across

Age, time period, and birth cohort differences in self-esteem: Reexamining a cohort-sequential longitudinal study.

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Twenge, Jean M; Carter, Nathan T; Campbell, W Keith

2017-05-01

Orth, Trzesniewski, and Robins (2010) concluded that the nationally representative Americans' Changing Lives (ACL) cohort-sequential study demonstrated moderate to large age differences in self-esteem, and no birth cohort (generational) differences in the age trajectory. In a reanalysis of these data using 2 different statistical techniques, we find significant increases in self-esteem that could be attributed to birth cohort or time period. First, hierarchical linear modeling analyses with birth cohort as a continuous variable (vs. the multiple group formulation used by Orth et al.) find that birth cohort has a measurable influence on self-esteem through its interaction with age. Participants born in later years (e.g., 1960) were higher in self-esteem and were more likely to increase in self-esteem as they aged than participants born in earlier years (e.g., 1920). However, the estimated age trajectory up to age 60 is similar in Orth et al.'s results and in the results from our analyses including cohort. Second, comparing ACL respondents of the same age in 1986 versus 2002 (a time-lag design) yields significant birth cohort differences in self-esteem, with 2002 participants of the same age higher in self-esteem than those in 1986. Combined with some previous studies finding significant increases in self-esteem and positive self-views over time, these results suggest that cultural change in the form of cohort and time period cannot be ignored as influences in cross-sectional and longitudinal studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Design and conduct of an internet-based preconception cohort study in North America: Pregnancy Study Online (PRESTO)

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Wise, Lauren A; Rothman, Kenneth J.; Mikkelsen, Ellen M.; Stanford, Joseph B.; Wesselink, Amelia K.; McKinnon, Craig; Gruschow, Siobhan M.; Horgan, Casie E.; Wiley, Aleta S.; Hahn, Kristen A.; Sørensen, Henrik Toft; Hatch, Elizabeth E.

2015-01-01

Background We launched the Boston University Pregnancy Study Online (PRESTO) to assess the feasibility of carrying out an internet-based preconception cohort study in the U.S. and Canada. Methods We recruited female participants age 21–45 and their male partners through internet advertisements, word of mouth, and flyers. Female participants were randomized with 50% probability to receive a subscription to FertilityFriend.com (FF), a web-based program that collects real-time data on menstrual characteristics. We compared recruitment methods within PRESTO, assessed the cost-efficiency of PRESTO relative to its Danish counterpart (Snart-Gravid), and validated retrospectively-reported date of last menstrual period (LMP) against FF data. Results After 99 weeks of recruitment (2013–2015), 2,421 women enrolled; 1,384 (57%) invited their male partners to participate, of whom 693 (50%) enrolled. Baseline characteristics were balanced across randomization groups. Cohort retention was similar among those randomized vs. not randomized to FF (84% vs. 81%). At study enrollment, 56%, 22%, and 22% couples had been trying to conceive for cost per subject enrolled was $146 (2013 $US), which was similar to our companion Danish study and half that of a traditional cohort study. Among FF users who conceived, >97% reported their LMP on the PRESTO questionnaire within 1 day of the LMP recorded via FF. Conclusions Use of the internet as a method of recruitment and follow-up in a North American preconception cohort study was feasible and cost-effective. PMID:26111445

Reassessment of HIV-1 acute phase infectivity: accounting for heterogeneity and study design with simulated cohorts.

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Steve E Bellan

2015-03-01

= 1.7 mo (95% CrI: 0.55-6.8. The wide credibility intervals reflect an inability to distinguish a long, mildly infectious acute phase from a short, highly infectious acute phase, given the 10-mo Rakai observation intervals. The total additional risk, measured as excess hazard-months attributable to the acute phase (EHMacute can be estimated more precisely: EHMacute = (RHacute - 1 × dacute, and should be interpreted with respect to the 120 hazard-months generated by a constant untreated chronic phase infectivity over 10 y of infection. From the Rakai data, we estimated that EHMacute = 8.4 (95% CrI: -0.27 to 64. This estimate is considerably lower than previously published estimates, and consistent with our independent estimate from viral load trajectories, 5.6 (95% confidence interval: 3.3-9.1. We found that previous overestimates likely stemmed from failure to account for risk heterogeneity and bias resulting from the retrospective cohort study design. Our results reflect the interaction between the retrospective cohort exclusion criteria and high (47% rates of censorship amongst incident serodiscordant couples in the Rakai study due to loss to follow-up, couple dissolution, or study termination. We estimated excess physiological infectivity during the acute phase from couples data, but not the proportion of transmission attributable to the acute phase, which would require data on the broader population's sexual network structure.Previous EHMacute estimates relying on the Rakai retrospective cohort data range from 31 to 141. Our results indicate that these are substantial overestimates of HIV-1 acute phase infectivity, biased by unmodeled heterogeneity in transmission rates between couples and by inconsistent censoring. Elevated acute phase infectivity is therefore less likely to undermine TasP interventions than previously thought. Heterogeneity in infectiousness and susceptibility may still play an important role in intervention success and deserves attention in

1970 British Cohort Study

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Matt Brown

2014-10-01

Full Text Available The 1970 British Cohort Study (BCS70 is one of Britain’s world famous national longitudinal birth cohort studies, three of which are run by the Centre for Longitudinal Studies at the Institute of Education, University of London.  BCS70 follows the lives of more than 17,000 people born in England, Scotland and Wales in a single week of 1970. Over the course of cohort members lives, the BCS70 has collected information on health, physical, educational and social development, and economic circumstances among other factors. Since the birth survey in 1970, there have been nine ‘sweeps’ of all cohort members at ages 5, 10, 16, 26, 30, 34, 38 and most recently at 42. Data has been collected from a number of different sources (the midwife present at birth, parents of the cohort members, head and class teachers, school health service personnel and the cohort members themselves. The data has been collected in a variety of ways including via paper and electronic questionnaires, clinical records, medical examinations, physical measurements, tests of ability, educational assessments and diaries. The majority of BCS70 survey data can be accessed by bona fide researchers through the UK Data Service at the University of Essex.

Living with diabetes: rationale, study design and baseline characteristics for an Australian prospective cohort study

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Donald Maria

2012-01-01

Full Text Available Abstract Background Diabetes mellitus is a major global public health threat. In Australia, as elsewhere, it is responsible for a sizeable portion of the overall burden of disease, and significant costs. The psychological and social impact of diabetes on individuals with the disease can be severe, and if not adequately addressed, can lead to the worsening of the overall disease picture. The Living With Diabetes Study aims to contribute to a holistic understanding of the psychological and social aspects of diabetes mellitus. Methods/Design The Living With Diabetes Study is a 5-year prospective cohort study, based in Queensland, Australia. The first wave of data, which was collected via a mailed self-report survey, was gathered in 2008, with annual collections thereafter. Measurements include: demographic, lifestyle, health and disease characteristics; quality of life (EQ-5D, ADDQoL; emotional well-being (CES-D, LOT-R, ESSI; disease self-management (PAM; and health-care utilisation and patient-assessed quality of care (PACIC. 29% of the 14,439 adults who were invited to participate in the study agreed to do so, yielding a sample size of 3,951 people. Discussion The data collected by the Living With Diabetes Study provides a good representation of Australians with diabetes to follow over time in order to better understand the natural course of the illness. The study has potential to further illuminate, and give a comprehensive picture of the psychosocial implications of living with diabetes. Data collection is ongoing.

Reassessment of HIV-1 Acute Phase Infectivity: Accounting for Heterogeneity and Study Design with Simulated Cohorts

Science.gov (United States)

Bellan, Steve E.; Dushoff, Jonathan; Galvani, Alison P.; Meyers, Lauren Ancel

2015-01-01

.79–57) and d acute = 1.7 mo (95% CrI: 0.55–6.8). The wide credibility intervals reflect an inability to distinguish a long, mildly infectious acute phase from a short, highly infectious acute phase, given the 10-mo Rakai observation intervals. The total additional risk, measured as excess hazard-months attributable to the acute phase (EHMacute) can be estimated more precisely: EHMacute = (RHacute - 1) × d acute, and should be interpreted with respect to the 120 hazard-months generated by a constant untreated chronic phase infectivity over 10 y of infection. From the Rakai data, we estimated that EHMacute = 8.4 (95% CrI: -0.27 to 64). This estimate is considerably lower than previously published estimates, and consistent with our independent estimate from viral load trajectories, 5.6 (95% confidence interval: 3.3–9.1). We found that previous overestimates likely stemmed from failure to account for risk heterogeneity and bias resulting from the retrospective cohort study design. Our results reflect the interaction between the retrospective cohort exclusion criteria and high (47%) rates of censorship amongst incident serodiscordant couples in the Rakai study due to loss to follow-up, couple dissolution, or study termination. We estimated excess physiological infectivity during the acute phase from couples data, but not the proportion of transmission attributable to the acute phase, which would require data on the broader population's sexual network structure. Conclusions Previous EHMacute estimates relying on the Rakai retrospective cohort data range from 31 to 141. Our results indicate that these are substantial overestimates of HIV-1 acute phase infectivity, biased by unmodeled heterogeneity in transmission rates between couples and by inconsistent censoring. Elevated acute phase infectivity is therefore less likely to undermine TasP interventions than previously thought. Heterogeneity in infectiousness and susceptibility may still play an important role in

The HAPPY study (Holistic Approach to Pregnancy and the first Postpartum Year): design of a large prospective cohort study.

Science.gov (United States)

Truijens, Sophie E M; Meems, Margreet; Kuppens, Simone M I; Broeren, Maarten A C; Nabbe, Karin C A M; Wijnen, Hennie A; Oei, S Guid; van Son, Maarten J M; Pop, Victor J M

2014-09-08

The HAPPY study is a large prospective longitudinal cohort study in which pregnant women (N ≈ 2,500) are followed during the entire pregnancy and the whole first year postpartum. The study collects a substantial amount of psychological and physiological data investigating all kinds of determinants that might interfere with general well-being during pregnancy and postpartum, with special attention to the effect of maternal mood, pregnancy-related somatic symptoms (including nausea and vomiting (NVP) and carpal tunnel syndrome (CTS) symptoms), thyroid function, and human chorionic gonadotropin (HCG) on pregnancy outcome of mother and foetus. During pregnancy, participants receive questionnaires at 12, 22 and 32 weeks of gestation. Apart from a previous obstetric history, demographic features, distress symptoms, and pregnancy-related somatic symptoms are assessed. Furthermore, obstetrical data of the obstetric record form and ultrasound data are collected during pregnancy. At 12 and 30 weeks, thyroid function is assessed by blood analysis of thyroid stimulating hormone (TSH), free thyroxine (FT4) and thyroid peroxidase antibodies (TPO-Ab), as well as HCG. Also, depression is assessed with special focus on the two key symptoms: depressed mood and anhedonia. After childbirth, cord blood, neonatal heel screening results and all obstetrical data with regard to start of labour, mode of delivery and complications are collected. Moreover, mothers receive questionnaires at one week, six weeks, four, eight, and twelve months postpartum, to investigate recovery after pregnancy and delivery, including postpartum mood changes, emotional distress, feeding and development of the newborn. The key strength of this large prospective cohort study is the holistic (multifactorial) approach on perinatal well-being combined with a longitudinal design with measurements during all trimesters of pregnancy and the whole first year postpartum, taking into account two physiological possible

Apparently-Different Clearance Rates from Cohort Studies of Mycoplasma genitalium Are Consistent after Accounting for Incidence of Infection, Recurrent Infection, and Study Design.

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Timo Smieszek

Full Text Available Mycoplasma genitalium is a potentially major cause of urethritis, cervicitis, pelvic inflammatory disease, infertility, and increased HIV risk. A better understanding of its natural history is crucial to informing control policy. Two extensive cohort studies (students in London, UK; Ugandan sex workers suggest very different clearance rates; we aimed to understand the reasons and obtain improved estimates by making maximal use of the data from the studies. As M. genitalium is a sexually-transmitted infectious disease, we developed a model for time-to-event analysis that incorporates the processes of (reinfection and clearance, and fitted to data from the two cohort studies to estimate incidence and clearance rates under different scenarios of sexual partnership dynamics and study design (including sample handling and associated test sensitivity. In the London students, the estimated clearance rate is 0.80 p.a. (mean duration 15 months, with incidence 1.31%-3.93% p.a. Without adjusting for study design, corresponding estimates from the Ugandan data are 3.44 p.a. (mean duration 3.5 months and 58% p.a. Apparent differences in clearance rates are probably mostly due to lower testing sensitivity in the Uganda study due to differences in sample handling, with 'true' clearance rates being similar, and adjusted incidence in Uganda being 28% p.a. Some differences are perhaps due to the sex workers having more-frequent antibiotic treatment, whilst reinfection within ongoing sexual partnerships might have caused some of the apparently-persistent infection in the London students. More information on partnership dynamics would inform more accurate estimates of natural-history parameters. Detailed studies in men are also required.

How to investigate and adjust for selection bias in cohort studies

DEFF Research Database (Denmark)

Nohr, Ellen A; Liew, Zeyan

2018-01-01

National Birth Cohort (DNBC) as examples on how to quantify selection bias and also understand the underlying selection mechanisms. Although women who chose to participate in the cohort were typically of higher social status, healthier and with less disease than all those eligible for study, differential...... of the presented methods are applicable even with limited data on non-participants and those lost to follow-up, and can also be applied to other study designs such as case-control studies and surveys. This article is protected by copyright. All rights reserved.......Longitudinal cohort studies can provide important evidence about preventable causes of disease, but the success relies heavily on the commitment of their participants, both at recruitment and during follow-up. Initial participation rates have decreased in recent decades as have willingness...

Integrative study of pandemic A/H1N1 influenza infections: design and methods of the CoPanFlu-France cohort

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Lapidus Nathanael

2012-06-01

Full Text Available Abstract Background The risk of influenza infection depends on biological characteristics, individual or collective behaviors and the environmental context. The Cohorts for Pandemic Influenza (CoPanFlu France study was set up in 2009 after the identification of the novel swine-origin A/H1N1 pandemic influenza virus. This cohort of 601 households (1450 subjects representative for the general population aims at using an integrative approach to study the risk and characteristics of influenza infection as a complex combination of data collected from questionnaires regarding sociodemographic, medical, behavioral characteristics of subjects and indoor environment, using biological samples or environmental databases. Methods/Design Households were included between December 2009 and July 2010. The design of this study relies on systematic follow-up visits between influenza seasons and additional visits during influenza seasons, when an influenza-like illness is detected in a household via an active surveillance system. During systematic visits, a nurse collects individual and environmental data on questionnaires and obtains blood samples from all members of the household. When an influenza-like-illness is detected, a nurse visits the household three times during the 12 following days, and collects data on questionnaires regarding exposure and symptoms, and biological samples (including nasal swabs from all subjects in the household. The end of the follow-up period is expected in fall 2012. Discussion The large amount of data collected throughout the follow-up will permit a multidisciplinary study of influenza infections. Additional data is being collected and analyzed in this ongoing cohort. The longitudinal analysis of these households will permit integrative analyses of complex phenomena such as individual, collective and environmental risk factors of infection, routes of transmission, or determinants of the immune response to infection or vaccination.

Study protocol: the JEU cohort study--transversal multiaxial evaluation and 5-year follow-up of a cohort of French gamblers.

Science.gov (United States)

Challet-Bouju, Gaëlle; Hardouin, Jean-Benoit; Vénisse, Jean-Luc; Romo, Lucia; Valleur, Marc; Magalon, David; Fatséas, Mélina; Chéreau-Boudet, Isabelle; Gorsane, Mohamed-Ali; Grall-Bronnec, Marie

2014-08-20

There is abundant literature on how to distinguish problem gambling (PG) from social gambling, but there are very few studies of the long-term evolution of gambling practice. As a consequence, the correlates of key state changes in the gambling trajectory are still unknown. The objective of the JEU cohort study is to identify the determinants of key state changes in the gambling practice, such as the emergence of a gambling problem, natural recovery from a gambling problem, resolution of a gambling problem with intermediate care intervention, relapses or care recourse. The present study was designed to overcome the limitations of previous cohort study on PG. Indeed, this longitudinal case-control cohort is the first which plans to recruit enough participants from different initial gambling severity levels to observe these rare changes. In particular, we plan to recruit three groups of gamblers: non-problem gamblers, problem gamblers without treatment and problem gamblers seeking treatment.Recruitment takes place in various gambling places, through the press and in care centers. Cohort participants are gamblers of both sexes who reported gambling on at least one occasion in the previous year and who were aged between 18 and 65. They were assessed through a structured clinical interview and self-assessment questionnaires at baseline and then once a year for five years. Data collection comprises sociodemographic characteristics, gambling habits (including gambling trajectory), the PG section of the DSM-IV, the South Oaks Gambling Screen, the Gambling Attitudes and Beliefs Survey - 23, the Mini International Neuropsychiatric Interview, the Wender-Utah Rating Scale-Child, the Adult ADHD Self-report Scale, somatic comorbidities (especially current treatment and Parkinson disease) and the Temperament and Character Inventory - 125. The JEU cohort study is the first study which proposes to identify the predictive factors of key state changes in gambling practice. This is

Design of an Air Pollution Monitoring Campaign in Beijing for Application to Cohort Health Studies.

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Vedal, Sverre; Han, Bin; Xu, Jia; Szpiro, Adam; Bai, Zhipeng

2017-12-15

No cohort studies in China on the health effects of long-term air pollution exposure have employed exposure estimates at the fine spatial scales desirable for cohort studies with individual-level health outcome data. Here we assess an array of modern air pollution exposure estimation approaches for assigning within-city exposure estimates in Beijing for individual pollutants and pollutant sources to individual members of a cohort. Issues considered in selecting specific monitoring data or new monitoring campaigns include: needed spatial resolution, exposure measurement error and its impact on health effect estimates, spatial alignment and compatibility with the cohort, and feasibility and expense. Sources of existing data largely include administrative monitoring data, predictions from air dispersion or chemical transport models and remote sensing (specifically satellite) data. New air monitoring campaigns include additional fixed site monitoring, snapshot monitoring, passive badge or micro-sensor saturation monitoring and mobile monitoring, as well as combinations of these. Each of these has relative advantages and disadvantages. It is concluded that a campaign in Beijing that at least includes a mobile monitoring component, when coupled with currently available spatio-temporal modeling methods, should be strongly considered. Such a campaign is economical and capable of providing the desired fine-scale spatial resolution for pollutants and sources.

Design of an Air Pollution Monitoring Campaign in Beijing for Application to Cohort Health Studies

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Sverre Vedal

2017-12-01

Full Text Available No cohort studies in China on the health effects of long-term air pollution exposure have employed exposure estimates at the fine spatial scales desirable for cohort studies with individual-level health outcome data. Here we assess an array of modern air pollution exposure estimation approaches for assigning within-city exposure estimates in Beijing for individual pollutants and pollutant sources to individual members of a cohort. Issues considered in selecting specific monitoring data or new monitoring campaigns include: needed spatial resolution, exposure measurement error and its impact on health effect estimates, spatial alignment and compatibility with the cohort, and feasibility and expense. Sources of existing data largely include administrative monitoring data, predictions from air dispersion or chemical transport models and remote sensing (specifically satellite data. New air monitoring campaigns include additional fixed site monitoring, snapshot monitoring, passive badge or micro-sensor saturation monitoring and mobile monitoring, as well as combinations of these. Each of these has relative advantages and disadvantages. It is concluded that a campaign in Beijing that at least includes a mobile monitoring component, when coupled with currently available spatio-temporal modeling methods, should be strongly considered. Such a campaign is economical and capable of providing the desired fine-scale spatial resolution for pollutants and sources.

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study.

Science.gov (United States)

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-03-07

The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1,022 ,79 Social Security members: 840,770 (82.2%) contributors and 182,009 (17.8%) beneficiaries aged 16 and older. The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of the cohort with mortality registries. Published by the BMJ

Current management and prognostic factors in physiotherapy practice for patients with shoulder pain: design of a prospective cohort study.

Science.gov (United States)

Karel, Yasmaine H J M; Scholten-Peeters, Wendy G M; Thoomes-de Graaf, Marloes; Duijn, Edwin; Ottenheijm, Ramon P G; van den Borne, Maaike P J; Koes, Bart W; Verhagen, Arianne P; Dinant, Geert-Jan; Tetteroo, Eric; Beumer, Annechien; van Broekhoven, Joost B; Heijmans, Marcel

2013-02-11

Shoulder pain is disabling and has a considerable socio-economic impact. Over 50% of patients presenting in primary care still have symptoms after 6 months; moreover, prognostic factors such as pain intensity, age, disability level and duration of complaints are associated with poor outcome. Most shoulder complaints in this group are categorized as non-specific. Musculoskeletal ultrasound might be a useful imaging method to detect subgroups of patients with subacromial disorders.This article describes the design of a prospective cohort study evaluating the influence of known prognostic and possible prognostic factors, such as findings from musculoskeletal ultrasound outcome and working alliance, on the recovery of shoulder pain. Also, to assess the usual physiotherapy care for shoulder pain and examine the inter-rater reliability of musculoskeletal ultrasound between radiologists and physiotherapists for patients with shoulder pain. A prospective cohort study including an inter-rater reliability study. Patients presenting in primary care physiotherapy practice with shoulder pain are enrolled. At baseline validated questionnaires are used to measure patient characteristics, disease-specific characteristics and social factors. Physical examination is performed according to the expertise of the physiotherapists. Follow-up measurements will be performed 6, 12 and 26 weeks after inclusion. Primary outcome measure is perceived recovery, measured on a 7-point Likert scale. Logistic regression analysis will be used to evaluate the association between prognostic factors and recovery. The ShoCoDiP (Shoulder Complaints and using Diagnostic ultrasound in Physiotherapy practice) cohort study will provide information on current management of patients with shoulder pain in primary care, provide data to develop a prediction model for shoulder pain in primary care and to evaluate whether musculoskeletal ultrasound can improve prognosis.

Cohort Profile : LifeLines, a three-generation cohort study and biobank

NARCIS (Netherlands)

Scholtens, Salome; Smidt, Nynke; Swertz, Morris A.; Bakker, Stephan J. L.; Dotinga, Aafje; Vonk, Judith M.; van Dijk, Freerk; van Zon, Sander K. R.; Wijmenga, Cisca; Wolffenbuttel, Bruce H. R.; Stolk, Ronald P.

The LifeLines Cohort Study is a large population-based cohort study and biobank that was established as a resource for research on complex interactions between environmental, phenotypic and genomic factors in the development of chronic diseases and healthy ageing. Between 2006 and 2013, inhabitants

Cohort profile: the lidA Cohort Study-a German Cohort Study on Work, Age, Health and Work Participation.

Science.gov (United States)

Hasselhorn, Hans Martin; Peter, Richard; Rauch, Angela; Schröder, Helmut; Swart, Enno; Bender, Stefan; du Prel, Jean-Baptist; Ebener, Melanie; March, Stefanie; Trappmann, Mark; Steinwede, Jacob; Müller, Bernd Hans

2014-12-01

The lidA Cohort Study (German Cohort Study on Work, Age, Health and Work Participation) was set up to investigate and follow the effects of work and work context on the physical and psychological health of the ageing workforce in Germany and subsequently on work participation. Cohort participants are initially employed people subject to social security contributions and born in either 1959 (n = 2909) or 1965 (n = 3676). They were personally interviewed in their homes in 2011 and will be visited every 3 years. Data collection comprises socio-demographic data, work and private exposures, work ability, work and work participation attitudes, health, health-related behaviour, personality and attitudinal indicators. Employment biographies are assessed using register data. Subjective health reports and physical strength measures are complemented by health insurance claims data, where permission was given. A conceptual framework has been developed for the lidA Cohort Study within which three confirmatory sub-models assess the interdependencies of work and health considering age, gender and socioeconomic status. The first set of the data will be available to the scientific community by 2015. Access will be given by the Research Data Centre of the German Federal Employment Agency at the Institute for Employment Research (http://fdz.iab.de/en.aspx). © The Author 2014. Published by Oxford University Press on behalf of the International Epidemiological Association.

Prognosis of acute low back pain: design of a prospective inception cohort study

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York John

2006-06-01

Full Text Available Abstract Background Clinical guidelines generally portray acute low back pain as a benign and self-limiting condition. However, evidence about the clinical course of acute low back pain is contradictory and the risk of subsequently developing chronic low back pain remains uncertain. There are few high quality prognosis studies and none that have measured pain, disability and return to work over a 12 month period. This study aims to provide the first estimates of the one year prognosis of acute low back pain (pain of less than 2 weeks duration in patients consulting primary care practitioners. A secondary aim is to identify factors that are associated with the prognosis of low back pain. Methods/Design The study is a prospective inception cohort study. Consecutive patients consulting general medical practitioners, physiotherapists and chiropractors in the Sydney metropolitan region will complete a baseline questionnaire regarding their back pain. Subsequently these patients will be followed up by telephone 6 weeks, 3 months and 12 months after the initial consultation. Patients will be considered to have recovered from the episode of back pain if they have no pain and no limitation of activity, and have returned to pre-injury work status. Life tables will be generated to determine the one year prognosis of acute low back pain. Prognostic factors will be assessed using Cox regression. Discussion This study will provide the first estimates of the one year prognosis of acute low back pain in a representative sample of primary care patients.

Subclinical Hyperthyroidism-A Cohort Study

International Nuclear Information System (INIS)

Hashim, R.; Anwer, M. S.; Khan, F. A.; Ijaz, A.

2013-01-01

Objective: To compare the development of overt hyperthyroidism in a cohort of patients of subclinical hyperthyroidism (SCR) and in subjects with normal thyroid function tests. Study Design: A cohort study. Place and Duration of study: The study was conducted in the department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology, Rawalpindi from Sept 2006 to Sept 2007. Patients and Methods: Fifty patients of SCR and almost equal number of age and sex-matched subjects with normal Thyroid function test (TFT) were included in the study as controls. Subclinical hyperthyroid patients and controls were followed for a period of one year on a six monthly basis. The patients were examined for signs and symptoms of hyperthyroidism and serum TSH, total T3 and free T4 were estimated. The clinical history, physical examination and TFT results were recorded. Five ml of blood was collected for serum thyroid profile in plain tube. Hormonal analysis(TSH, T4 and T3) was done for the patients and the controls enrolled in the study. The TFTs was analyzed using Chemiluminescence Immunoassay technique on Immulite 2000 an automated, random access, immunoassay analyzer. Results: Six (12%) out of 50 cases of the SCR patients and 2 (4%) out of 50 controls developed overt hyperthyroidism. SCR had no significant risk for conversion to overt hyperthyroidism as compared to healthy controls in this study. In addition to initial levels of serum TSH were one of important predictor for conversion of SCR to overt hyperthyroidism. Conclusion: Patients with SCR have no significant risk but showed an increase in frequency of conversion to overt hyperthyroidism (12% in this study) as compared to controls. (author)

The International Childhood Cardiovascular Cohort (i3C) consortium outcomes study of childhood cardiovascular risk factors and adult cardiovascular morbidity and mortality: Design and recruitment.

Science.gov (United States)

Sinaiko, Alan R; Jacobs, David R; Woo, Jessica G; Bazzano, Lydia; Burns, Trudy; Hu, Tian; Juonala, Markus; Prineas, Ronald; Raitakari, Olli; Steinberger, Julia; Urbina, Elaine; Venn, Alison; Jaquish, Cashell; Dwyer, Terry

2018-04-22

Although it is widely thought that childhood levels of cardiovascular (CV) risk factors are related to adult CV disease, longitudinal data directly linking the two are lacking. This paper describes the design and organization of the International Childhood Cardiovascular Cohort Consortium Outcomes Study (i3C Outcomes), the first longitudinal cohort study designed to locate adults with detailed, repeated, childhood biological, physical, and socioeconomic measurements and a harmonized database. I3C Outcomes uses a Heart Health Survey (HHS) to obtain information on adult CV endpoints, using mail, email, telephone, and clinic visits in the United States (U.S.) and Australia and a national health database in Finland. Microsoft Access, REsearch Data Capture (REDCap) (U.S.), LimeSurvey (Australia), and Medidata™ Rave data systems are used to collect, transfer and organize data. Self-reported CV events are adjudicated via hospital and doctor-released medical records. After the first two study years, participants (N = 10,968) were more likely to be female (56% vs. 48%), non-Hispanic white (90% vs. 80%), and older (10.4 ± 3.8 years vs. 9.4 ± 3.3 years) at their initial childhood study visit than the currently non-recruited cohort members. Over 48% of cohort members seen during both adulthood and childhood have been found and recruited, to date, vs. 5% of those not seen since childhood. Self-reported prevalences were 0.7% Type 1 Diabetes, 7.5% Type 2 Diabetes, 33% hypertension, and 12.8% CV event. 32% of CV events were judged to be true. I3C Outcomes is uniquely able to establish evidence-based guidelines for child health care and to clarify relations to adult CV disease. Copyright © 2018 Elsevier Inc. All rights reserved.

Study designs may influence results

DEFF Research Database (Denmark)

Johansen, Christoffer; Schüz, Joachim; Andreasen, Anne-Marie Serena

2017-01-01

appeared to show an inverse association, whereas nested case-control and cohort studies showed no association. For allergies, the inverse association was observed irrespective of study design. We recommend that the questionnaire-based case-control design be placed lower in the hierarchy of studies...... for establishing cause-and-effect for diseases such as glioma. We suggest that a state-of-the-art case-control study should, as a minimum, be accompanied by extensive validation of the exposure assessment methods and the representativeness of the study sample with regard to the exposures of interest. Otherwise...

Male sleep duration and fecundability in a North American preconception cohort study

DEFF Research Database (Denmark)

Wise, Lauren Anne; Rothman, Kenneth Jay; Wesselink, Amelia Kent

2018-01-01

OBJECTIVE: To evaluate prospectively the association between male sleep duration and fecundability. DESIGN: Pregnancy Online Study (PRESTO), a Web-based prospective cohort study of North American couples enrolled during the preconception period (2013-2017). SETTING: Not applicable. PATIENT(S): Male...

The Danish National Birth Cohort

DEFF Research Database (Denmark)

Andersen, Anne-Marie Nybo; Olsen, Jørn

2011-01-01

, physical exercise, working conditions, medication and infections during pregnancy, and environmental possible toxins. The study designs cover straightforward cohort analyses, case-control studies and sub-cohort analyses with enriched data collection. CONCLUSION: So far, the Danish National Birth Cohort has......INTRODUCTION: In this review a selection of studies published during the period 2002-2010, based on data from the Danish National Birth Cohort linked with other health registers, is described. Illustrative examples of studies addressing perinatal health outcomes (pregnancy complications and fetal...... that this investment in epidemiologic infrastructure was well spent. The existence of the Danish National Birth Cohort together with other cohorts and national registers has given Denmark a leading position in reproductive epidemiology....

Canadian Alliance for Healthy Hearts and Minds: First Nations Cohort Study Rationale and Design.

Science.gov (United States)

Anand, Sonia S; Abonyi, Sylvia; Arbour, Laura; Brook, Jeff; Bruce, Sharon; Castleden, Heather; Desai, Dipika; de Souza, Russell J; Harris, Stewart; Irvine, James; Lai, Christopher; Lewis, Diana; Oster, Richard T; Poirier, Paul; Toth, Ellen L; Bannon, Karen; Chrisjohn, Vicky; Davis, Albertha D; L'Hommecourt, Jean; Littlechild, Randy; McMullin, Kathleen; McIntosh, Sarah; Morrison, Julie; Picard, Manon; Landing First Nation, Pictou; M Thomas, Melissa; Tusevljak, Natasa; Friedrich, Matthias G; Tu, Jack V

2018-01-01

This is the first national indigenous cohort study in which a common, in-depth protocol with a common set of objectives has been adopted by several indigenous communities across Canada. The overarching objective of the Canadian Alliance for Healthy Hearts and Minds (CAHHM) cohort is to investigate how the community-level environment is associated with individual health behaviors and the presence and progression of chronic disease risk factors and chronic diseases such as cardiovascular disease (CVD) and cancer. CAHHM aims to recruit approximately 2,000 First Nations indigenous individuals from up to nine communities across Canada and have participants complete questionnaires, blood collection, physical measurements, cognitive assessments, and magnetic resonance imaging (MRI). Through individual- and community-level data collection, we will develop an understanding of the specific role of the socioenvironmental, biological, and contextual factors have on the development of chronic disease risk factors and chronic diseases. Information collected in the indigenous cohort will be used to assist communities to develop local management strategies for chronic disease, and can be used collectively to understand the contextual, environmental, socioeconomic, and biological determinants of differences in health status in harmony with First Nations beliefs and reality.

Study of Women, Infant feeding, and Type 2 diabetes mellitus after GDM pregnancy (SWIFT, a prospective cohort study: methodology and design

Directory of Open Access Journals (Sweden)

Gunderson Erica P

2011-12-01

Full Text Available Abstract Background Women with history of gestational diabetes mellitus (GDM are at higher risk of developing type 2 diabetes within 5 years after delivery. Evidence that lactation duration influences incident type 2 diabetes after GDM pregnancy is based on one retrospective study reporting a null association. The Study of Women, Infant Feeding and Type 2 Diabetes after GDM pregnancy (SWIFT is a prospective cohort study of postpartum women with recent GDM within the Kaiser Permanente Northern California (KPNC integrated health care system. The primary goal of SWIFT is to assess whether prolonged, intensive lactation as compared to formula feeding reduces the 2-year incidence of type 2 diabetes mellitus among women with GDM. The study also examines whether lactation intensity and duration have persistent favorable effects on blood glucose, insulin resistance, and adiposity during the 2-year postpartum period. This report describes the design and methods implemented for this study to obtain the clinical, biochemical, anthropometric, and behavioral measurements during the recruitment and follow-up phases. Methods SWIFT is a prospective, observational cohort study enrolling and following over 1, 000 postpartum women diagnosed with GDM during pregnancy within KPNC. The study enrolled women at 6-9 weeks postpartum (baseline who had been diagnosed by standard GDM criteria, aged 20-45 years, delivered a singleton, term (greater than or equal to 35 weeks gestation live birth, were not using medications affecting glucose tolerance, and not planning another pregnancy or moving out of the area within the next 2 years. Participants who are free of type 2 diabetes and other serious medical conditions at baseline are screened for type 2 diabetes annually within the first 2 years after delivery. Recruitment began in September 2008 and ends in December 2011. Data are being collected through pregnancy and early postpartum telephone interviews, self

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

Falls in people with chronic obstructive pulmonary disease: An observational cohort study

DEFF Research Database (Denmark)

Roig, Marc; Eng, Janice J; MacIntyre, Donna L

2011-01-01

STUDY OBJECTIVE: To investigate incidence, risk factors and impact of falls on health related quality of life (HRQoL) in patients with chronic obstructive pulmonary disease (COPD). DESIGN: Observational cohort study. METHODS: Patients completed these questionnaires at baseline and at 6-months...

Design, methods and demographics from phase I of Alberta's Tomorrow Project cohort: a prospective cohort profile.

Science.gov (United States)

Robson, Paula J; Solbak, Nathan M; Haig, Tiffany R; Whelan, Heather K; Vena, Jennifer E; Akawung, Alianu K; Rosner, William K; Brenner, Darren R; Cook, Linda S; Csizmadi, Ilona; Kopciuk, Karen A; McGregor, S Elizabeth; Friedenreich, Christine M

2016-01-01

Prospective cohorts have the potential to support multifactorial, health-related research, particularly if they are drawn from the general population, incorporate active and passive follow-up and permission is obtained to allow access by researchers to data repositories. This paper describes Phase I of the Alberta's Tomorrow Project cohort, a broad-based research platform designed to support investigations into factors that influence cancer and chronic disease risk. Adults aged 35-69 years living in Alberta, Canada, with no previous cancer diagnosis other than nonmelanoma skin cancer were recruited to the project by telephone-based random digit dialling. Participants were enrolled if they returned a Health and Lifestyle Questionnaire. Past year diet and physical activity questionnaires were mailed 3 months after enrolment. Consent was sought for active follow-up and linkage with administrative databases. Depending on enrolment date, participants were invited to complete up to 2 follow-up questionnaires (2004 and 2008). Between 2001 and 2009, 31 072 (39% men) participants (mean age 50.2 [± 9.2] yr) were enrolled and 99% consented to linkage with administrative databases. Participants reported a wide range of educational attainment and household income. Compared with provincial surveillance data from the Canadian Community Health Survey, Alberta's Tomorrow Project participants had higher body mass index, lower prevalence of smoking and similar distribution of chronic health conditions. Follow-up questionnaires were completed by 83% and 72% of participants in 2004 and 2008, respectively. Robust quality control measures resulted in low frequencies of missing data. Alberta's Tomorrow Project provides a robust platform, based on a prospective cohort design, to support research into risk factors for cancer and chronic disease.

Evaluation of statistical designs in phase I expansion cohorts: the Dana-Farber/Harvard Cancer Center experience.

Science.gov (United States)

Dahlberg, Suzanne E; Shapiro, Geoffrey I; Clark, Jeffrey W; Johnson, Bruce E

2014-07-01

Phase I trials have traditionally been designed to assess toxicity and establish phase II doses with dose-finding studies and expansion cohorts but are frequently exceeding the traditional sample size to further assess endpoints in specific patient subsets. The scientific objectives of phase I expansion cohorts and their evolving role in the current era of targeted therapies have yet to be systematically examined. Adult therapeutic phase I trials opened within Dana-Farber/Harvard Cancer Center (DF/HCC) from 1988 to 2012 were identified for sample size details. Statistical designs and study objectives of those submitted in 2011 were reviewed for expansion cohort details. Five hundred twenty-two adult therapeutic phase I trials were identified during the 25 years. The average sample size of a phase I study has increased from 33.8 patients to 73.1 patients over that time. The proportion of trials with planned enrollment of 50 or fewer patients dropped from 93.0% during the time period 1988 to 1992 to 46.0% between 2008 and 2012; at the same time, the proportion of trials enrolling 51 to 100 patients and more than 100 patients increased from 5.3% and 1.8%, respectively, to 40.5% and 13.5% (χ(2) test, two-sided P < .001). Sixteen of the 60 trials (26.7%) in 2011 enrolled patients to three or more sub-cohorts in the expansion phase. Sixty percent of studies provided no statistical justification of the sample size, although 91.7% of trials stated response as an objective. Our data suggest that phase I studies have dramatically changed in size and scientific scope within the last decade. Additional studies addressing the implications of this trend on research processes, ethical concerns, and resource burden are needed. © The Author 2014. Published by Oxford University Press. All rights reserved.

The Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases: study design and baseline characteristics.

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Lixin Na

Full Text Available Diet and nutrition have been reported to be associated with many common chronic diseases and blood-based assessment would be vital to investigate the association and mechanism, however, blood-based prospective studies are limited. The Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases was set up in 2010. From 2010 to 2012, 9,734 participants completed the baseline survey, including demographic characteristics, dietary intake, lifestyles and physical condition, and anthropometrics. A re-survey on 490 randomly selected participants was done by using the same methods which were employed in the baseline survey. For all participants, the mean age was 50 years and 36% of them were men. Approximately 99.4 % of cohort members donated blood samples. The mean total energy intake was 2671.7 kcal/day in men and 2245.9 kcal/day in women, the mean body mass index was 25.7 kg/m2 in men and 24.6 kg/m2 in women, with 18.4% being obese (≥ 28 kg/m2, 12.7% being diabetic, and 29.5% being hypertensive. A good agreement was obtained for the physical measurements between the baseline survey and re-survey. The resources from the cohort and its fasting and postprandial blood samples collected both at baseline and in each follow-up will be valuable and powerful in investigating relationship between diet, nutrition and chronic diseases and discovering novel blood biomarkers and the metabolism of these biomarkers related to chronic diseases.

The Urban Environment and Childhood Asthma (URECA birth cohort study: design, methods, and study population

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Sandel Megan T

2009-05-01

Full Text Available Abstract Background The incidence and morbidity of wheezing illnesses and childhood asthma is especially high in poor urban areas. This paper describes the study design, methods, and population of the Urban Environment and Childhood Asthma (URECA study, which was established to investigate the immunologic causes of asthma among inner-city children. Methods and Results URECA is an observational prospective study that enrolled pregnant women in central urban areas of Baltimore, Boston, New York City, and St. Louis and is following their offspring from birth through age 7 years. The birth cohort consists of 560 inner-city children who have at least one parent with an allergic disease or asthma, and all families live in areas in which at least 20% of the population has incomes below the poverty line. In addition, 49 inner-city children with no parental history of allergies or asthma were enrolled. The primary hypothesis is that specific urban exposures in early life promote a unique pattern of immune development (impaired antiviral and increased Th2 responses that increases the risk of recurrent wheezing and allergic sensitization in early childhood, and of asthma by age 7 years. To track immune development, cytokine responses of blood mononuclear cells stimulated ex vivo are measured at birth and then annually. Environmental assessments include allergen and endotoxin levels in house dust, pre- and postnatal maternal stress, and indoor air nicotine and nitrogen dioxide. Nasal mucous samples are collected from the children during respiratory illnesses and analyzed for respiratory viruses. The complex interactions between environmental exposures and immune development will be assessed with respect to recurrent wheeze at age 3 years and asthma at age 7 years. Conclusion The overall goal of the URECA study is to develop a better understanding of how specific urban exposures affect immune development to promote wheezing illnesses and asthma.

The LifeLines Cohort Study: Prevalence and treatment of cardiovascular disease and risk factors

OpenAIRE

van der Ende, M. Yldau; Hartman, Minke H. T.; Hagemeijer, Yanick; Meems, Laura M. G.; de Vries, Hendrik Sierd; Stolk, Ronald P.; de Boer, Rudolf A.; Sijtsma, Anna; van der Meer, Peter; Rienstra, Michiel; van der Harst, Pim

2017-01-01

Background: The LifeLines Cohort Study is a large three-generation prospective study and Biobank. Recruitment and data collection started in 2006 and follow-up is planned for 30 years. The central aim of LifeLines is to understand healthy ageing in the 21st century. Here, the study design, methods, baseline and major cardiovascular phenotypes of the LifeLines Cohort Study are presented. Methods and results: Baseline cardiovascular phenotypeswere defined in 9700 juvenile (8-18 years) and 152,1...

Transcranial direct-current stimulation induced in stroke patients with aphasia: a prospective experimental cohort study

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Santos,Michele Devido; Gagliardi,Rubens José; Mac-Kay,Ana Paula Machado Goyano; Boggio,Paulo Sergio; Lianza,Roberta; Fregni,Felipe

2013-01-01

CONTEXT AND OBJECTIVE: Previous animal and human studies have shown that transcranial direct current stimulation can induce significant and lasting neuroplasticity and may improve language recovery in patients with aphasia. The objective of the study was to describe a cohort of patients with aphasia after stroke who were treated with transcranial direct current stimulation. DESIGN AND SETTING: Prospective cohort study developed in a public university hospital. METHODS: Nineteen patients with ...

Life-course pathways to psychological distress: A cohort study

OpenAIRE

Von Stumm, S.; Deary, I. J.; Hagger-Johnson, G.

2013-01-01

Abstract: Objectives: Early life factors, like intelligence and socioeconomic status (SES), are associated with health outcomes in adulthood. Fitting comprehensive life-course models, we tested (1) the effect of childhood intelligence and SES, education and adulthood SES on psychological distress at midlife, and (2) compared alternative measurement specifications (reflective and formative) of SES. Design: Prospective cohort study (the Aberdeen Children of the 1950s). Setting: Aberdeen, Scotla...

[Application of cohort study in cancer prevention and control].

Science.gov (United States)

Dai, Min; Bai, Yana; Pu, Hongquan; Cheng, Ning; Li, Haiyan; He, Jie

2016-03-01

Cancer control is a long-term work. Cancer research and intervention really need the support of cohort study. In the recent years, more and more cohort studies on cancer control were conducted in China along with the increased ability of scientific research in China. Since 2010, Cancer Hospital, Chinese Academy of Medical Sciences, collaborated with Lanzhou University and the Worker' s Hospital of Jinchuan Group Company Limited, have carried out a large-scale cohort study on cancer, which covered a population of more than 50 000 called " Jinchang cohort". Since 2012, a National Key Public Health Project, "cancer screening in urban China" , has been conducted in Jinchang, which strengthened the Jinchang cohort study. Based on the Jinchang cohort study, historical cohort study, cross-sectional study and prospective cohort study have been conducted, which would provide a lot of evidence for the cancer control in China.

Coffee drinking and mortality in 10 European countries : A multinational cohort study

NARCIS (Netherlands)

Gunter, Marc J.; Murphy, Neil; Cross, Amanda J.; Dossus, Laure; Dartois, Laureen; Fagherazzi, Guy; Kaaks, Rudolf; Kühn, Tilman; Boeing, Heiner; Aleksandrova, Krasimira; Tjønneland, Anne; Olsen, Anja; Overvad, Kim; Larsen, Sofus Christian; Cornejo, Maria Luisa Redondo; Agudo, Antonio; Pérez, María José Sánchez; Altzibar, Jone M.; Navarro, Carmen; Ardanaz, Eva; Khaw, Kay Tee; Butterworth, Adam; Bradbury, Kathryn E.; Trichopoulou, Antonia; Lagiou, Pagona; Trichopoulos, Dimitrios; Palli, Domenico; Grioni, Sara; Vineis, Paolo; Panico, Salvatore; Tumino, Rosario; Bueno-De-Mesquita, Bas; Siersema, Peter; Leenders, Max; Beulens, Joline W.J.; Uiterwaal, Cuno U.; Wallström, Peter; Nilsson, Lena Maria; Landberg, Rikard; Weiderpass, Elisabete; Skeie, Guri; Braaten, Tonje; Brennan, Paul; Licaj, Idlir; Muller, David C.; Sinha, Rashmi; Wareham, Nick; Riboli, Elio

2017-01-01

Background: The relationship between coffee consumption and mortality in diverse European populations with variable coffee preparation methods is unclear. Objective: To examine whether coffee consumption is associated with all-cause and cause-specific mortality. Design: Prospective cohort study.

Research designs and making causal inferences from health care studies.

Science.gov (United States)

Flannelly, Kevin J; Jankowski, Katherine R B

2014-01-01

This article summarizes the major types of research designs used in healthcare research, including experimental, quasi-experimental, and observational studies. Observational studies are divided into survey studies (descriptive and correlational studies), case-studies and analytic studies, the last of which are commonly used in epidemiology: case-control, retrospective cohort, and prospective cohort studies. Similarities and differences among the research designs are described and the relative strength of evidence they provide is discussed. Emphasis is placed on five criteria for drawing causal inferences that are derived from the writings of the philosopher John Stuart Mill, especially his methods or canons. The application of the criteria to experimentation is explained. Particular attention is given to the degree to which different designs meet the five criteria for making causal inferences. Examples of specific studies that have used various designs in chaplaincy research are provided.

Alcohol attributable burden of incidence of cancer in eight European countries based on results from prospective cohort study

NARCIS (Netherlands)

Schuetze, Madlen; Boeing, Heiner; Pischon, Tobias; Rehm, Juergen; Kehoe, Tara; Gmel, Gerrit; Olsen, Anja; Tjonneland, Anne M.; Dahm, Christina C.; Overvad, Kim; Clavel-Chapelon, Francoise; Boutron-Ruault, Marie-Christine; Trichopoulou, Antonia; Benetou, Vasiliki; Zylis, Dimosthenis; Kaaks, Rudolf; Rohrmann, Sabine; Palli, Domenico; Berrino, Franco; Tumino, Rosario; Vineis, Paolo; Rodriguez, Laudina; Agudo, Antonio; Sanchez, Maria-Jose; Dorronsoro, Miren; Chirlaque, Maria-Dolores; Barricarte, Aurelio; Peeters, Petra H.; van Gils, Carla H.; Khaw, Kay-Tee; Wareham, Nick; Allen, Naomi E.; Key, Timothy J.; Boffetta, Paolo; Slimani, Nadia; Jenab, Mazda; Romaguera, Dora; Wark, Petra A.; Riboli, Elio; Bergmann, Manuela M.

2011-01-01

Objective To compute the burden of cancer attributable to current and former alcohol consumption in eight European countries based on direct relative risk estimates from a cohort study. Design Combination of prospective cohort study with representative population based data on alcohol exposure.

The Congenital Heart Disease Genetic Network Study: Cohort description.

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Thanh T Hoang

Full Text Available The Pediatric Cardiac Genomics Consortium (PCGC designed the Congenital Heart Disease Genetic Network Study to provide phenotype and genotype data for a large congenital heart defects (CHDs cohort. This article describes the PCGC cohort, overall and by major types of CHDs (e.g., conotruncal defects and subtypes of conotrucal heart defects (e.g., tetralogy of Fallot and left ventricular outflow tract obstructions (e.g., hypoplastic left heart syndrome. Cases with CHDs were recruited through ten sites, 2010-2014. Information on cases (N = 9,727 and their parents was collected through interviews and medical record abstraction. Four case characteristics, eleven parental characteristics, and thirteen parent-reported neurodevelopment outcomes were summarized using counts and frequencies and compared across CHD types and subtypes. Eleven percent of cases had a genetic diagnosis. Among cases without a genetic diagnosis, the majority had conotruncal heart defects (40% or left ventricular outflow tract obstruction (21%. Across CHD types, there were significant differences (p<0.05 in the distribution of all four case characteristics (e.g., sex, four parental characteristics (e.g., maternal pregestational diabetes, and five neurodevelopmental outcomes (e.g., learning disabilities. Several characteristics (e.g., sex were also significantly different across CHD subtypes. The PCGC cohort is one of the largest CHD cohorts available for the study of genetic determinants of risk and outcomes. The majority of cases do not have a genetic diagnosis. This description of the PCGC cohort, including differences across CHD types and subtypes, provides a reference work for investigators who are interested in collaborating with or using publically available resources from the PCGC.

[Ethical considerations in genomic cohort study].

Science.gov (United States)

Choi, Eun Kyung; Kim, Ock-Joo

2007-03-01

During the last decade, genomic cohort study has been developed in many countries by linking health data and genetic data in stored samples. Genomic cohort study is expected to find key genetic components that contribute to common diseases, thereby promising great advance in genome medicine. While many countries endeavor to build biobank systems, biobank-based genome research has raised important ethical concerns including genetic privacy, confidentiality, discrimination, and informed consent. Informed consent for biobank poses an important question: whether true informed consent is possible in population-based genomic cohort research where the nature of future studies is unforeseeable when consent is obtained. Due to the sensitive character of genetic information, protecting privacy and keeping confidentiality become important topics. To minimize ethical problems and achieve scientific goals to its maximum degree, each country strives to build population-based genomic cohort research project, by organizing public consultation, trying public and expert consensus in research, and providing safeguards to protect privacy and confidentiality.

Recovery of standing balance in postacute stroke patients: a rehabilitation cohort study

NARCIS (Netherlands)

de Haart, Mirjam; Geurts, Alexander C.; Huidekoper, Steven C.; Fasotti, Luciano; van Limbeek, Jacques

2004-01-01

OBJECTIVE: To identify and interrelate static and dynamic characteristics of the restoration of quiet standing balance in a representative sample of stroke survivors in the Netherlands during their inpatient rehabilitation. DESIGN: Exploratory study using an inception cohort with findings related to

Adverse drug reactions to tocolytic treatment for preterm labour: Prospective cohort study

NARCIS (Netherlands)

R. de Heus (Roel); B.W.J. Mol (Ben); J.J.H.M. Erwich; H.P. van Geijn (Herman); W.J. Gyselaers (Wilfried); M. Hanssens (Myriam); L. Harmark (Linda); C.D. van Holsbeke (Caroline); J.J. Duvekot (Hans); F. Famschobben; H. Wolf (Hans Uwe); G.H. Visser (Gerhard Henk)

2009-01-01

textabstractObjective To evaluate the incidence of serious maternal complications after the use of various tocolytic drugs for the treatment of preterm labour in routine clinical situations. Design Prospective cohort study. Setting 28 hospitals in the Netherlands and Belgium. Participants 1920

The study design and methodology for the ARCHER study - adolescent rural cohort study of hormones, health, education, environments and relationships

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Steinbeck Katharine

2012-09-01

Full Text Available Abstract Background Adolescence is characterized by marked psychosocial, behavioural and biological changes and represents a critical life transition through which adult health and well-being are established. Substantial research confirms the role of psycho-social and environmental influences on this transition, but objective research examining the role of puberty hormones, testosterone in males and oestradiol in females (as biomarkers of puberty on adolescent events is lacking. Neither has the tempo of puberty, the time from onset to completion of puberty within an individual been studied, nor the interaction between age of onset and tempo. This study has been designed to provide evidence on the relationship between reproductive hormones and the tempo of their rise to adult levels, and adolescent behaviour, health and wellbeing. Methods/Design The ARCHER study is a multidisciplinary, prospective, longitudinal cohort study in 400 adolescents to be conducted in two centres in regional Australia in the State of New South Wales. The overall aim is to determine how changes over time in puberty hormones independently affect the study endpoints which describe universal and risk behaviours, mental health and physical status in adolescents. Recruitment will commence in school grades 5, 6 and 7 (10–12 years of age. Data collection includes participant and parent questionnaires, anthropometry, blood and urine collection and geocoding. Data analysis will include testing the reliability and validity of the chosen measures of puberty for subsequent statistical modeling to assess the impact over time of tempo and onset of puberty (and their interaction and mean-level repeated measures analyses to explore for significant upward and downward shifts on target outcomes as a function of main effects. Discussion The strengths of this study include enrollment starting in the earliest stages of puberty, the use of frequent urine samples in addition to annual

Rationale, design, and preliminary results of the Quebec Warfarin Cohort Study.

Science.gov (United States)

Perreault, Sylvie; Shahabi, Payman; Côté, Robert; Dumas, Stéphanie; Rouleau-Mailloux, Étienne; Feroz Zada, Yassamin; Provost, Sylvie; Mongrain, Ian; Dorais, Marc; Huynh, Thao; Kouz, Simon; Diaz, Ariel; Blostein, Mark; de Denus, Simon; Turgeon, Jacques; Ginsberg, Jeffrey; Lelorier, Jacques; Lalonde, Lyne; Busque, Lambert; Kassis, Jeannine; Talajic, Mario; Tardif, Jean-Claude; Dubé, Marie-Pierre

2018-05-01

Over- and undercoagulation with warfarin are associated with hemorrhagic and thromboembolic events, respectively. Genetic and clinical factors affect warfarin response, and the causes of this variability remain unclear. We present descriptive statistics and test for predictors of poor anticoagulation control. The Quebec Warfarin Cohort (QWC) comprises 1059 new warfarin users, with prospective follow-up using telephone questionnaires every 3 months for 1 year, and using healthcare administrative databases (RAMQ and Med-Echo) for 5 years prior to cohort entry and up to 10 years following active patient participation. Genetic material was collected, and genotyping of CYP2C9 and VKORC1 genes was conducted. Measured outcomes included the percentage of time patients spent within therapeutic range, anticoagulation control, warfarin dose, bleeding, and thromboembolic events. We report baseline characteristics and outcomes after 1 year of follow-up. Poor anticoagulation control was defined as time in therapeutic range <60% in the 3- to 12-month interval. Participants had a mean age of 71 years, and 62% were men. The most common indication for warfarin was atrial fibrillation (87%). Mean time in therapeutic range was 56% (±25%) in the 3 months following warfarin initiation, and 70% (±21%) in the 3- to 12-month interval. During follow-up, the rate of stroke or systemic embolism was 1.8 events per 100 person-years; for major bleeding events, 3.3 events per 100 person-years. Independent predictors of poor anticoagulation control were chronic kidney disease, heart failure, dyslipidemia, and age. The QWC represents a good research cohort to investigate clinical and genetic factors in a warfarin-anticoagulated population. © 2018 Wiley Periodicals, Inc.

Influence of the Size of Cohorts in Adaptive Design for Nonlinear Mixed Effects Models: An Evaluation by Simulation for a Pharmacokinetic and Pharmacodynamic Model for a Biomarker in Oncology

Science.gov (United States)

Lestini, Giulia; Dumont, Cyrielle; Mentré, France

2015-01-01

Purpose In this study we aimed to evaluate adaptive designs (ADs) by clinical trial simulation for a pharmacokinetic-pharmacodynamic model in oncology and to compare them with one-stage designs, i.e. when no adaptation is performed, using wrong prior parameters. Methods We evaluated two one-stage designs, ξ0 and ξ*, optimised for prior and true population parameters, Ψ0 and Ψ*, and several ADs (two-, three- and five-stage). All designs had 50 patients. For ADs, the first cohort design was ξ0. The next cohort design was optimised using prior information updated from the previous cohort. Optimal design was based on the determinant of the Fisher information matrix using PFIM. Design evaluation was performed by clinical trial simulations using data simulated from Ψ*. Results Estimation results of two-stage ADs and ξ* were close and much better than those obtained with ξ0. The balanced two-stage AD performed better than two-stage ADs with different cohort sizes. Three-and five-stage ADs were better than two-stage with small first cohort, but not better than the balanced two-stage design. Conclusions Two-stage ADs are useful when prior parameters are unreliable. In case of small first cohort, more adaptations are needed but these designs are complex to implement. PMID:26123680

Improving return-to-work after childbirth: design of the Mom@Work study, a randomised controlled trial and cohort study.

Science.gov (United States)

Stomp-van den Berg, Suzanne G M; van Poppel, Mireille N M; Hendriksen, Ingrid J M; Bruinvels, David J; Uegaki, Kimi; de Bruijne, Martine C; van Mechelen, Willem

2007-03-29

Many women suffer from health problems after giving birth, which can lead to sick leave. About 30% of Dutch workers are on sick leave after maternity leave. Structural contact of supervisors with employees on maternity leave, supported by early medical advice of occupational physicians, may increase the chances of return-to-work after maternity leave. In addition, to understand the process of sick leave and return-to-work after childbirth it is important to gain insight into which factors hinder return-to-work after childbirth, as well, as which prognostic factors lead to the development of postpartum health complaints. In this paper, the design of the Mom@Work study is described. The Mom@Work study is simultaneously a randomised controlled trial and a cohort study. Pregnant women working for at least 12 hours a week at one of the 15 participating companies are eligible to participate. The supervisors of these pregnant employees are randomised at 35 weeks pregnancy into the intervention group or control group. During maternity leave, supervisors in the intervention group contact their employee six weeks after delivery using a structured interview. When employees do not expect to return to their jobs at the end of their scheduled maternity leave due to health problems, the supervisor offers early support of the occupational physician. Supervisors in the control group have no structural contact with their employees during maternity leave. Measurements take place at 30 weeks pregnancy and at 6, 12, 24 and 52 weeks postpartum. In addition, cost data are collected. For the RCT, primary outcome measures are sick leave and return-to-work, and secondary outcome measures are costs, health, satisfaction with intervention and global feelings of recovery. Outcome measures for the cohort are pregnancy-related pelvic girdle pain, fatigue and depression. Finally, a number of prognostic factors for return-to-work and for the development of complaints will be measured. The Mom

Improving return-to-work after childbirth: design of the Mom@Work study, a randomised controlled trial and cohort study

Directory of Open Access Journals (Sweden)

Bruinvels David J

2007-03-01

Full Text Available Abstract Background Many women suffer from health problems after giving birth, which can lead to sick leave. About 30% of Dutch workers are on sick leave after maternity leave. Structural contact of supervisors with employees on maternity leave, supported by early medical advice of occupational physicians, may increase the chances of return-to-work after maternity leave. In addition, to understand the process of sick leave and return-to-work after childbirth it is important to gain insight into which factors hinder return-to-work after childbirth, as well, as which prognostic factors lead to the development of postpartum health complaints. In this paper, the design of the Mom@Work study is described. Methods The Mom@Work study is simultaneously a randomised controlled trial and a cohort study. Pregnant women working for at least 12 hours a week at one of the 15 participating companies are eligible to participate. The supervisors of these pregnant employees are randomised at 35 weeks pregnancy into the intervention group or control group. During maternity leave, supervisors in the intervention group contact their employee six weeks after delivery using a structured interview. When employees do not expect to return to their jobs at the end of their scheduled maternity leave due to health problems, the supervisor offers early support of the occupational physician. Supervisors in the control group have no structural contact with their employees during maternity leave. Measurements take place at 30 weeks pregnancy and at 6, 12, 24 and 52 weeks postpartum. In addition, cost data are collected. For the RCT, primary outcome measures are sick leave and return-to-work, and secondary outcome measures are costs, health, satisfaction with intervention and global feelings of recovery. Outcome measures for the cohort are pregnancy-related pelvic girdle pain, fatigue and depression. Finally, a number of prognostic factors for return-to-work and for the

75 FR 51816 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2010-08-23

... Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a... Special Exposure Cohort (SEC) under the Energy Employees Occupational Illness Compensation Program Act of...

Population-based imaging and radiomics. Rational and perspective of the German National Cohort MRI study

International Nuclear Information System (INIS)

Schlett, C.L.; Weckbach, S.; Hendel, T.

2016-01-01

The MRI study within the German National Cohort, a large-scale, population-based, longitudinal study in Germany, comprises comprehensive characterization and phenotyping of a total of 30 000 participants using 3-Tesla whole-body MR imaging. A multi-centric study design was established together with dedicated core facilities for e.g. managing incidental findings or providing quality assurance. As such, the study represents a unique opportunity to substantially impact imaging-based risk stratification leading to personalized and precision medicine. Supported by the developments in the field of computational science, the newly developing scientific field of radiomics has large potential for the future. In the present article we provide an overview on population-based imaging and Radiomics and conceptualize the rationale and design of the MRI study within the German National Cohort.

Functional health status in subjects after a motor vehicle accident, with emphasis on whiplash associated disorders: design of a descriptive, prospective inception cohort study

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Helders Paul JM

2008-12-01

Full Text Available Abstract Background The clinical consequences of whiplash injuries resulting from a motor vehicle accident (MVA are poorly understood. Thereby, there is general lack of research on the development of disability in patients with acute and chronic Whiplash Associated Disorders. Methods/Design The objective is to describe the design of an inception cohort study with a 1-year follow-up to determine risk factors for the development of symptoms after a low-impact motor vehicle accident, the prognosis of chronic disability, and costs. Victims of a low-impact motor vehicle accident will be eligible for participation. Participants with a Neck Disability Index (NDI score of 7 or more will be classified as experiencing post-traumatic neck pain and will enter the experimental group. Participants without complaints (a NDI score less than 7 will enter the reference group. The cohort will be followed up by means of postal questionnaires and physical examinations at baseline, 3 months, 6 months, and 12 months. Recovery from whiplash-associated disorders will be measured in terms of perceived functional health, and employment status (return to work. Life tables will be generated to determine the 1-year prognosis of whiplash-associated disorders, and risk factors and prognostic factors will be assessed using multiple logistic regression analysis. Discussion Little is known about the development of symptoms and chronic disability after a whiplash injury. In the clinical setting, it is important to identify those people who are at risk of developing chronic symptoms. This inception prospective cohort study will provide insight in the influence of risk factors, of the development of functional health problems, and costs in people with whiplash-associated disorders.

Functional health status in subjects after a motor vehicle accident, with emphasis on whiplash associated disorders: design of a descriptive, prospective inception cohort study

Science.gov (United States)

Schmitt, Maarten A; van Meeteren, Nico LU; de Wijer, Anton; Helders, Paul JM; Graaf, Yolanda van der

2008-01-01

Background The clinical consequences of whiplash injuries resulting from a motor vehicle accident (MVA) are poorly understood. Thereby, there is general lack of research on the development of disability in patients with acute and chronic Whiplash Associated Disorders. Methods/Design The objective is to describe the design of an inception cohort study with a 1-year follow-up to determine risk factors for the development of symptoms after a low-impact motor vehicle accident, the prognosis of chronic disability, and costs. Victims of a low-impact motor vehicle accident will be eligible for participation. Participants with a Neck Disability Index (NDI) score of 7 or more will be classified as experiencing post-traumatic neck pain and will enter the experimental group. Participants without complaints (a NDI score less than 7) will enter the reference group. The cohort will be followed up by means of postal questionnaires and physical examinations at baseline, 3 months, 6 months, and 12 months. Recovery from whiplash-associated disorders will be measured in terms of perceived functional health, and employment status (return to work). Life tables will be generated to determine the 1-year prognosis of whiplash-associated disorders, and risk factors and prognostic factors will be assessed using multiple logistic regression analysis. Discussion Little is known about the development of symptoms and chronic disability after a whiplash injury. In the clinical setting, it is important to identify those people who are at risk of developing chronic symptoms. This inception prospective cohort study will provide insight in the influence of risk factors, of the development of functional health problems, and costs in people with whiplash-associated disorders. PMID:19099574

Ethanol, Neurodevelopment, Infant and Child Health (ENRICH prospective cohort: Study design considerations

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Ludmila N. Bakhireva

2015-04-01

Full Text Available Background: While intervention is the leading factor in reducing long-term disabilities in children with fetal alcohol spectrum disorder (FASD, early identification of children affected by prenatal alcohol exposure (PAE remains challenging. Deficits in higher-order cognitive domains (e.g. executive function might be more specific to FASD than global neurodevelopmental tests, yet these functions are not developed in very young children. Measures of early sensorimotor development may provide early indications of atypical brain development during the first two years of life. Methods: This paper describes the novel methodology of the Ethanol, Neurodevelopment, Infant and Child Health (ENRICH prospective cohort study of 120 maternal-infant pairs with a goal to identify early indices of functional brain impairment associated with PAE. The cohort is established by recruiting women early in pregnancy and classifying them into one of three study groups: patients on opioid-maintenance therapy who consume alcohol during pregnancy (Group 1, patients on opioid-maintenance therapy who abstain from alcohol during pregnancy (Group 2, and healthy controls (Group 3. After the initial prenatal assessment (Visit 1, patients are followed to Visit 2 occurring at delivery, and two comprehensive assessments of children at six (Visit 3 and 20 months (Visit 4 of age. ENRICH recruitment started in November 2013 and 87 women were recruited during the first year. During Year 1, the biospecimen (maternal whole blood, serum, urine, dry blood spots of a newborn collection rate was 100% at Visit 1, and 97.6% for those who completed Visit 2. Discussion: The tiered screening approach, evaluation of confounders, neurocognitive and magneto-/electro-encephalography (MEG/EEG outcomes, and ethical considerations are discussed.

Commentary: considerations for using the 'Trials within Cohorts' design in a clinical trial of an investigational medicinal product.

Science.gov (United States)

Bibby, Anna C; Torgerson, David J; Leach, Samantha; Lewis-White, Helen; Maskell, Nick A

2018-01-08

The 'trials within cohorts' (TwiC) design is a pragmatic approach to randomised trials in which trial participants are randomly selected from an existing cohort. The design has multiple potential benefits, including the option of conducting multiple trials within the same cohort. To date, the TwiC design methodology been used in numerous clinical settings but has never been applied to a clinical trial of an investigational medicinal product (CTIMP). We have recently secured the necessary approvals to undertake the first CTIMP using the TwiC design. In this paper, we describe some of the considerations and modifications required to ensure such a trial is compliant with Good Clinical Practice and international clinical trials regulations. We advocate using a two-stage consent process and using the consent stages to explicitly differentiate between trial participants and cohort participants who are providing control data. This distinction ensured compliance but had consequences with respect to costings, recruitment and the trial assessment schedule. We have demonstrated that it is possible to secure ethical and regulatory approval for a CTIMP TwiC. By including certain considerations at the trial design stage, we believe this pragmatic and efficient methodology could be utilised in other CTIMPs in future.

The effect of urinary incontinence status during pregnancy and delivery mode on incontinence postpartum. A cohort study

OpenAIRE

Wesnes, Stian Langeland; Hunskår, Steinar; Bø, Kari; Rørtveit, Guri

2009-01-01

Objective: The objectives of this study were to investigate prevalence of urinary incontinence at 6 months postpartum and to study how continence status during pregnancy and mode of delivery influence urinary incontinence at 6 months postpartum in primiparous women.Design: Cohort study.Setting: Pregnant women attending routine ultrasound examination were recruited to the Norwegian Mother and Child Cohort Study (MoBa).Population A total of 12 679 primigravidas who were contin...

Differences in kinetic variables between injured and noninjured novice runners : A prospective cohort study

NARCIS (Netherlands)

Bredeweg, Steef W.; Kluitenberg, Bas; Bessem, Bram; Buist, Ida

Objectives: This prospective study examined differences in kinetic variables between injured and noninjured novice female and male runners and their potential contribution to RRIs. Design: A prospective cohort study. Methods: At baseline vertical ground reaction forces were assessed with an

Socioeconomic status and stomach cancer incidence in men: Results from the Netherlands Cohort Study

NARCIS (Netherlands)

Loon, A.J.M. van; Goldbohm, R.A.; Brandt, P.A. van den

1998-01-01

Study objective - To study the association between socioeconomic status (SES) and stomach cancer incidence (cardia and non-cardia) and the role of lifestyle factors in explaining this association. Design - Prospective cohort study on diet and cancer that started in 1986. Data were collected by means

Global teaching and training initiatives for emerging cohort studies

Directory of Open Access Journals (Sweden)

Jessica K. Paulus

2012-09-01

Full Text Available A striking disparity exists across the globe, with essentially no large-scale longitudinal studies ongoing in regions that will be significantly affected by the oncoming non-communicable disease epidemic. The successful implementation of cohort studies in most low-resource research environments presents unique challenges that may be aided by coordinated training programs. Leaders of emerging cohort studies attending the First World Cohort Integration Workshop were surveyed about training priorities, unmet needs and potential cross-cohort solutions to these barriers through an electronic pre-workshop questionnaire and focus groups. Cohort studies representing India, Mexico, Nigeria, South Africa, Sweden, Tanzania and Uganda described similar training needs, including on-the-job training, data analysis software instruction, and database and bio-bank management. A lack of funding and protected time for training activities were commonly identified constraints. Proposed solutions include a collaborative cross-cohort teaching platform with web-based content and interactive teaching methods for a range of research personnel. An international network for research mentorship and idea exchange, and modifying the graduate thesis structure were also identified as key initiatives. Cross-cohort integrated educational initiatives will efficiently meet shared needs, catalyze the development of emerging cohorts, speed closure of the global disparity in cohort research, and may fortify scientific capacity development in low-resource settings.

Milk intake and risk of mortality and fractures in women and men : cohort studies

OpenAIRE

Michaëlsson, Karl; Wolk, Alicja; Langenskiöld, Sophie; Basu, Samar; Warensjö Lemming, Eva; Melhus, Håkan; Byberg, Liisa

2014-01-01

OBJECTIVE: To examine whether high milk consumption is associated with mortality and fractures in women and men. DESIGN: Cohort studies. SETTING: Three counties in central Sweden. PARTICIPANTS: Two large Swedish cohorts, one with 61 433 women (39-74 years at baseline 1987-90) and one with 45 339 men (45-79 years at baseline 1997), were administered food frequency questionnaires. The women responded to a second food frequency questionnaire in 1997. MAIN OUTCOME MEASURE: Multivariable survival ...

Injuries in Professional Male Soccer Players in the Netherlands: A Prospective Cohort Study

NARCIS (Netherlands)

Stubbe, J.H.; van Beijsterveldt, A.M.M.C.; van der Knaap, S.; Stege, J.; Verhagen, E.A.L.M.; van Mechelen, W.; Backx, F.J.G.

2015-01-01

Context: Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective: To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design: Cohort study.

An inventory of Canadian pregnancy and birth cohort studies: research in progress

Directory of Open Access Journals (Sweden)

Joly Marie-Pier

2012-10-01

Full Text Available Abstract Background A web-based inventory was developed as a voluntary registry of Canadian pregnancy and birth cohort studies, with the objective to foster collaboration and sharing of research tools among cohort study groups as a means to enrich research in maternal and child health across Canada. Description Information on existing birth cohort studies conducted in Canada exclusively or as part of broader international initiatives was accessed by searching the literature in PubMed and PsychInfo databases. Additional studies were identified by enquiring about the research activities of researchers at Canadian universities or working in affiliated hospitals or research centres or institutes. Of the fifty-eight birth cohort studies initially identified, forty-six were incorporated into the inventory if they were of a retrospective and/or prospective longitudinal design and with a minimum of two phases of data collection, with the first period having occurred before, during, or shortly after pregnancy and had an initial study sample size of a minimum of 200 participants. Information collected from each study was organized into four main categories: basic information, data source and period of collection, exposures, and outcome measures and was coded and entered into an Excel spreadsheet. The information incorporated into the Excel spreadsheet was double checked, completed when necessary, and verified for completeness and accuracy by contacting the principal investigator or research coordinator. All data collected were then uploaded onto the website of the Institute of Human Development Child and Youth Health of the Canadian Institutes of Health Research. Subsequently, the database was updated and developed as an online searchable inventory on the website of the Maternal, Infant, Child and Youth Research Network. Conclusions This inventory is unique, as it represents detailed information assembled for the first time on a large number of Canadian

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.

Dietary pattern and 20 year mortality in elderly men in Finland, Italy and the Netherlands: Longitudinal cohort study.

NARCIS (Netherlands)

Huijbregts, P.; Feskens, E.J.M.; Résénen, L.; Fidanza, F.; Nissinen, A.; Menotti, A.; Kromhout, D.

1997-01-01

OBJECTIVE: To investigate the association of dietary pattern and mortality in international data. DESIGN: Cohort study with 20 years' follow up of mortality. SETTING: Five cohorts in Finland, the Netherlands, and Italy. SUBJECTS: Population based random sample of 3045 men aged 50-70 years in 1970.

The Carriage Of Multiresistant Bacteria After Travel (COMBAT) prospective cohort study: methodology and design.

Science.gov (United States)

Arcilla, Maris S; van Hattem, Jarne M; Bootsma, Martin C J; van Genderen, Perry J; Goorhuis, Abraham; Schultsz, Constance; Stobberingh, Ellen E; Verbrugh, Henri A; de Jong, Menno D; Melles, Damian C; Penders, John

2014-04-28

Antimicrobial resistance (AMR) is one of the major threats to public health around the world. Besides the intense use and misuse of antimicrobial agents as the major force behind the increase in antimicrobial resistance, the exponential increase of international travel may also substantially contribute to the emergence and spread of AMR. However, knowledge on the extent to which international travel contributes to this is still limited. The Carriage Of Multiresistant Bacteria After Travel (COMBAT) study aims to 1. determine the acquisition rate of multiresistant Enterobacteriaceae during foreign travel 2. ascertain the duration of carriage of these micro-organisms 3. determine the transmission rate within households 4. identify risk factors for acquisition, persistence of carriage and transmission of multiresistant Enterobacteriaceae. The COMBAT-study is a large-scale multicenter longitudinal cohort study among travellers (n = 2001) and their non-travelling household members (n = 215). Faecal samples are collected before and immediately after travel and 1 month after return from all participants. Follow-up faecal samples are collected 3, 6 and 12 months after return from travellers (and their non-travelling household members) who acquired multiresistant Enterobacteriaceae. Questionnaires are collected from all participants at each time-point. Faecal samples are screened phenotypically for the presence of extended-spectrum beta-lactamase (ESBL) or carbapenemase-producing Enterobacteriaceae. Positive post-travel isolates from travellers with negative pre-travel samples are genotypically analysed for ESBL and carbapenemase genes with microarray and gene sequencing. The design and scale of the COMBAT-study will enable us to provide much needed detailed insights into the risks and dynamics of introduction and spread of ESBL- and carbapenemase-producing Enterobacteriaceae by healthy travellers and the potential need and measures to monitor or manage these risks

What's in a Name? The Incorrect Use of Case Series as a Study Design Label in Studies Involving Dogs and Cats.

Science.gov (United States)

Sargeant, J M; O'Connor, A M; Cullen, J N; Makielski, K M; Jones-Bitton, A

2017-07-01

Study design labels are used to identify relevant literature to address specific clinical and research questions and to aid in evaluating the evidentiary value of research. Evidence from the human healthcare literature indicates that the label "case series" may be used inconsistently and inappropriately. Our primary objective was to determine the proportion of studies in the canine and feline veterinary literature labeled as case series that actually corresponded to descriptive cohort studies, population-based cohort studies, or other study designs. Our secondary objective was to identify the proportion of case series in which potentially inappropriate inferential statements were made. Descriptive evaluation of published literature. One-hundred published studies (from 19 journals) labeled as case series. Studies were identified by a structured literature search, with random selection of 100 studies from the relevant citations. Two reviewers independently characterized each study, with disagreements resolved by consensus. Of the 100 studies, 16 were case series. The remaining studies were descriptive cohort studies (35), population-based cohort studies (36), or other observational or experimental study designs (13). Almost half (48.8%) of the case series or descriptive cohort studies, with no control group and no formal statistical analysis, included inferential statements about the efficacy of treatment or statistical significance of potential risk factors. Authors, peer-reviewers, and editors should carefully consider the design elements of a study to accurately identify and label the study design. Doing so will facilitate an understanding of the evidentiary value of the results. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Use of fertility drugs and risk of ovarian cancer: Danish population based cohort study

OpenAIRE

Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten; Kj?r, Susanne Kr?ger

2009-01-01

Objective To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. Design Population based cohort study. Setting Danish hospitals and private fertility clinics. Participants 54?362 women with infertility problems referred to all Danish fertility clinics during 1963-98. The median age at first evaluation of infertility was 30 years (range 16-55 years), and the median age at the end of follow-up was 47 (range 18-81) years. In...

Risk of respiratory morbidity in term infants delivered by elective caesarean section: cohort study

DEFF Research Database (Denmark)

Hansen, Anne Kirkeby; Wisborg, Kirsten; Uldbjerg, Niels

2007-01-01

OBJECTIVE: To investigate the association between elective caesarean sections and neonatal respiratory morbidity and the importance of timing of elective caesarean sections. DESIGN: Cohort study with prospectively collected data from the Aarhus birth cohort, Denmark. SETTING: Obstetric department...... and neonatal department of a university hospital in Denmark. PARTICIPANTS: All liveborn babies without malformations, with gestational ages between 37 and 41 weeks, and delivered between 1 January 1998 and 31 December 2006 (34 458 babies). MAIN OUTCOME MEASURES: Respiratory morbidity (transitory tachypnoea...

The LifeLines Cohort Study : Prevalence and treatment of cardiovascular disease and risk factors

NARCIS (Netherlands)

van der Ende, M. Yldau; Hartman, Minke H. T.; Hagemeijer, Yanick; Meems, Laura M. G.; de Vries, Hendrik Sierd; Stolk, Ronald P.; de Boer, Rudolf A.; Sijtsma, Anna; van der Meer, Peter; Rienstra, Michiel; van der Harst, Pim

2017-01-01

Background: The LifeLines Cohort Study is a large three-generation prospective study and Biobank. Recruitment and data collection started in 2006 and follow-up is planned for 30 years. The central aim of LifeLines is to understand healthy ageing in the 21st century. Here, the study design, methods,

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

Chronic comorbidities in children with type 1 diabetes : a population-based cohort study

NARCIS (Netherlands)

Fazelifarsani, Soulmaz; Souverein, Patrick C|info:eu-repo/dai/nl/243074948; van der Vorst, Marja M J; Knibbe, Catherijne A J; de Boer, Anthonius|info:eu-repo/dai/nl/075097346; Mantel-Teeuwisse, Aukje K|info:eu-repo/dai/nl/266775098

OBJECTIVE: To determine the incidence of chronic comorbidities among children with type 1 diabetes (T1D) and to compare incidences with a group of children without diabetes. DESIGN: Population-based cohort study. SETTING: Dutch PHARMO database (1998-2010). PATIENTS: All patients (<19 years old) with

Mode of delivery affected questionnaire response rates in a birth cohort study

OpenAIRE

Bray, I.; Noble, S.; Robinson, R.; Molloy, L.; Tilling, K.

2017-01-01

Objectives Cohort studies must collect data from their participants as economically as possible, while maintaining response rates. This randomized controlled trial investigated whether offering a choice of online or paper questionnaires resulted in improved response rates compared with offering online first. Study Design and Setting Eligible participants were young people in the Avon Longitudinal Study of Parents and Children (ALSPAC) study (born April 1, 1991, to December 31, 1992, in the Av...

Case series and descriptive cohort studies in neurosurgery: the confusion and solution.

Science.gov (United States)

Esene, Ignatius N; Ngu, Julius; El Zoghby, Mohamed; Solaroglu, Ihsan; Sikod, Anna M; Kotb, Ali; Dechambenoit, Gilbert; El Husseiny, Hossam

2014-08-01

Case series (CS) are well-known designs in contemporary use in neurosurgery but are sometimes used in contexts that are incompatible with their true meaning as defined by epidemiologists. This inconsistent, inappropriate and incorrect use, and mislabeling impairs the appropriate indexing and sorting of evidence. Using PubMed, we systematically identified published articles that had "case series" in the "title" in 15 top-ranked neurosurgical journals from January 2008 to December 2012. The abstracts and/or full articles were scanned to identify those with descriptions of the principal method as being "case series" and then classified as "true case series" or "non-case series" by two independent investigators with 100 % inter-rater agreement. Sixty-four articles had the label "case series" in their "titles." Based on the definition of "case series" and our appraisal of the articles using Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines, 18 articles (28.13 %) were true case series, while 46 (71.87 %) were mislabeled. Thirty-five articles (54.69 %) mistook retrospective (descriptive) cohorts for CS. CS are descriptive with an outcome-based sampling, while "descriptive cohorts" have an exposure-based sampling of patients, followed over time to assess outcome(s). A comparison group is not a defining feature of a cohort study and distinguishes descriptive from analytic cohorts. A distinction between a case report, case series, and descriptive cohorts is absolutely necessary to enable the appropriate indexing, sorting, and application of evidence. Researchers need better training in methods and terminology, and editors and reviewers should scrutinize more carefully manuscripts claiming to be "case series" studies.

Program specific admission testing and dropout for sports science students: a prospective cohort study

DEFF Research Database (Denmark)

O'Neill, Lotte; Christensen, Mette Krogh; Vonsild, Maria Cecilie

2014-01-01

if admission strategy was also independently associated with dropout for sports science students in a university setting. The study design was a prospective cohort study with a 2 year follow-up. The population was 449 sports science students admitted to a university in the years 2002-2007. The analysis...

Opium use and mortality in Golestan Cohort Study: prospective cohort study of 50 000 adults in Iran

Science.gov (United States)

Khademi, Hooman; Pourshams, Akram; Jafari, Elham; Salahi, Rasool; Semnani, Shahryar; Abaie, Behrooz; Islami, Farhad; Nasseri-Moghaddam, Siavosh; Etemadi, Arash; Byrnes, Graham; Abnet, Christian C; Dawsey, Sanford M; Day, Nicholas E; Pharoah, Paul D; Boffetta, Paolo; Kamangar, Farin

2012-01-01

Objectives To investigate the association between opium use and subsequent risk of death. Design Prospective cohort study. Setting The Golestan Cohort Study in north-eastern Iran collected detailed validated data on opium use and other exposures at baseline. Participants were enrolled between January 2004 and June 2008 and were followed to May 2011, with a follow-up success rate of over 99%. Participants 50 045 participants aged 40-75 at baseline. Main outcomes Mortality, all cause and major subcategories. Results 17% (n=8487) of the participants reported opium use, with a mean duration of 12.7 years. During the follow-up period 2145 deaths were reported. The adjusted hazard ratio for all cause mortality associated with ever use of opium was 1.86 (95% confidence interval 1.68 to 2.06). Opium consumption was significantly associated with increased risks of deaths from several causes including circulatory diseases (hazard ratio 1.81) and cancer (1.61). The strongest associations were seen with deaths from asthma, tuberculosis, and chronic obstructive pulmonary disease (11.0, 6.22, and 5.44, respectively). After exclusion of people who self prescribed opium after the onset of major chronic illnesses, the associations remained strong with a dose-response relation. Conclusion Opium users have an increased risk of death from multiple causes compared with non-users. Increased risks were also seen in people who used low amounts of opium for a long period and those who had no major illness before use. PMID:22511302

Cohort profile: LIFEWORK, a prospective cohort study on occupational and environmental risk factors and health in the Netherlands.

Science.gov (United States)

Reedijk, Marije; Lenters, Virissa; Slottje, Pauline; Pijpe, Anouk; Peeters, Petra H; Korevaar, Joke C; Bueno-de-Mesquita, Bas; Verschuren, W M Monique; Verheij, Robert A; Pieterson, Inka; van Leeuwen, Flora E; Rookus, Matti A; Kromhout, Hans; Vermeulen, Roel C H

2018-02-03

LIFEWORK is a large federated prospective cohort established in the Netherlands to quantify the health effects of occupational and environmental exposures. This cohort is also the Dutch contribution to the international Cohort Study of Mobile Phone Use and Health (COSMOS). In this paper, we describe the study design, ongoing data collection, baseline characteristics of participants and the repeatability of key questionnaire items. 88 466 participants were enrolled in three cohort studies in 2011-2012. Exposure information was collected by a harmonised core questionnaire, or modelled based on occupational and residential histories; domains include air pollution (eg, nitrogen dioxide (NO 2 ), particulate matter with diameter ≤2.5 µm (PM 2.5 )), noise, electromagnetic fields (EMF), mobile phone use, shift work and occupational chemical exposures. Chronic and subacute health outcomes are assessed by self-report and through linkage with health registries. Participants had a median age of 51 years at baseline (range 19-87), and the majority are female (90%), with nurses being over-represented. Median exposure levels of NO 2 , PM 2.5 , EMF from base stations and noise at the participants' home addresses at baseline were 22.9 µg/m 3 , 16.6 µg/m 3 , 0.003 mWm 2 and 53.1 dB, respectively. Twenty-two per cent of participants reported to have started using a mobile phone more than 10 years prior to baseline. Repeatability for self-reported exposures was moderate to high (weighted kappa range: 0.69-1) for a subset of participants (n=237) who completed the questionnaire twice. We are actively and passively observing participants; we plan to administer a follow-up questionnaire every 4-5 years-the first follow-up will be completed in 2018-and linkage to cause-of-death and cancer registries occurs on a (bi)annual basis. This prospective cohort offers a unique, large and rich resource for research on contemporary occupational and environmental health risks and will

Cohort profile: cerebral palsy in the Norwegian and Danish birth cohorts (MOBAND-CP)

Science.gov (United States)

Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg; Petersen, Tanja Gram; Moster, Dag; Andersen, Anne-Marie Nybo; Stoltenberg, Camilla; Olsen, Jørn; Wilcox, Allen J

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 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 investigating various hypotheses regarding CP aetiology are currently on-going. Future plans Additional data can be harmonised as necessary to meet requirements of new projects. Biological specimens collected during pregnancy and at delivery are potentially available for assay, as are results from assays conducted on these specimens for other projects. The study size allows consideration of CP subtypes, which is rare in aetiological studies of CP. In addition, MOBAND-CP provides a platform within the context of a merged birth cohort of exceptional size that could, after appropriate permissions have been sought, be used for cohort and case-cohort studies of other relatively rare health conditions of infants and children. PMID:27591025

Cohort profile

DEFF Research Database (Denmark)

Kreiberg, Michael; Bandak, Mikkel; Lauritsen, Jakob

2018-01-01

The cohort was set up in order to analyze late effects in long-term testicular cancer survivors (TCS) and to contribute to the design of future follow-up programs addressing and potentially preventing late effects. Data for this cross-sectional study were collected between January 1, 2014, and De...

A nationwide registry-based cohort study of incidence of tonsillectomy in Denmark, 1991-2012

DEFF Research Database (Denmark)

Juul, Marie Louise; Rasmussen, Eva Rye; Rasmussen, Stig Hebbelstrup Rye

2018-01-01

OBJECTIVE: To update tonsillectomy incidence rates in Denmark and identify whether the incidence rates vary between geographical areas in the country during the period 1991-2012. DESIGN: This was a retrospective nationwide cohort study using data from the comprehensive Danish patient registries. ...

Cohort profile: The Limache, Chile, birth cohort study.

Science.gov (United States)

Amigo, Hugo; Bustos, Patricia; Zumelzú, Elinor; Rona, Roberto J

2014-08-01

The Limache cohort was set up to assess the programming and life course events hypotheses in relation to cardiovascular risk factors and chronic respiratory conditions, especially asthma, in the context of an unprecedented economic growth in Chile. The cohort was a representative sample of 1232 participants born between 1974 and 1978 in the hospital of Limache. The study includes data collected at birth, during the 1st year of life, at 22 to 28 years (collected between 2000 and 2002) and at 32 to 38 years (collected between 2010 and 2012). The data collected include anthropometric measurements at birth, 1st year of life and in adulthood, socio-economic and demographic data, lifestyle information including smoking, alcohol consumption and food intake, respiratory symptoms, lung function, broncho-reactivity to methacholine and skin prick reaction to eight allergens, measurement of cardiovascular risk factors and information on common mental health, mainly in the most recent study. The principal researchers welcome collaborative projects, especially those that will compare similar data sets in other settings. Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

Residential radon and lung cancer: a cohort study in Galicia, Spain

Directory of Open Access Journals (Sweden)

Raquel Barbosa-Lorenzo

Full Text Available Case-control studies show an association between residential radon and lung cancer. The aim of this paper is to investigate this association through a cohort study. We designed an ambispective cohort study using the Galician radon map, Spain, with controls drawn from a previous case-control study. Subjects were recruited between 2002 and 2009. The data were cross-checked to ascertain lung cancer incidence and then analysed using a Cox regression model. A total of 2,127 subjects participated; 24 lung cancer cases were identified; 76.6% of subjects were drawn from the radon map. The adjusted hazard ratio was 1.2 (95%CI: 0.5-2.8 for the category of subjects exposed to 50Bq/m3 or more. This risk rose when subjects from the case-control study were analyzed separately. In conclusion, we did not observe any statistically significant association between residential radon exposure and lung cancer; however, it appears that with a sample of greater median age (such as participants from the case-control study, the risk of lung cancer would have been higher.

Specialist Cohort Event Monitoring studies: a new study method for risk management in pharmacovigilance.

Science.gov (United States)

Layton, Deborah; Shakir, Saad A W

2015-02-01

The evolving regulatory landscape has heightened the need for innovative, proactive, efficient and more meaningful solutions for 'real-world' post-authorization safety studies (PASS) that not only align with risk management objectives to gather additional safety monitoring information or assess a pattern of drug utilization, but also satisfy key regulatory requirements for marketing authorization holder risk management planning and execution needs. There is a need for data capture across the primary care and secondary care interface, or for exploring use of new medicines in secondary care to support conducting PASS. To fulfil this need, event monitoring has evolved. The Specialist Cohort Event Monitoring (SCEM) study is a new application that enables a cohort of patients prescribed a medicine in the hospital and secondary care settings to be monitored. The method also permits the inclusion of a comparator cohort of patients receiving standard care, or another counterfactual comparator group, to be monitored concurrently, depending on the study question. The approach has been developed in parallel with the new legislative requirement for pharmaceutical companies to undertake a risk management plan as part of post-authorization safety monitoring. SCEM studies recognize that the study population comprises those patients who may have treatment initiated under the care of specialist health care professionals and who are more complex in terms of underlying disease, co-morbidities and concomitant medications than the general disease population treated in primary care. The aims of this paper are to discuss the SCEM new-user study design, rationale and features that aim to address possible bias (such as selection bias) and current applications.

Plant sterol intakes and colorectal cancer risk in the Netherlands : cohort study on diet and cancer

NARCIS (Netherlands)

Normén, A.L.; Brants, H.A.M.; Voorrips, L.E.; Andersson, H.A.; Brandt, P.A. van den

2001-01-01

Background: Plant sterols in vegetable foods might prevent colorectal cancer. Objective: The objective was to study plant sterol intakes in relation to colorectal cancer risk in an epidemiologic study. Design: The study was performed within the framework of the Netherlands Cohort Study on Diet and

Asymptomatic bacteriuria and urinary tract infection in pregnant women with and without diabetes : Cohort study

NARCIS (Netherlands)

Schneeberger, C.; Erwich, J.J.H.M.; van den Heuvel, E.R.; Mol, B.W.J.; Ott, A.; Geerlings, S.E.

2018-01-01

Objective: To compare the prevalence of asymptomatic bacteriuria (ASB) and the incidence of urinary tract infection (UTI) in pregnant women with and without diabetes mellitus (DM) or gestational DM (GDM). Study design: We performed a cohort study in five hospitals and two midwifery clinics in the

Studying variability in human brain aging in a population-based German cohort – Rationale and design of 1000BRAINS

Directory of Open Access Journals (Sweden)

Svenja eCaspers

2014-07-01

Full Text Available The ongoing 1000 brains study (1000BRAINS is an epidemiological and neuroscientific investigation of structural and functional variability in the human brain during aging. The two recruitment sources are the 10-year follow-up cohort of the German Heinz Nixdorf Recall (HNR Study, and the HNR MultiGeneration Study cohort, which comprises spouses and offspring of HNR subjects. The HNR is a longitudinal epidemiological investigation of cardiovascular risk factors, with a comprehensive collection of clinical, laboratory, socioeconomic, and environmental data from population-based subjects aged 45-75 years on inclusion. HNR subjects underwent detailed assessments in 2000, 2006, and 2011, and completed annual postal questionnaires on health status. 1000BRAINS accesses these HNR data and applies a separate protocol comprising: neuropsychological tests of attention, memory, executive functions & language; examination of motor skills; ratings of personality, life quality, mood & daily activities; analysis of laboratory and genetic data; and state-of-the-art magnetic resonance imaging (MRI, 3 Tesla of the brain. The latter includes (i 3D-T1- and 3D-T2-weighted scans for structural analyses and myelin mapping; (ii three diffusion imaging sequences optimized for diffusion tensor imaging, high-angular resolution diffusion imaging for detailed fibre tracking and for diffusion kurtosis imaging; (iii resting-state and task-based functional MRI; and (iv fluid-attenuated inversion recovery and MR angiography for the detection of vascular lesions and the mapping of white matter lesions. The unique design of 1000BRAINS allows: (i comprehensive investigation of various influences including genetics, environment and health status on variability in brain structure and function during aging; and (ii identification of the impact of selected influencing factors on specific cognitive subsystems and their anatomical correlates.

Public perceptions of cohort studies and biobanks in Germany.

Science.gov (United States)

Starkbaum, Johannes; Gottweis, Herbert; Gottweis, Ursula; Kleiser, Christina; Linseisen, Jakob; Meisinger, Christa; Kamtsiuris, Panagiotis; Moebus, Susanne; Jöckel, Karl-Heinz; Börm, Sonja; Wichmann, H-Erich

2014-04-01

Cohort studies and biobank projects have led to public discussions in several European countries in the past. In Germany, many medium-sized studies are currently running successfully in terms of respondent rates. However, EU-wide research on general public perceptions of biobanks and cohort studies have shown that Germany is among those countries where people express the highest reluctance for providing body material and other data for research purposes. Because of early efforts of the just-initiated German National Cohort Study, we are able to begin to investigate in greater detail how various groups of people across Germany reflect and discuss the ongoing implementation of cohort studies and biobanking in Germany. Our research is based on 15 focus group discussions in four German regions, as well as on Eurobarometer poll data on biobanking.

The Danish Alzheimer Intervention Study: Rationale, Study Design and Baseline Characteristics of the Cohort

DEFF Research Database (Denmark)

Waldemar, G.; Waldorff, F.B.; Buss, D.V.

2011-01-01

There is a lack of appropriately designed trials investigating the efficacy of psychosocial interventions for patients with mild dementia and their family caregivers. This paper reports the rationale and design of the Danish Alzheimer Disease Intervention Study and baseline characteristics...

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

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Kotaro Ozasa

2018-04-01

Full Text Available Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors' Offspring.

Science.gov (United States)

Ozasa, Kotaro; Grant, Eric J; Kodama, Kazunori

2018-04-05

Cohorts of atomic bomb survivors-including those exposed in utero-and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors' children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

Science.gov (United States)

Grant, Eric J; Kodama, Kazunori

2018-01-01

Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young. PMID:29553058

The epidemiology of multimorbidity in primary care: a retrospective cohort study.

OpenAIRE

Cassell, Anna; Edwards, Duncan Alexander; Harshfield, Amelia; Rhodes, Kirsty; Brimicombe, David; Payne, Rupert; Griffin, Simon James

2018-01-01

Background: Multimorbidity places a substantial burden on patients and the healthcare system but few contemporary data are available. Aim: To describe the epidemiology of multimorbidity in adults in England and quantify associations between multimorbidity and health service utilisation. Design: Retrospective cohort study Setting: A random sample of 403,985 adult patients (≥18 years) in England who were registered with a general practice on 1 January 2012 and included in the Clini...

Follow-up methods for retrospective cohort studies in New Zealand.

Science.gov (United States)

Fawcett, Jackie; Garrett, Nick; Bates, Michael N

2002-01-01

To define a general methodology for maximising the success of follow-up processes for retrospective cohort studies in New Zealand, and to illustrate an approach to developing country-specific follow-up methodologies. We recently conducted a cohort study of mortality and cancer incidence in New Zealand professional fire fighters. A number of methods were used to trace vital status, including matching with records of the New Zealand Health Information Service (NZHIS), pension records of Work and Income New Zealand (WINZ), and electronic electoral rolls. Non-electronic methods included use of paper electoral rolls and the records of the Registrar of Births Deaths and Marriages. 95% of the theoretical person-years of follow-up of the cohort were traced using these methods. In terms of numbers of cohort members traced to end of follow-up, the most useful tracing methods were fire fighter employment records, the NZHIS, WINZ, and the electronic electoral rolls. The follow-up process used for the cohort study was highly successful. On the basis of this experience, we propose a generic, but flexible, model for follow-up of retrospective cohort studies in New Zealand. Similar models could be constructed for other countries. Successful follow-up of cohort studies is possible in New Zealand using established methods. This should encourage the use of cohort studies for the investigation of epidemiological issues. Similar models for follow-up processes could be constructed for other countries.

Predictors for living at home after geriatric inpatient rehabilitation: A prospective cohort study.

OpenAIRE

Kool, Jan; Oesch, Peter; Bachmann, Stefan

2017-01-01

OBJECTIVE To evaluate patient characteristics predicting living at home after geriatric rehabilitation. DESIGN Prospective cohort study. PATIENTS A total of 210 patients aged 65 years or older receiving inpatient rehabilitation. METHODS Candidate predictors evaluated during rehabilitation were: age, vulnerability (Vulnerable Elders Survey), multimorbidity (Cumulative Illness Rating Scale), cognition (Mini-Mental State Examination), depression (Hospital Anxiety and ...

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.

Riyadh Mother and Baby Multicenter Cohort Study: The Cohort Profile.

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Hayfaa Wahabi

Full Text Available To assess the effects of non-communicable diseases, such as diabetes, hypertension and obesity, on the mother and the infant.A multicentre cohort study was conducted in three hospitals in the city of Riyadh in Saudi Arabia. All Saudi women and their babies who delivered in participating hospitals were eligible for recruitment. Data on socio-demographic characteristics in addition to the maternal and neonatal outcomes of pregnancy were collected. The cohort demographic profile was recorded and the prevalence of maternal conditions including gestational diabetes, pre-gestational diabetes, hypertensive disorders in pregnancy and obesity were estimated.The total number of women who delivered in participating hospitals during the study period was 16,012 of which 14,568 women participated in the study. The mean age of the participants was 29 ± 5.9 years and over 40% were university graduates. Most of the participants were housewives, 70% were high or middle income and 22% were exposed to secondhand smoke. Of the total cohort, 24% were married to a first cousin. More than 68% of the participants were either overweight or obese. The preterm delivery rate was 9%, while 1.5% of the deliveries were postdate. The stillbirth rate was 13/1000 live birth. The prevalence of gestational diabetes was 24% and that of pre-gestational diabetes was 4.3%. The preeclampsia prevalence was 1.1%. The labour induction rate was 15.5% and the cesarean section rate was 25%.Pregnant women in Saudi Arabia have a unique demographic profile. The prevalence of obesity and diabetes in pregnancy are among the highest in the world.

Assessment of Worldwide Acute Kidney injury Epidemiology in Neonates (AWAKEN: Design of a Retrospective Cohort Study

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Jennifer Garcia Jetton

2016-07-01

Full Text Available INTRODUCTION: Acute kidney injury (AKI affects ~30% of hospitalized neonates. Critical to advancing our understanding of neonatal AKI is collaborative research among neonatologists and nephrologists. The Neonatal Kidney Collaborative (NKC is an international, multidisciplinary group dedicated to investigating neonatal AKI. The AWAKEN study (Assessment of Worldwide Acute Kidney injury Epidemiology in Neonates was designed to describe the epidemiology of neonatal AKI, validate the definition of neonatal AKI, identify primary risk factors for neonatal AKI, and investigate the contribution of fluid management to AKI events and short term outcomes. METHODS and ANALYSIS: The NKC was established with at least one pediatric nephrologist and neonatologist from 24 institutions from 4 countries (USA, Canada, Australia, India. A Steering Committee and four subcommittees were created. The database subcommittee oversaw the development of the web-based database (MediData Rave™ that captured all NICU admissions from 1/1/14-3/31/14. Inclusion and exclusion criteria were applied to eliminate babies with a low likelihood of AKI. Data collection includes: 1 baseline demographic information; 2 daily physiologic parameters and care received during the first week of life; 3 weekly snapshots; 4 discharge information including growth parameters, final diagnoses, discharge medications and need for renal replacement therapy; and 5 all serum creatinine values. ETHICS and DISSEMINATION: AWAKEN was proposed as human subjects research. The study design allowed for a waiver of informed consent/parental permission. NKC investigators will disseminate data through peer-reviewed publications and educational conferences. DISCUSSION: The purpose of this publication is to describe the formation of the NKC, the establishment of the AWAKEN cohort and database, future directions and a few lessons learned. The AWAKEN database includes ~325 unique variables and >4 million discrete data

Use of fertility drugs and risk of ovarian cancer: Danish Population Based Cohort Study

DEFF Research Database (Denmark)

Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten

2009-01-01

OBJECTIVE: To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. DESIGN: Population based cohort study. SETTING: Danish hospitals and private fertility clinics. PARTICIPANTS: 54,362 women with infertility problems referred...... confounding factors. RESULTS: Analyses within cohort showed no overall increased risk of ovarian cancer after any use of gonadotrophins (rate ratio 0.83, 95% confidence interval 0.50 to 1.37), clomifene (1.14, 0.79 to 1.64), human chorionic gonadotrophin (0.89, 0.62 to 1.29), or gonadotrophin releasing...... hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity. CONCLUSION: No convincing association was found between use of fertility drugs and risk of ovarian cancer....

Cohort profile: LIFEWORK, a prospective cohort study on occupational and environmental risk factors and health in the Netherlands.

NARCIS (Netherlands)

Reedijk, M.; Lenters, V.; Slottje, P.; Pijpe, A.; Peeters, P.H.; Korevaar, J.C.; Bueno-de-Mesquita, B.; Verschuren, W.M.M.; Verheij, R.A.; Pieterson, I.; Leeuwen, F.E. van; Rookus, M.A.; Kromhout, H.; Vermeulen, R.C.H.

2017-01-01

Purpose LIFEWORK is a large federated prospective cohort established in the Netherlands to quantify the health effects of occupational and environmental exposures. This cohort is also the Dutch contribution to the international Cohort Study of Mobile Phone Use and Health (COSMOS). In this paper, we

Impact of organised mammography screening on breast cancer mortality in a case–control and cohort study

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Heinävaara, Sirpa; Sarkeala, Tytti; Anttila, Ahti

2016-01-01

Background: The usefulness of case–control studies has been questioned. Our aim was to evaluate the long-term effect of screening on breast cancer mortality within the population-based mammography programme in Finland using a case–control design, and to compare the analyses with the earlier cohort study. Methods: The cases were women invited to screening, diagnosed and died from breast cancer in 1992–2011 while being 50–84 years at death. We chose 10 controls for each case with non-restrictive eligibility criteria. Our data included 1907 cases and 18 978 matched controls. We analysed associations between the screening participation and the risk of breast cancer death using the conditional Cox proportional hazards model. The effect estimates were corrected for self-selection bias. Results: An overall effect of screening was 0.67 (95% confidence interval (CI): 0.49–0.90), and that remained unchanged over time. Analyses with matching criteria comparable to the cohort study yielded an effect (0.70, 95% CI: 0.49–1.00) in 1992–2003 similar to that of the previous cohort analysis (0.72, 95% CI: 0.56–0.88). Conclusions: Organised mammography screening decreases mortality from breast cancer by 33% among the participants. If made comparable, a case–cohort study can yield effect estimates similar to a cohort study. PMID:27010748

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

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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.

The WISTAH hand study: A prospective cohort study of distal upper extremity musculoskeletal disorders

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Garg Arun

2012-06-01

Full Text Available Abstract Background Few prospective cohort studies of distal upper extremity musculoskeletal disorders have been performed. Past studies have provided somewhat conflicting evidence for occupational risk factors and have largely reported data without adjustments for many personal and psychosocial factors. Methods/design A multi-center prospective cohort study was incepted to quantify risk factors for distal upper extremity musculoskeletal disorders and potentially develop improved methods for analyzing jobs. Disorders to analyze included carpal tunnel syndrome, lateral epicondylalgia, medial epicondylalgia, trigger digit, deQuervain’s stenosing tenosynovitis and other tendinoses. Workers have thus far been enrolled from 17 different employment settings in 3 diverse US states and performed widely varying work. At baseline, workers undergo laptop administered questionnaires, structured interviews, two standardized physical examinations and nerve conduction studies to ascertain demographic, medical history, psychosocial factors and current musculoskeletal disorders. All workers’ jobs are individually measured for physical factors and are videotaped. Workers are followed monthly for the development of musculoskeletal disorders. Repeat nerve conduction studies are performed for those with symptoms of tingling and numbness in the prior six months. Changes in jobs necessitate re-measure and re-videotaping of job physical factors. Case definitions have been established. Point prevalence of carpal tunnel syndrome is a combination of paraesthesias in at least two median nerve-served digits plus an abnormal nerve conduction study at baseline. The lifetime cumulative incidence of carpal tunnel syndrome will also include those with a past history of carpal tunnel syndrome. Incident cases will exclude those with either a past history or prevalent cases at baseline. Statistical methods planned include survival analyses and logistic regression. Discussion A

Risk and protective factors for meningococcal disease in adolescents: matched cohort study

OpenAIRE

Tully, Joanna; Viner, Russell M; Coen, Pietro G; Stuart, James M; Zambon, Maria; Peckham, Catherine; Booth, Clare; Klein, Nigel; Kaczmarski, Ed; Booy, Robert

2006-01-01

Objective: To examine biological and social risk factors for meningococcal disease in adolescents. Design: Prospective, population based, matched cohort study with controls matched for age and sex in 1:1 matching. Controls were sought from the general practitioner. Setting: Six contiguous regions of England, which represent some 65% of the country’s population. Participants: 15-19 year olds with meningococcal disease recruited at hospital admission in six regions (repr...

Design and rationale of the HCC BRIDGE study in China: a longitudinal, multicenter cohort trial in hepatocellular carcinoma

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Qiao You-Lin

2011-05-01

Full Text Available Abstract Background More than 50% of the worldwide cases of hepatocellular carcinoma occur in China, and this malignancy currently represents the country's second leading cause of cancer death in cities and the leading cause in rural areas. Despite recent advances in the control and management of hepatocellular carcinoma within China, this disease remains a major health care issue. The global HCC BRIDGE study, designed to assess patterns of hepatocellular carcinoma therapy use and associated outcomes across real-world clinical practice, has recently been expanded as a national study in China, allowing a detailed analysis of hepatocellular carcinoma in this important country. Methods/Design The global HCC BRIDGE study is a multiregional longitudinal cohort trial including patients newly diagnosed with hepatocellular carcinoma between January 1, 2005, and June 30, 2011, who are receiving treatment for hepatocellular carcinoma via sites in the Asia-Pacific, European, and North American regions. The HCC BRIDGE China national study comprises the portion of the global HCC BRIDGE study conducted within mainland China. Patients will be followed from time of diagnosis of hepatocellular carcinoma (post-January 1, 2005 to time of death or December 31, 2011, whichever comes first. Data will be collected on demographic/clinical characteristics, relevant laboratory values, hepatocellular carcinoma/underlying liver disease treatment, tumor response, adverse events, hospitalizations, and overall survival. The primary study end point is overall survival; secondary end points are disease progression, treatment-limiting adverse events, and treatment failure. Results At the time of writing, 15 sites have selected for participation across all 7 traditional regions of China (North, North-East, East, South, South-West, North-West, and Central. The anticipated study population from the China national study is approximately 9000 patients. Discussion Findings from the

Symptomatic venous thromboembolism in orthognathic surgery and distraction osteogenesis: a retrospective cohort study of 4127 patients

NARCIS (Netherlands)

Verlinden, C.R.A.; Tuinzing, D.B.; Forouzanfar, T.

2014-01-01

Venous thromboembolism is a common postoperative complication, and orthopaedic procedures are particularly at risk. We designed a retrospective, single centre, observational, cohort study of 4127 patients (mean (SD) age 27 (11) years) who had elective orthognathic operations or distraction

Development and validation of outcome prediction models for aneurysmal subarachnoid haemorrhage : The SAHIT multinational cohort study

NARCIS (Netherlands)

Jaja, Blessing N R; Saposnik, Gustavo; Lingsma, Hester F.; Macdonald, Erin; Thorpe, Kevin E.; Mamdani, Muhammed; Steyerberg, Ewout W.; Molyneux, Andrew; Manoel, Airton Leonardo De Oliveira; Schatlo, Bawarjan; Hanggi, Daniel; Hasan, David M.; Wong, George K C; Etminan, Nima; Fukuda, Hitoshi; Torner, James C.; Schaller, Karl L.; Suarez, Jose I.; Stienen, Martin N.; Vergouwen, Mervyn D.I.; Rinkel, Gabriel J.E.; Spears, Julian; Cusimano, Michael D.; Todd, Michael; Le Roux, Peter; Kirkpatrick, Peter J.; Pickard, John; Van Den Bergh, Walter M.; Murray, Gordon D; Johnston, S. Claiborne; Yamagata, Sen; Mayer, Stephan A.; Schweizer, Tom A.; Macdonald, R. Loch

2018-01-01

Objective To develop and validate a set of practical prediction tools that reliably estimate the outcome of subarachnoid haemorrhage from ruptured intracranial aneurysms (SAH). Design Cohort study with logistic regression analysis to combine predictors and treatment modality. Setting Subarachnoid

Soccer injuries and recovery in dutch male amateur soccer players: Results of a prospective cohort study

NARCIS (Netherlands)

Beijsterveldt, A.M. van; Steffen, K.; Stubbe, J.H.; Frederiks, J.E.; Port, I.G.L. van de; Backx, F.J.G.

2014-01-01

OBJECTIVE:: To describe characteristics of outdoor soccer injury and recovery among Dutch soccer players. DESIGN:: Prospective cohort study. SETTING:: The 2009-2010 competitive season (33 weeks). PARTICIPANTS:: Four hundred fifty-six Dutch male soccer players of 23 amateur teams. MAIN OUTCOME

Cancer incidence among 1st generation migrants compared to native Danes--a retrospective cohort study

DEFF Research Database (Denmark)

Nørredam, Marie Louise; Krasnik, A; Pipper, C

2007-01-01

STUDY AIMS: To investigate the incidence of cancer among 1st generation migrants compared to native Danes, including time trends in the risk of cancer among migrants. METHODS: A retrospective cohort study design. Migrants were matched 1:4 on age and sex with a Danish born reference population....... The time trends of the study are interesting and a relevant topic for further research....

Trends in the incidence of dementia: design and methods in the Alzheimer Cohorts Consortium.

Science.gov (United States)

Chibnik, Lori B; Wolters, Frank J; Bäckman, Kristoffer; Beiser, Alexa; Berr, Claudine; Bis, Joshua C; Boerwinkle, Eric; Bos, Daniel; Brayne, Carol; Dartigues, Jean-Francois; Darweesh, Sirwan K L; Debette, Stephanie; Davis-Plourde, Kendra L; Dufouil, Carole; Fornage, Myriam; Grasset, Leslie; Gudnason, Vilmundur; Hadjichrysanthou, Christoforos; Helmer, Catherine; Ikram, M Arfan; Ikram, M Kamran; Kern, Silke; Kuller, Lewis H; Launer, Lenore; Lopez, Oscar L; Matthews, Fiona; Meirelles, Osorio; Mosley, Thomas; Ower, Alison; Psaty, Bruce M; Satizabal, Claudia L; Seshadri, Sudha; Skoog, Ingmar; Stephan, Blossom C M; Tzourio, Christophe; Waziry, Reem; Wong, Mei Mei; Zettergren, Anna; Hofman, Albert

2017-10-01

Several studies have reported a decline in incidence of dementia which may have large implications for the projected burden of disease, and provide important guidance to preventive efforts. However, reports are conflicting or inconclusive with regard to the impact of gender and education with underlying causes of a presumed declining trend remaining largely unidentified. The Alzheimer Cohorts Consortium aggregates data from nine international population-based cohorts to determine changes in the incidence of dementia since 1990. We will employ Poisson regression models to calculate incidence rates in each cohort and Cox proportional hazard regression to compare 5-year cumulative hazards across study-specific epochs. Finally, we will meta-analyse changes per decade across cohorts, and repeat all analysis stratified by sex, education and APOE genotype. In all cohorts combined, there are data on almost 69,000 people at risk of dementia with the range of follow-up years between 2 and 27. The average age at baseline is similar across cohorts ranging between 72 and 77. Uniting a wide range of disease-specific and methodological expertise in research teams, the first analyses within the Alzheimer Cohorts Consortium are underway to tackle outstanding challenges in the assessment of time-trends in dementia occurrence.

The UAE healthy future study: a pilot for a prospective cohort study of 20,000 United Arab Emirates nationals.

Science.gov (United States)

Abdulle, Abdishakur; Alnaeemi, Abdullah; Aljunaibi, Abdullah; Al Ali, Abdulrahman; Al Saedi, Khaled; Al Zaabi, Eiman; Oumeziane, Naima; Al Bastaki, Marina; Al-Houqani, Mohammed; Al Maskari, Fatma; Al Dhaheri, Ayesha; Shah, Syed M; Loney, Tom; El-Sadig, Mohamed; Oulhaj, Abderrahim; Wareth, Leila Abdel; Al Mahmeed, Wael; Alsafar, Habiba; Hirsch, Benjamin; Al Anouti, Fatme; Yaaqoub, Jamila; Inman, Claire K; Al Hamiz, Aisha; Al Hosani, Ayesha; Haji, Muna; Alsharid, Teeb; Al Zaabi, Thekra; Al Maisary, Fatima; Galani, Divya; Sprosen, Tim; El Shahawy, Omar; Ahn, Jiyoung; Kirchhoff, Tomas; Ramasamy, Ravichandran; Schmidt, Ann Marie; Hayes, Richard; Sherman, Scott; Ali, Raghib

2018-01-05

The United Arab Emirates (UAE) is faced with a rapidly increasing burden of non-communicable diseases including obesity, diabetes, and cardiovascular disease. The UAE Healthy Future study is a prospective cohort designed to identify associations between risk factors and these diseases amongst Emiratis. The study will enroll 20,000 UAE nationals aged ≥18 years. Environmental and genetic risk factors will be characterized and participants will be followed for future disease events. As this was the first time a prospective cohort study was being planned in the UAE, a pilot study was conducted in 2015 with the primary aim of establishing the feasibility of conducting the study. Other objectives were to evaluate the implementation of the main study protocols, and to build adequate capacity to conduct advanced clinical laboratory analyses. Seven hundred sixty nine UAE nationals aged ≥18 years were invited to participate voluntarily in the pilot study. Participants signed an informed consent, completed a detailed questionnaire, provided random blood, urine, and mouthwash samples and were assessed for a series of clinical measures. All specimens were transported to the New York University Abu Dhabi laboratories where samples were processed and analyzed for routine chemistry and hematology. Plasma, serum, and a small whole blood sample for DNA extraction were aliquoted and stored at -80 °C for future analyses. Overall, 517 Emirati men and women agreed to participate (68% response rate). Of the total participants, 495 (95.0%), 430 (82.2%), and 492 (94.4%), completed the questionnaire, physical measurements, and provided biological samples, respectively. The pilot study demonstrated the feasibility of recruitment and completion of the study protocols for the first large-scale cohort study designed to identify emerging risk factors for the major non-communicable diseases in the region.

Challenges in translating end points from trials to observational cohort studies in oncology

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Ording AG

2016-06-01

Full Text Available Anne Gulbech Ording,1 Deirdre Cronin-Fenton,1 Vera Ehrenstein,1 Timothy L Lash,1,2 John Acquavella,1 Mikael Rørth,1 Henrik Toft Sørensen1 1Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark; 2Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA Abstract: Clinical trials are considered the gold standard for examining drug efficacy and for approval of new drugs. Medical databases and population surveillance registries are valuable resources for post-approval observational research, which are increasingly used in studies of benefits and risk of new cancer drugs. Here, we address the challenges in translating endpoints from oncology trials to observational studies. Registry-based cohort studies can investigate real-world safety issues – including previously unrecognized concerns – by examining rare endpoints or multiple endpoints at once. In contrast to clinical trials, observational cohort studies typically do not exclude real-world patients from clinical practice, such as old and frail patients with comorbidity. The observational cohort study complements the clinical trial by examining the effectiveness of interventions applied in clinical practice and by providing evidence on long-term clinical outcomes, which are often not feasible to study in a clinical trial. Various endpoints can be included in clinical trials, such as hard endpoints, soft endpoints, surrogate endpoints, and patient-reported endpoints. Each endpoint has it strengths and limitations for use in research studies. Endpoints used in oncology trials are often not applicable in observational cohort studies which are limited by the setting of standard clinical practice and by non-standardized endpoint determination. Observational studies can be more helpful moving research forward if they restrict focus to appropriate and valid endpoints. Keywords: endpoint determination, medical oncology

Rationale and design of South Asian Birth Cohort (START: a Canada-India collaborative study

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Anand Sonia S

2013-01-01

Full Text Available Abstract Background People who originate from the Indian subcontinent (South Asians suffer among the highest rates of type 2 diabetes in the world. Prior evidence suggests that metabolic risk factors develop early in life and are influenced by maternal and paternal behaviors, the intrauterine environment, and genetic factors. The South Asian Birth Cohort Study (START will investigate the environmental and genetic basis of adiposity among 750 South Asian offspring recruited from highly divergent environments, namely, rural and urban India and urban Canada. Methods Detailed information on health behaviors including diet and physical activity, and blood samples for metabolic parameters and DNA are collected from pregnant women of South Asian ancestry who are free of significant chronic disease. They also undergo a provocative test to diagnose impaired glucose tolerance and gestational diabetes. At delivery, cord blood and newborn anthropometric indices (i.e. birth weight, length, head circumference and skin fold thickness are collected. The mother and growing offspring are followed prospectively and information on the growth trajectory, adiposity and health behaviors will be collected annually up to age 3 years. Our aim is to recruit a minimum of 750 mother-infant pairs equally divided between three divergent environments: rural India, urban India, and Canada. Summary The START cohort will increase our understanding of the environmental and genetic determinants of adiposity and related metabolic abnormalities among South Asians living in India and Canada.

Research Data Explorer: Lessons Learned in Design and Development of Context-based Cohort Definition and Selection.

Science.gov (United States)

Wilcox, Adam; Vawdrey, David; Weng, Chunhua; Velez, Mark; Bakken, Suzanne

2015-01-01

Research Data eXplorer (RedX) was designed to support self-service research data queries and cohort identification from clinical research databases. The primary innovation of RedX was the electronic health record view of patient data, to provide better contextual understanding for non-technical users in building complex data queries. The design of RedX around this need identified multiple functions that would use individual patient views to better understand population-based data, and vice-versa. During development, the more necessary and valuable components of RedX were refined, leading to a functional self-service query and cohort identification tool. However, with the improved capabilities and extensibility of other applications for data querying and navigation, our long-term implementation and dissemination plans have moved towards consolidation and alignment of RedX functions as enhancements in these other initiatives.

Testicular cancer risk and maternal parity: a population-based cohort study.

Science.gov (United States)

Westergaard, T; Andersen, P K; Pedersen, J B; Frisch, M; Olsen, J H; Melbye, M

1998-04-01

The aim was to study, in a population-based cohort design, whether first-born sons run a higher risk of testicular cancer than later born sons; to investigate whether this difference in risk was affected by birth cohort, age of the son, maternal age, interval to previous delivery and other reproductive factors; and, finally, to evaluate to what extent changes in women's parity over time might explain the increasing incidence of testicular cancer. By using data from the Civil Registration System, a database was established of all women born in Denmark since 1935 and all their children alive in 1968 or born later. Sons with testicular cancer were identified in the Danish Cancer Registry. Among 1015994 sons followed for 15981 967 person-years, 626 developed testicular cancer (443 non-seminomas, 183 seminomas). Later born sons had a decreased risk of testicular cancer (RR = 0.80, 95% CI = 0.67-0.95) compared with first-born sons. The RR was 0.79 (95% CI = 0.64-0.98) for non-seminomas and 0.81 (95% CI = 0.58-1.13) for seminomas. There was no association between testicular cancer risk and overall parity of the mother, maternal or paternal age at the birth of the son, or maternal age at first birth. The decreased risk of testicular cancer among later born sons was not modified by age, birth cohort, interval to the previous birth, sex of the first-born child, or maternal age at birth of the son or at first birth. The increased proportion of first-borns from birth cohort 1946 to birth cohort 1969 only explained around 3% of an approximated two-fold increase in incidence between the cohorts. Our data document a distinctly higher risk of testicular cancer in first-born compared with later born sons and suggest that the most likely explanation should be sought among exposures in utero. The increase in the proportion of first-borns in the population has only contributed marginally to the increase in testicular cancer incidence.

Exploring generational cohort work satisfaction in hospital nurses.

Science.gov (United States)

Gordon, Pamela Ann

2017-07-03

Purpose Although extensive research exists regarding job satisfaction, many previous studies used a more restrictive, quantitative methodology. The purpose of this qualitative study is to capture the perceptions of hospital nurses within generational cohorts regarding their work satisfaction. Design/methodology/approach A preliminary qualitative, phenomenological study design explored hospital nurses' work satisfaction within generational cohorts - Baby Boomers (1946-1964), Generation X (1965-1980) and Millennials (1981-2000). A South Florida hospital provided the venue for the research. In all, 15 full-time staff nurses, segmented into generational cohorts, participated in personal interviews to determine themes related to seven established factors of work satisfaction: pay, autonomy, task requirements, administration, doctor-nurse relationship, interaction and professional status. Findings An analysis of the transcribed interviews confirmed the importance of the seven factors of job satisfaction. Similarities and differences between the generational cohorts related to a combination of stages of life and generational attributes. Practical implications The results of any qualitative research relate only to the specific venue studied and are not generalizable. However, the information gleaned from this study is transferable and other organizations are encouraged to conduct their own research and compare the results. Originality/value This study is unique, as the seven factors from an extensively used and highly respected quantitative research instrument were applied as the basis for this qualitative inquiry into generational cohort job satisfaction in a hospital setting.

Cohort Profile: The Danish Testicular Cancer Late Treatment Effects Cohort (DaTeCa-LATE

Directory of Open Access Journals (Sweden)

Michael Kreiberg

2018-02-01

Full Text Available The cohort was set up in order to analyze late effects in long-term testicular cancer survivors (TCS and to contribute to the design of future follow-up programs addressing and potentially preventing late effects. Data for this cross-sectional study were collected between January 1, 2014, and December 31, 2016, among living Danish TCS and 60% agreed to participate in the cohort (N = 2,572. Mean time since testicular cancer (TC diagnosis was 18 years (range 7–33 and mean age of participants was 53 years (range 25–95. Data consist of results of a questionnaire with patient reported outcomes which covers a broad range of items on late-effects. The study also included data obtained through linkages to Danish registries, a biobank, and clinical data from hospital files and pathology reports originating from the Danish Testicular Cancer Database (DaTeCa. The treatment during the observation period has been nearly the same for all stages of TC and is in agreement with today’s standard treatment, this allows for interesting analysis with a wide timespan. We have extensive data on non-responders and are able to validate our study findings. Data from a Danish reference population (N = 162,283 allow us to compare our findings with a Danish background population. The cohort can easily be extended to access more outcomes, or include new TCS. A limitation of the present study is the cross-sectional design and despite the large sample size, The Danish Testicular Cancer Late Treatment Effects Cohort (DaTeCa-LATE lacks statistical power to study very rare late effects. Since it was voluntary to participate in the study we have some selection bias, for instance, we lack responders who were not in a paired relationship, but we would still argue that this cohort of TCSs is representative for TCSs in Denmark.Collaboration and data accessResearches interested in collaboration with the DaTeCa-LATE study group please contact Professor Gedske Daugaard

Changes and determinants of life satisfaction after spinal cord injury : A cohort study in The Netherlands

NARCIS (Netherlands)

van Koppenhagen, Casper F.; Post, Marcel W.; van der Woude, Luc H.; de Witte, Luc P.; van Asbeck, Floris W.; de Groot, Sonja; van den Heuvel, Wim; Lindeman, Eline

Objective: To determine the impact of spinal cord injury (SCI) on life satisfaction of persons with SCI I year after discharge of inpatient rehabilitation. Design: A cohort. study. Life satisfaction before SCI was retrospectively measured at the start of active rehabilitation. One year after

Risk of lung cancer associated with domestic use of coal in Xuanwei, China: retrospective cohort study

NARCIS (Netherlands)

Barone-Adesi, F.; Chapman, R.S.; Silverman, D.T.; He, X.; Hu, W.; Vermeulen, R.; Ning, B.; Fraumeni, J.F.; Rothman, N.; Lan, Q.

2012-01-01

OBJECTIVE: To estimate the risk of lung cancer associated with the use of different types of coal for household cooking and heating. SETTING: Xuanwei County, Yunnan Province, China. DESIGN: Retrospective cohort study (follow-up 1976-96) comparing mortality from lung cancer between lifelong users of

The interaction of lexical semantics and cohort competition in spoken word recognition: an fMRI study.

Science.gov (United States)

Zhuang, Jie; Randall, Billi; Stamatakis, Emmanuel A; Marslen-Wilson, William D; Tyler, Lorraine K

2011-12-01

Spoken word recognition involves the activation of multiple word candidates on the basis of the initial speech input--the "cohort"--and selection among these competitors. Selection may be driven primarily by bottom-up acoustic-phonetic inputs or it may be modulated by other aspects of lexical representation, such as a word's meaning [Marslen-Wilson, W. D. Functional parallelism in spoken word-recognition. Cognition, 25, 71-102, 1987]. We examined these potential interactions in an fMRI study by presenting participants with words and pseudowords for lexical decision. In a factorial design, we manipulated (a) cohort competition (high/low competitive cohorts which vary the number of competing word candidates) and (b) the word's semantic properties (high/low imageability). A previous behavioral study [Tyler, L. K., Voice, J. K., & Moss, H. E. The interaction of meaning and sound in spoken word recognition. Psychonomic Bulletin & Review, 7, 320-326, 2000] showed that imageability facilitated word recognition but only for words in high competition cohorts. Here we found greater activity in the left inferior frontal gyrus (BA 45, 47) and the right inferior frontal gyrus (BA 47) with increased cohort competition, an imageability effect in the left posterior middle temporal gyrus/angular gyrus (BA 39), and a significant interaction between imageability and cohort competition in the left posterior superior temporal gyrus/middle temporal gyrus (BA 21, 22). In words with high competition cohorts, high imageability words generated stronger activity than low imageability words, indicating a facilitatory role of imageability in a highly competitive cohort context. For words in low competition cohorts, there was no effect of imageability. These results support the behavioral data in showing that selection processes do not rely solely on bottom-up acoustic-phonetic cues but rather that the semantic properties of candidate words facilitate discrimination between competitors.

A brief dietary assessment predicts executive dysfunction in an elderly cohort: results from the Einstein Aging Study

Science.gov (United States)

Objectives: To examine the association between diet and executive function, episodic memory and global verbal cognition in the Einstein Aging Study (EAS) cohort and determine whether race modifies this relationship. Design: Cross-sectional. Setting: Community. Participants: EAS participants without ...

Criminality in men with Klinefelter's syndrome and XYY syndrome: a cohort study

OpenAIRE

Stochholm, Kirstine; Bojesen, Anders; Jensen, Anne Skakkebæk; Juul, Svend; Gravholt, Claus Højbjerg

2012-01-01

Objective To investigate the criminal pattern in men between 15 and 70 years of age diagnosed with 47,XXY (Klinefelter's syndrome (KS)) or 47,XYY compared to the general population. Design Register-based cohort study comparing the incidence of convictions among men with KS and with 47,XYY with age- and calendar-matched samples of the general population. Crime was classified into eight types (sexual abuse, homicide, burglary, violence, traffic, drug-related, arson and ‘others’). Setting Denmar...

California Men's Health Study (CMHS: a multiethnic cohort in a managed care setting

Directory of Open Access Journals (Sweden)

Sadler Marianne C

2006-06-01

Full Text Available Abstract Background We established a male, multiethnic cohort primarily to study prostate cancer etiology and secondarily to study the etiologies of other cancer and non-cancer conditions. Methods/Design Eligible participants were 45-to-69 year old males who were members of a large, prepaid health plan in California. Participants completed two surveys on-line or on paper in 2002 – 2003. Survey content included demographics; family, medical, and cancer screening history; sexuality and sexual development; lifestyle (diet, physical activity, and smoking; prescription and non-prescription drugs; and herbal supplements. We linked study data with clinical data, including laboratory, hospitalization, and cancer data, from electronic health plan files. We recruited 84,170 participants, approximately 40% from minority populations and over 5,000 who identified themselves as other than heterosexual. We observed a wide range of education (53% completed less than college and income. PSA testing rates (75% overall were highest among black participants. Body mass index (BMI (median 27.2 was highest for blacks and Latinos and lowest for Asians, and showed 80.6% agreement with BMI from clinical data sources. The sensitivity and specificity can be assessed by comparing self-reported data, such as PSA testing, diabetes, and history of cancer, to health plan data. We anticipate that nearly 1,500 prostate cancer diagnoses will occur within five years of cohort inception. Discussion A wide variety of epidemiologic, health services, and outcomes research utilizing a rich array of electronic, biological, and clinical resources is possible within this multiethnic cohort. The California Men's Health Study and other cohorts nested within comprehensive health delivery systems can make important contributions in the area of men's health.

Maternal employment and early childhood overweight: findings from the UK Millennium Cohort Study

OpenAIRE

Hawkins, S. S.; Cole, T. J.; Law, C.; Millennium Cohort Study Child Health Group, The

2008-01-01

Background: In most developed countries, maternal employment has increased rapidly. Changing patterns of family life have been suggested to be contributing to the rising prevalence of childhood obesity. Objectives: Our primary objective was to examine the relationship between maternal and partner employment and overweight in children aged 3 years. Our secondary objective was to investigate factors related to early childhood overweight only among mothers in employment. Design: Cohort study. Su...

Maternal employment and early childhood overweight: findings from the UK Millennium Cohort Study

OpenAIRE

Hawkins, S. S.; Cole, T. J.; Law, C.; Millennium Cohort Study Child Hlth

2008-01-01

Background: In most developed countries, maternal employment has increased rapidly. Changing patterns of family life have been suggested to be contributing to the rising prevalence of childhood obesity.Objectives: Our primary objective was to examine the relationship between maternal and partner employment and overweight in children aged 3 years. Our secondary objective was to investigate factors related to early childhood overweight only among mothers in employment.Design: Cohort study.Subje...

Stratification for smoking in case-cohort studies of genetic polymorphisms and lung cancer

DEFF Research Database (Denmark)

Sørensen, Mette; López, Ana García; Andersen, Per Kragh

2009-01-01

and adjustment for smoking on the estimated effect of polymorphisms on lung cancer risk was explored in the case-cohort design. We used an empirical and a statistical simulation approach. The stratification strategies were: no smoking stratification, stratification for smoking status and stratification......The risk estimates obtained in studies of genetic polymorphisms and lung cancer differ markedly between studies, which might be due to chance or differences in study design, in particular the stratification/match of comparison group. The effect of different strategies for stratification...... for smoking duration. The study base was a prospective follow-up study with 57,053 participants. In the simulation approach the glutathione S-transferase T1 null polymorphism, as a model of any polymorphism, was added to simulated data in two different ways, assuming either absence or presence of association...

Leisure time physical activity and subsequent physical and mental health functioning among midlife Finnish, British and Japanese employees: a follow-up study in three occupational cohorts

OpenAIRE

Lahti, Jouni; Sabia, S?verine; Singh-Manoux, Archana; Kivim?ki, Mika; Tatsuse, Takashi; Yamada, Masaaki; Sekine, Michikazu; Lallukka, Tea

2016-01-01

OBJECTIVES: The aim of this study was to examine whether leisure time physical activity contributes to subsequent physical and mental health functioning among midlife employees. The associations were tested in three occupational cohorts from Finland, Britain and Japan. DESIGN: Cohort study. SETTING: Finland, Britain and Japan. PARTICIPANTS: Prospective employee cohorts from the Finnish Helsinki Health Study (2000-2002 and 2007, n=5958), British Whitehall II study (1997-1999 and 2003-2004, n=4...

Weight at birth and subsequent fecundability: a prospective cohort study

DEFF Research Database (Denmark)

Nielsen, Cathrine Wildenschild; Hammerich Riis, Anders; Ehrenstein, Vera

2014-01-01

OBJECTIVE: To examine the association between a woman's birth weight and her subsequent fecundability. METHOD: In this prospective cohort study, we included 2,773 Danish pregnancy planners enrolled in the internet-based cohort study "Snart-Gravid", conducted during 2007-2012. Participants were 18...

Apparent and internal validity of a Monte Carlo-Markov model for cardiovascular disease in a cohort follow-up study.

Science.gov (United States)

Nijhuis, Rogier L; Stijnen, Theo; Peeters, Anna; Witteman, Jacqueline C M; Hofman, Albert; Hunink, M G Myriam

2006-01-01

To determine the apparent and internal validity of the Rotterdam Ischemic heart disease & Stroke Computer (RISC) model, a Monte Carlo-Markov model, designed to evaluate the impact of cardiovascular disease (CVD) risk factors and their modification on life expectancy (LE) and cardiovascular disease-free LE (DFLE) in a general population (hereinafter, these will be referred to together as (DF)LE). The model is based on data from the Rotterdam Study, a cohort follow-up study of 6871 subjects aged 55 years and older who visited the research center for risk factor assessment at baseline (1990-1993) and completed a follow-up visit 7 years later (original cohort). The transition probabilities and risk factor trends used in the RISC model were based on data from 3501 subjects (the study cohort). To validate the RISC model, the number of simulated CVD events during 7 years' follow-up were compared with the observed number of events in the study cohort and the original cohort, respectively, and simulated (DF)LEs were compared with the (DF)LEs calculated from multistate life tables. Both in the study cohort and in the original cohort, the simulated distribution of CVD events was consistent with the observed number of events (CVD deaths: 7.1% v. 6.6% and 7.4% v. 7.6%, respectively; non-CVD deaths: 11.2% v. 11.5% and 12.9% v. 13.0%, respectively). The distribution of (DF)LEs estimated with the RISC model consistently encompassed the (DF)LEs calculated with multistate life tables. The simulated events and (DF)LE estimates from the RISC model are consistent with observed data from a cohort follow-up study.

Predictive value of pregnancy history in subfertile couples: results from a nationwide cohort study in the Netherlands

NARCIS (Netherlands)

van der Steeg, Jan W.; Steures, Pieternel; Eijkemans, Marinus J. C.; Habbema, J. Dik F.; Hompes, Peter G. A.; Michgelsen, Henri W. B.; van der Heijden, Pieter F. M.; Bossuyt, Patrick M. M.; van der Veen, Fulco; Mol, Ben W. J.

2008-01-01

OBJECTIVE: To assess whether pregnancy history can predict the occurrence of a spontaneous ongoing pregnancy in subfertile couples. DESIGN: Prospective cohort study. SETTING: Thirty fertility centers in the Netherlands. PATIENT(S): Subfertile, ovulatory women with at least one patent tube and male

Predictive value of pregnancy history in subfertile couples: results from a nationwide cohort study in the Netherlands

NARCIS (Netherlands)

van der Steeg, J.W.; Steures, P.; Eijkemans, M.J.C.; Habbema, J.D.F.; Hompes, P.G.A.; Michgelsen, H.W.B.; van der Heijden, P.F.M.; Bossuyt, P.M.M.; van der Veen, F.; Mol, B.W.J.

2008-01-01

Objective: To assess whether pregnancy history can predict the occurrence of a spontaneous ongoing pregnancy in subfertile couples. Design: Prospective cohort study. Setting: Thirty fertility centers in the Netherlands. Patient(s): Subfertile, ovulatory women with at least one patent tube and male

77 FR 40059 - Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2012-07-06

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health (NIOSH), Centers for... days aggregating at least 250 work days, occurring either solely under this employment or in...

Self reported stress and risk of breast cancer: prospective cohort study

DEFF Research Database (Denmark)

Nielsen, Naja Rod; Zhang, Zuo-Feng; Kristensen, Tage S

2005-01-01

cancer, and impairment of oestrogen synthesis induced by chronic stress may explain a lower incidence of breast cancer in women with high stress. Impairment of normal body function should not, however, be considered a healthy response, and the cumulative health consequences of stress may......OBJECTIVE: To assess the relation between self reported intensity and frequency of stress and first time incidence of primary breast cancer. DESIGN: Prospective cohort study with 18 years of follow-up. SETTING: Copenhagen City heart study, Denmark. PARTICIPANTS: The 6689 women participating...... in the Copenhagen City heart study were asked about their perceived level of stress at baseline in 1981-3. These women were followed until 1999 in the Danish nationwide cancer registry, with

Statins and Hip Fracture Prevention – A Population Based Cohort Study in Women

Science.gov (United States)

Helin-Salmivaara, Arja; Korhonen, Maarit J.; Lehenkari, Petri; Junnila, Seppo Y. T.; Neuvonen, Pertti J.; Ruokoniemi, Päivi; Huupponen, Risto

2012-01-01

Objective To study the association of long-term statin use and the risk of low-energy hip fractures in middle-aged and elderly women. Design A register-based cohort study. Setting Finland. Participants Women aged 45–75 years initiating statin therapy between 1996 and 2001 with adherence to statins ≥80% during the subsequent five years (n = 40 254), a respective cohort initiating hypertension drugs (n = 41 610), and women randomly selected from the population (n = 62 585). Main Outcome Measures Incidence rate of and hazard ratio (HR) for low-energy hip fracture during the follow-up extending up to 7 years after the 5-year exposure period. Results Altogether 199 low-energy hip fractures occurred during the 135 330 person-years (py) of follow-up in the statin cohort, giving an incidence rate of 1.5 hip fractures per 1000 py. In the hypertension and the population cohorts, the rates were 2.0 per 1000 py (312 fractures per 157 090 py) and 1.0 per 1000 py (212 fractures per 216 329 py), respectively. Adjusting for a propensity score and individual variables strongly predicting the outcome, good adherence to statins for five years was associated with a 29% decreased risk (HR 0.71; 95% CI 0.58–0.86) of a low-energy hip fracture in comparison with adherent use of hypertension drugs. The association was of the same magnitude when comparing the statin users with the population cohort, the HR being 0.69 (0.55–0.87). When women with poor (statins were compared to those with good adherence to hypertension drugs (≥80%) or to the population cohort, the protective effect associated with statin use attenuated with the decreasing level of adherence. Conclusions 5-year exposure to statins is associated with a reduced risk of low-energy hip fracture in women aged 50–80 years without prior hospitalizations for fractures. PMID:23144731

Blood pressure and 10-year mortality risk in the Milan Geriatrics 75+ Cohort Study

DEFF Research Database (Denmark)

Ogliari, Giulia; Westendorp, Rudi G J; Muller, Majon

2015-01-01

BACKGROUND: optimal blood pressure targets in older adults are controversial. OBJECTIVE: to investigate whether the relation of blood pressure with mortality in older adults varies by age, functional and cognitive status. DESIGN: longitudinal geriatric outpatient cohort. SETTING: Milan Geriatrics...... 75+ Cohort Study. SUBJECTS: one thousand five hundred and eighty-seven outpatients aged 75 years and over. METHODS: the relations of systolic (SBP) and diastolic blood pressure (DBP) with mortality risk were analysed using Cox proportional hazards models. Blood pressure, Mini-Mental State Examination......: the correlations of SBP and DBP with mortality were U-shaped. Higher SBP is related to lower mortality in subjects with impaired ADL and MMSE. ADL and MMSE may identify older subjects who benefit from higher blood pressure....

MR imaging of the brain in large cohort studies: feasibility report of the population- and patient-based BiDirect study

International Nuclear Information System (INIS)

Teuber, Anja; Berger, Klaus; Wersching, Heike; Sundermann, Benedikt; Kugel, Harald; Schwindt, Wolfram; Heindel, Walter; Minnerup, Jens; Dannlowski, Udo

2017-01-01

To describe the implementation and protocol of cerebral magnetic resonance imaging (MRI) in the longitudinal BiDirect study and to report rates of study participation as well as management of incidental findings. Data came from the BiDirect study that investigates the relationship between depression and arteriosclerosis and comprises 2258 participants in three cohorts: 999 patients with depression, 347 patients with manifest cardiovascular disease (CVD) and 912 population-based controls. The study program includes MRI of the brain. Reasons for non-participation were systematically collected. Incidental findings were categorized and disclosed according to clinical relevance. At baseline 2176 participants were offered MRI, of whom 1453 (67 %) completed it. Reasons for non-participation differed according to cohort, age and gender with controls showing the highest participation rate of 79 %. Patient cohorts had higher refusal rates and CVD patients a high prevalence of contraindications. In the first follow-up examination 69 % of participating subjects completed MRI. Incidental findings were disclosed to 246 participants (17 %). The majority of incidental findings were extensive white matter hyperintensities requiring further diagnostic work-up. Knowledge about subjects and sensible definition of incidental findings are crucial for large-scale imaging projects. Our data offer practical and concrete information for the design of future studies. (orig.)

MR imaging of the brain in large cohort studies: feasibility report of the population- and patient-based BiDirect study

Energy Technology Data Exchange (ETDEWEB)

Teuber, Anja; Berger, Klaus; Wersching, Heike [University of Muenster, Institute of Epidemiology and Social Medicine, Muenster (Germany); Sundermann, Benedikt; Kugel, Harald; Schwindt, Wolfram; Heindel, Walter [University Hospital Muenster, Department of Clinical Radiology, Muenster (Germany); Minnerup, Jens [University Hospital Muenster, Department of Neurology, Muenster (Germany); Dannlowski, Udo [University of Muenster, Department of Psychiatry, Muenster (Germany); University of Marburg, Department of Psychiatry, Marburg (Germany)

2017-01-15

To describe the implementation and protocol of cerebral magnetic resonance imaging (MRI) in the longitudinal BiDirect study and to report rates of study participation as well as management of incidental findings. Data came from the BiDirect study that investigates the relationship between depression and arteriosclerosis and comprises 2258 participants in three cohorts: 999 patients with depression, 347 patients with manifest cardiovascular disease (CVD) and 912 population-based controls. The study program includes MRI of the brain. Reasons for non-participation were systematically collected. Incidental findings were categorized and disclosed according to clinical relevance. At baseline 2176 participants were offered MRI, of whom 1453 (67 %) completed it. Reasons for non-participation differed according to cohort, age and gender with controls showing the highest participation rate of 79 %. Patient cohorts had higher refusal rates and CVD patients a high prevalence of contraindications. In the first follow-up examination 69 % of participating subjects completed MRI. Incidental findings were disclosed to 246 participants (17 %). The majority of incidental findings were extensive white matter hyperintensities requiring further diagnostic work-up. Knowledge about subjects and sensible definition of incidental findings are crucial for large-scale imaging projects. Our data offer practical and concrete information for the design of future studies. (orig.)

The Netherlands Cohort Study – Meat Investigation Cohort; a population-based cohort over-represented with vegetarians, pescetarians and low meat consumers

Science.gov (United States)

2013-01-01

Background Vegetarian diets have been associated with lower risk of chronic disease, but little is known about the health effects of low meat diets and the reliability of self-reported vegetarian status. We aimed to establish an analytical cohort over-represented with vegetarians, pescetarians and 1 day/week meat consumers, and to describe their lifestyle and dietary characteristics. In addition, we were able to compare self-reported vegetarians with vegetarians whose status has been confirmed by their response on the extensive food frequency questionnaire (FFQ). Study methods Embedded within the Netherlands Cohort Study (n = 120,852; including 1150 self-reported vegetarians), the NLCS-Meat Investigation Cohort (NLCS-MIC) was defined by combining all FFQ-confirmed-vegetarians (n = 702), pescetarians (n = 394), and 1 day/week meat consumers (n = 1,396) from the total cohort with a random sample of 2–5 days/week- and 6–7 days/week meat consumers (n = 2,965 and 5,648, respectively). Results Vegetarians, pescetarians, and 1 day/week meat consumers had more favorable dietary intakes (e.g. higher fiber/vegetables) and lifestyle characteristics (e.g. lower smoking rates) compared to regular meat consumers in both sexes. Vegetarians adhered to their diet longer than pescetarians and 1 day/week meat consumers. 75% of vegetarians with a prevalent cancer at baseline had changed to this diet after diagnosis. 50% of self-reported vegetarians reported meat or fish consumption on the FFQ. Although the misclassification that occurred in terms of diet and lifestyle when merely relying on self-reporting was relatively small, the impact on associations with disease risk remains to be studied. Conclusion We established an analytical cohort over-represented with persons at the lower end of the meat consumption spectrum which should facilitate prospective studies of major cancers and causes of death using ≥20.3 years of follow-up. PMID:24289207

Cohort Profile: The JS High School study (JSHS): a cohort study of Korean adolescents.

Science.gov (United States)

Choi, Dong Phil; Lee, Joo Young; Kim, Hyeon Chang

2017-04-01

Major aetiologies of atherosclerotic cardiovascular diseases begin in childhood and atherosclerotic vascular abnormalities can be observed among children and adolescents. Adolescent cohort studies have important advantages because they can observe earlier changes in vascular structure and function. The purpose of the JS High School study (JSHS) is to identify biomarkers predicting or indicating early structural and functional vascular change in adolescents. The JSHS is a prospective cohort study of a Korean adolescent population. The target population of the JSHS was first-graders (aged 14 to17 years) at a high school of South Korea. Enrolment and baseline examinations were conducted in years 2007, 2010, 2011 and 2012. Among the total eligible population of 1115 students, 1071 (96.1%) participated in the study and completed all baseline examinations. Informed consent forms were obtained from each participant and his/her parent or guardian. Baseline examinations include: questionnaires on demographics, health behaviours, medical history, and depression symptoms; fasting blood analysis; anthropometric measurement; body impedance analysis; blood pressure measurement; radial artery tonometry; bone densitometry; pulmonary function tests; and carotid ultrasonography. Participants enrolled from 2007 through 2012 were re-examined after 30 months of follow-up, and those who enrolled in 2012 were re-examined after 24 months of follow-up. The corresponding author may be contacted for potential collaboration and data access. © The Author 2015; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

77 FR 9251 - Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2012-02-16

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health (NIOSH), Centers for..., for a number of work days aggregating at least 250 work days, occurring either solely under this...

The Fender Stratocaster Electric Guitar: A Case Study for both Nontransferable and Transferable Skills Learning in a Generalist Electronic Engineering Cohort

Science.gov (United States)

Joyce, M. J.

2010-01-01

A case-study approach to teaching electronics system design that has been used since 2004 to demonstrate the importance of both nontransferable and transferable design issues to first-year undergraduate students is described. The student cohort of relevance to this work represents a diverse group comprising both students studying for a four-year…

77 FR 15759 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2012-03-16

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a...

78 FR 21955 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2013-04-12

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a...

78 FR 70949 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2013-11-27

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a...

77 FR 60438 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2012-10-03

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a...

75 FR 27784 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2010-05-18

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... concerning the final effect of the decision to designate a class of employees from Lawrence Livermore...

75 FR 37812 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2010-06-30

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... and Human Services (HHS) gives notice concerning the final effect of the HHS decision to designate a...

77 FR 60437 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2012-10-03

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a...

77 FR 69845 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2012-11-21

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a...

78 FR 21954 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2013-04-12

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health...). ACTION: Notice. SUMMARY: HHS gives notice concerning the final effect of the HHS decision to designate a...

Cohort Differences in Cognitive Aging in the Longitudinal Aging Study Amsterdam.

Science.gov (United States)

Brailean, Anamaria; Huisman, Martijn; Prince, Martin; Prina, A Matthew; Deeg, Dorly J H; Comijs, Hannie

2016-09-30

This study aims to examine cohort differences in cognitive performance and rates of change in episodic memory, processing speed, inductive reasoning, and general cognitive performance and to investigate whether these cohort effects may be accounted for by education attainment. The first cohort (N = 705) was born between 1920 and 1930, whereas the second cohort (N = 646) was born between 1931 and 1941. Both birth cohorts were aged 65 to 75 years at baseline and were followed up 3 and 6 years later. Data were analyzed using linear mixed models. The later born cohort had better general cognitive performance, inductive reasoning, and processing speed at baseline, but cohort differences in inductive reasoning and general cognitive performance disappeared after adjusting for education. The later born cohort showed steeper decline in processing speed. Memory decline was steeper in the earlier born cohort but only from Time 1 to Time 3 when the same memory test was administered. Education did not account for cohort differences in cognitive decline. The later born cohort showed better initial performance in certain cognitive abilities, but no better preservation of cognitive abilities overtime compared with the earlier born cohort. These findings carry implications for healthy cognitive aging. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America.

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.

The radiologic technologists' health study in South Korea: study design and baseline results.

Science.gov (United States)

Lee, Won Jin; Ha, Mina; Hwang, Seung-sik; Lee, Kyoung-Mu; Jin, Young-Woo; Jeong, Meeseon; Jun, Jae Kwan; Cha, Eun Shil; Ko, Yousun; Choi, Kyung-Hwa; Lee, Jung-Eun

2015-08-01

To describe the study design, methods, and baseline results of a prospective cohort of radiologic technologists which we have initiated in South Korea. The cohort participants were enrolled through a self-administered questionnaire survey administered from April 2012 to May 2013. Survey data were linked with radiation dosimetry, a cancer registry, and health insurance data by personal identification numbers. A nationwide representative survey was also conducted using a stratified random sampling design with face-to-face interviews. A total of 12,387 radiologic technologists were enrolled, which accounted for approximately 63% of all diagnostic radiologic technologists working in South Korea. For nationwide survey, 585 workers were interviewed using the detailed questionnaire, and buccal cells were also collected by scraping the inside of the cheek. The majority of study subjects were under 50-year-old and male workers. The average annual effective dose of radiation declined both men (from 2.75 to 1.43 mSv) and women (from 1.34 to 0.95 mSv) over the period of 1996-2011. A total of 99 cancers (66 cancers in men and 33 in women) were reported from 1992 to 2010. The standardized incidence ratio of all cancer combined was significantly lower in men (SIR = 0.75, 95% CI 0.58-0.96) than general population, but the ratios for thyroid cancer were significantly higher than expected among both men and women. This cohort provides comprehensive information on work activities and health status of diagnostic radiologic technologists. In addition, the nationwide representative sample provides unique opportunities compared with previous radiologic technologist studies.

The radiologic technologists' health study in South Korea. Study design and baseline results

International Nuclear Information System (INIS)

Lee, Won Jin; Ha, Mina; Hwang, Seung-sik

2015-01-01

To describe the study design, methods, and baseline results of a prospective cohort of radiologic technologists which we have initiated in South Korea. The cohort participants were enrolled through a self-administered questionnaire survey administered from April 2012 to May 2013. Survey data were linked with radiation dosimetry, a cancer registry, and health insurance data by personal identification numbers. A nationwide representative survey was also conducted using a stratified random sampling design with face-to-face interviews. A total of 12,387 radiologic technologists were enrolled, which accounted for approximately 63 % of all diagnostic radiologic technologists working in South Korea. For nationwide survey, 585 workers were interviewed using the detailed questionnaire, and buccal cells were also collected by scraping the inside of the cheek. The majority of study subjects were under 50-year-old and male workers. The average annual effective dose of radiation declined both men (from 2.75 to 1.43 mSv) and women (from 1.34 to 0.95 mSv) over the period of 1996-2011. A total of 99 cancers (66 cancers in men and 33 in women) were reported from 1992 to 2010. The standardized incidence ratio of all cancer combined was significantly lower in men (SIR = 0.75, 95 % CI 0.58-0.96) than general population, but the ratios for thyroid cancer were significantly higher than expected among both men and women. This cohort provides comprehensive information on work activities and health status of diagnostic radiologic technologists. In addition, the nationwide representative sample provides unique opportunities compared with previous radiologic technologist studies.

76 FR 72928 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2011-11-28

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... concerning the final effect of the HHS decision to designate a class of employees from Vitro Manufacturing in...

76 FR 7852 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

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2011-02-11

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... concerning the final effect of the HHS decision to designate a class of employees from Texas City Chemicals...

76 FR 59701 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

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2011-09-27

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... concerning the final effect of the HHS decision to designate a class of employees from the Sandia National...

75 FR 67364 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

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2010-11-02

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... concerning the final effect of the HHS decision to designate a class of employees from the Blockson Chemical...

75 FR 27785 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2010-05-18

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... concerning the final effect of the decision to designate a class of employees from Area IV of the Santa...

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study

OpenAIRE

López Gómez, María Andreé, 1985-; Duran Jordà, Xavier, 1974-; Zaballa, Elena; Sánchez Niubò, Albert; Delclòs i Clanchet, Jordi, 1956-; Benavides, Fernando G. (Fernando García)

2016-01-01

PURPOSE: The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and deat...

Maternal antecedents of adiposity and studying the transgenerational role of hyperglycemia and insulin (MAASTHI): a prospective cohort study : Protocol of birth cohort at Bangalore, India.

Science.gov (United States)

Babu, Giridhara R; Murthy, Gvs; Deepa, R; Yamuna; Prafulla; Kumar, H Kiran; Karthik, Maithili; Deshpande, Keerti; Benjamin Neelon, Sara E; Prabhakaran, D; Kurpad, Anura; Kinra, Sanjay

2016-10-14

India is experiencing an epidemic of obesity-hyperglycaemia, which coincides with child bearing age for women. The epidemic can be sustained and augmented through transgenerational transmission of adiposity and glucose intolerance in women. This presents an opportunity for exploring a clear strategy for the control of this epidemic in India. We conducted a study between November 2013 and May 2015 to inform the design of a large pregnancy cohort study. Based on the findings of this pilot, we developed the protocol for the proposed birth cohort of 5000 women, the recruitment for which will start in April 2016. The protocol of the study documents the processes which aim at advancing the available knowledge, linking several steps in the evolution of obesity led hyperglycemia. Maternal Antecedents of Adiposity and Studying the Transgenerational role of Hyperglycemia and Insulin (MAASTHI) is a cohort study in the public health facilities in Bangalore, India. The objective of MAASTHI is to prospectively assess the effects of glucose levels in pregnancy on the risk of adverse infant outcomes, especially in predicting the possible risk markers of later chronic diseases. The primary objective of the proposed study is to investigate the effect of glucose levels in pregnancy on skinfold thickness (adiposity) in infancy as a marker of future obesity and diabetes in offspring. The secondary objective is to assess the association between psychosocial environment of mothers and adverse neonatal outcomes including adiposity. The study aims to recruit 5000 pregnant women and follow them and their offspring for a period of 4 years. The institutional review board at The Indian Institute of Public Health (IIPH)-H, Bangalore, Public Health Foundation of India has approved the protocol. All participants are required to provide written informed consent. The findings from this study may help to address important questions on screening and management of high blood sugar in pregnancy. It

The difference in blood pressure readings between arms and survival: primary care cohort study

OpenAIRE

Clark, Christopher E; Taylor, Rod S; Shore, Angela C; Campbell, John L

2012-01-01

Objective To determine whether a difference in systolic blood pressure readings between arms can predict a reduced event free survival after 10 years. Design Cohort study. Setting Rural general practice in Devon, United Kingdom. Participants 230 people receiving treatment for hypertension in primary care. Intervention Bilateral blood pressure measurements recorded at three successive surgery attendances. Main outcome measures Cardiovascular events and deaths from all causes during a median fo...

Quality of life before and after TVT, a prospective multicentre cohort study, results from the Netherlands TVT database

NARCIS (Netherlands)

Koops, SES; Bisseling, TM; Heintz, APM; Vervest, HAM

Objective To asses the long term outcome of tension-free vaginal tape procedure in women with isolated stress urinary incontinence (SUI). Design Prospective cohort study. Setting Twenty-eight teaching hospitals and 13 local hospitals, with 54 gynaecologists and urologists performing the surgery.

International retrospective cohort study of neural tube defects in relation to folic acid recommendations : are the recommendations working?

NARCIS (Netherlands)

Botto, LD; Lisi, A; Robert-Gnansia, E; Erickson, JD; Vollset, SE; Mastroiacovo, P; Botting, B; Cocchi, G; de Vigan, C; de Walle, H; Feijoo, M; Irgens, LM; McDonnell, B; Merlob, P; Ritvanen, A; Scarano, G; Siffel, C; Metneki, J; Stoll, C; Smithells, R; Goujard, J

2005-01-01

Objective To evaluate the effectiveness of policies and recommendations on folic acid aimed at reducing the occurrence of neural tube defects. Design Retrospective cohort study of births monitored by birth defect registries. Setting 13 birth defects registries monitoring rates of neural tube defects

High quantitative job demands and low coworker support as risk factors for neck pain: Results of a prospective cohort study

NARCIS (Netherlands)

Ariëns, G.A.M.; Bongers, P.M.; Hoogendoorn, W.E.; Houtman, I.L.D.; Wal, G. van der; Mechelen, W. van

2001-01-01

Study Design. A 3-year prospective cohort study among 1334 workers was conducted. Objective. To determine whether the work-related psychosocial factors of quantitative job demands, conflicting job demands, skill discretion, decision authority, supervisor support, coworker support, and job security

Alcohol and ovarian cancer risk: Results from the Netherlands Cohort Study

NARCIS (Netherlands)

Schouten, L.J.; Zeegers, M.P.A.; Goldbohm, R.A.; Brandt, P.A. van den

2004-01-01

Objective: To study alcohol consumption in relation to ovarian cancer risk in a prospective cohort study. Methods: The Netherlands Cohort Study on diet and cancer was initiated in 1986. A self-administered questionnaire on dietary habits and other risk factors for cancer was completed by 62,573

Prospective validation of a prognostic model for respiratory syncytial virus bronchiolitis in late preterm infants: a multicenter birth cohort study

NARCIS (Netherlands)

Blanken, M.O.; Koffijberg, H.; Nibbelke, E.E.; Rovers, M.M.; Bont, L.; Liem, K.D.; et al.,

2013-01-01

OBJECTIVES: This study aimed to update and validate a prediction rule for respiratory syncytial virus (RSV) hospitalization in preterm infants 33-35 weeks gestational age (WGA). STUDY DESIGN: The RISK study consisted of 2 multicenter prospective birth cohorts in 41 hospitals. Risk factors were

Pregnancy periodontitis and low birth weight: A cohort study in rural Belgaum, India

Directory of Open Access Journals (Sweden)

Murthy S

2012-01-01

Full Text Available Background: Low birth weight can cause devastating long term medical and economical impacts to the family as whole and much interest prevails in preventing LBW by controlling its potential risk factors. Pregnancy periodontitis, being reported as one of such risk factors, is amenable to prevention, control and cure. Confirmative evidence can bring drastic improvements in birth weight and also health of the mother. This cohort study was an attempt to find if such a relation exists since limited conclusive evidence is available. Objectives: To determine the relation between pregnancy periodontitis and low birth weight of newborn in primigravida women in rural Belgaum. To assess the oral health status of the same primigravida women in rural Belgaum. Materials & Methods:Study Design & Period: A cohort study for 18 months Study location: 3 rural field areas of JNMC (Handiganur, Kinaye and Vantamuri in Belgaum. Study Population: Primigravida women in the 3 villages in their first trimester in January/February 2011 during enrolment and expected to deliver in August/September 2011. Sample Size: 240 (120 in each cohort. Data Collection: After ethical review, a pilot study was conducted on 10% of study population in each village to essentially pre-test the interview schedule. Then screening visit to enrol women based on eligibility criteria was done. Subsequent screening periodontal examination was done by CPI to allocate the women into study (pregnant women with periodontitis and control (pregnant women without periodontitis cohort. Oral health status was also recorded using OHI-S and DMFT indices. Follow up visits consisted of trimester-wise visit to check on periodontal status and a post delivery visit to record term of delivery and LBW. Data was entered in Microsoft Excel 2007 and SPSS (β version 20 and analyzed in in proportions, percentages, Odds Ratio, Relative Risk, Chi-Square test and Logistic Regression Analysis.Results: The total incidence of

Pregnancy periodontitis and low birth weight: A cohort study in rural Belgaum, India

Directory of Open Access Journals (Sweden)

Murthy S

2012-07-01

Full Text Available Background: Low birth weight can cause devastating long term medical and economical impacts to the family as whole and much interest prevails in preventing LBW by controlling its potential risk factors. Pregnancy periodontitis, being reported as one of such risk factors, is amenable to prevention, control and cure. Confirmative evidence can bring drastic improvements in birth weight and also health of the mother. This cohort study was an attempt to find if such a relation exists since limited conclusive evidence is available. Objectives: To determine the relation between pregnancy periodontitis and low birth weight of newborn in primigravida women in rural Belgaum. To assess the oral health status of the same primigravida women in rural Belgaum. Materials & Methods: Study Design & Period: A cohort study for 18 months Study location: 3 rural field areas of JNMC (Handiganur, Kinaye and Vantamuri in Belgaum. Study Population: Primigravida women in the 3 villages in their first trimester in January/February 2011 during enrolment and expected to deliver in August/September 2011. Sample Size: 240 (120 in each cohort. Data Collection: After ethical review, a pilot study was conducted on 10% of study population in each village to essentially pre-test the interview schedule. Then screening visit to enrol women based on eligibility criteria was done. Subsequent screening periodontal examination was done by CPI to allocate the women into study (pregnant women with periodontitis and control (pregnant women without periodontitis cohort. Oral health status was also recorded using OHI-S and DMFT indices. Follow up visits consisted of trimester-wise visit to check on periodontal status and a post delivery visit to record term of delivery and LBW. Data was entered in Microsoft Excel 2007 and SPSS (β version 20 and analyzed in in proportions, percentages, Odds Ratio, Relative Risk, Chi-Square test and Logistic Regression Analysis.Results: The total incidence of

Childhood obesity trends from primary care electronic health records in England between 1994 and 2013: population-based cohort study

NARCIS (Netherlands)

Jaarsveld, C.H.M. van; Gulliford, M.C.

2015-01-01

OBJECTIVE: This study aimed to use primary care electronic health records to evaluate the prevalence of overweight and obesity in 2-15-year-old children in England and compare trends over the last two decades. DESIGN: Cohort study of primary care electronic health records. SETTING: 375 general

Classification of patients with sepsis according to blood genomic endotype: a prospective cohort study.

Science.gov (United States)

Scicluna, Brendon P; van Vught, Lonneke A; Zwinderman, Aeilko H; Wiewel, Maryse A; Davenport, Emma E; Burnham, Katie L; Nürnberg, Peter; Schultz, Marcus J; Horn, Janneke; Cremer, Olaf L; Bonten, Marc J; Hinds, Charles J; Wong, Hector R; Knight, Julian C; van der Poll, Tom

2017-10-01

Host responses during sepsis are highly heterogeneous, which hampers the identification of patients at high risk of mortality and their selection for targeted therapies. In this study, we aimed to identify biologically relevant molecular endotypes in patients with sepsis. This was a prospective observational cohort study that included consecutive patients admitted for sepsis to two intensive care units (ICUs) in the Netherlands between Jan 1, 2011, and July 20, 2012 (discovery and first validation cohorts) and patients admitted with sepsis due to community-acquired pneumonia to 29 ICUs in the UK (second validation cohort). We generated genome-wide blood gene expression profiles from admission samples and analysed them by unsupervised consensus clustering and machine learning. The primary objective of this study was to establish endotypes for patients with sepsis, and assess the association of these endotypes with clinical traits and survival outcomes. We also established candidate biomarkers for the endotypes to allow identification of patient endotypes in clinical practice. The discovery cohort had 306 patients, the first validation cohort had 216, and the second validation cohort had 265 patients. Four molecular endotypes for sepsis, designated Mars1-4, were identified in the discovery cohort, and were associated with 28-day mortality (log-rank p=0·022). In the discovery cohort, the worst outcome was found for patients classified as having a Mars1 endotype, and at 28 days, 35 (39%) of 90 people with a Mars1 endotype had died (hazard ratio [HR] vs all other endotypes 1·86 [95% CI 1·21-2·86]; p=0·0045), compared with 23 (22%) of 105 people with a Mars2 endotype (HR 0·64 [0·40-1·04]; p=0·061), 16 (23%) of 71 people with a Mars3 endotype (HR 0·71 [0·41-1·22]; p=0·19), and 13 (33%) of 40 patients with a Mars4 endotype (HR 1·13 [0·63-2·04]; p=0·69). Analysis of the net reclassification improvement using a combined clinical and endotype model

Outcome after resuscitation beyond 30 minutes in drowned children with cardiac arrest and hypothermia : Dutch nationwide retrospective cohort study

NARCIS (Netherlands)

Kieboom, J. K.; Verkade, H. J.; Burgerhof, J. G.; Bierens, J. J.; van Rheenen, P. F.; Kneyber, M. C.; Albers, M. J.

2015-01-01

OBJECTIVES To evaluate the outcome of drowned children with cardiac arrest and hypothermia, and to determine distinct criteria for termination of cardiopulmonary resuscitation in drowned children with hypothermia and absence of spontaneous circulation. DESIGN Nationwide retrospective cohort study.

Palliative sedation in Dutch general practice from 2005 to 2011: a dynamic cohort study of trends and reasons.

NARCIS (Netherlands)

Donker, G.A.; Slotman, F.G.; Spreeuwenberg, P.; Francke, A.L.

2013-01-01

Background: Little is known about the quantity and reasons for use of palliative sedation in general practice. Aim: To gain more insight into the trends of and reasons for palliative sedation in Dutch general practice. Design and setting: Dynamic cohort study using registrations and questionnaire

Palliative sedation in Dutch general practice from 2005 to 2011: a dynamic cohort study of trends and reasons

NARCIS (Netherlands)

Donker, G.A.; Slotman, F.G.; Spreeuwenberg, P.; Francke, A.L.

2013-01-01

Background: Little is known about the quantity and reasons for use of palliative sedation in general practice. Aim: To gain more insight into the trends of and reasons for palliative sedation in Dutch general practice. Design and setting: Dynamic cohort study using registrations and questionnaire

Distress among young adult cancer survivors: a cohort study.

Science.gov (United States)

Yanez, Betina; Garcia, Sofia F; Victorson, David; Salsman, John M

2013-09-01

Being diagnosed with cancer as a young adult can lead to significant psychological distress and impaired quality of life. Compared to children and older adults diagnosed with cancer, fewer studies have addressed psychological distress among young adult cancer survivors. This study sought to identify the prevalence of, and factors associated with, distress among young adult cancer survivors (ages 18-39). Young adult cancer survivors (N = 335, mean age = 31.8, women = 68.4%) were recruited from an online research panel and stratified by cohort (time postactive treatment: 0-12, 13-24, and 25-60 months). Participants completed measures assessing demographic and clinical characteristics, global impact of cancer, cancer-related education and work interruption, and cancer-specific distress using the impact of event scale (IES). The mean score on the IES (M = 31.0, range = 0-75) was above the cut point of 20, suggesting clinically elevated distress. Analysis of covariance revealed significant main effects for cohort, global impact and cancer-related education/work interruption, and an interaction between cohort and cancer-related education/work interruption on distress. Although there was no significant effect of education/work interruption on distress for those in the 0-12 month cohort (p = .88), survivors in the 13-24 and 25-60 month cohorts reporting education/work interruption were significantly more distressed than those not reporting education/work interruption in the respective cohorts (p cancer survivors face unique challenges. These data underscore the importance of attending to cancer-related distress beyond the completion of treatment and may help inform targeted interventions to prevent or reduce significant distress and related sequelae in this population.

Frailty and type of death among older adults in China: prospective cohort study

OpenAIRE

Dupre, Matthew E; Gu, Danan; Warner, David F; Yi, Zeng

2009-01-01

Objective To examine the association between frailty and type of death among the world?s largest oldest-old population in China. Design Prospective cohort study. Setting 2002 and 2005 waves of the Chinese longitudinal healthy longevity survey carried out in 22 provinces throughout China. Participants 13?717 older adults (aged ?65). Main outcome measures Type of death, categorised as being bedridden for fewer than 30 days with or without suffering and being bedridden for 30 or more days with o...

Short-Term Absenteeism and Health Care Utilization Due to Lower Extremity Injuries Among Novice Runners : A Prospective Cohort Study

NARCIS (Netherlands)

Smits, Dirk-Wouter; Huisstede, Bionka; Verhagen, Evert; van der Worp, Henk; Kluitenberg, Bas; van Middelkoop, Marienke; Hartgens, Fred; Backx, Frank

2016-01-01

Objective: To describe absenteeism and health care utilization (HCU) within 6 weeks after occurrence of running-related injuries (RRIs) among novice runners and to explore differences relating to injury and personal characteristics. Design: Prospective cohort study. Setting: Primary care.

Quantifying the benefits of achieving or maintaining long-term low risk profile for cardiovascular disease : The doetinchem cohort study

NARCIS (Netherlands)

Hulsegge, Gerben; Smit, Henriëtte A.; Van Der Schouw, Yvonne T.; Daviglus, Martha L.; Verschuren, W. M Monique

2015-01-01

Background: Studies investigating the relation between risk profiles and cardiovascular disease have measured risk at baseline only. We investigated maintenance and changes of risk profiles over time and their potential impact on incident cardiovascular disease. Design: Population-based cohort

Quantifying the benefits of achieving or maintaining long-term low risk profile for cardiovascular disease: The Doetinchem Cohort Study

NARCIS (Netherlands)

Hulsegge, G.; Smit, H.A.; van der Schouw, Y.T.; Daviglus, M.L.; Verschuren, W.M.

2015-01-01

Background: Studies investigating the relation between risk profiles and cardiovascular disease have measured risk at baseline only. We investigated maintenance and changes of risk profiles over time and their potential impact on incident cardiovascular disease. Design: Population-based cohort

STATUS REPORT, BEGIN TO DEVELOP COMPLETE OPERATIONS MANUALS FOR THE COHORT: PREPARE TO IMPLEMENT A COHORT STUDY OF CHILDREN'S ENVIRONMENTAL HEALTH

Science.gov (United States)

As a precursor to the National Children's Study (NCS), the North Carolina Cohort Study (NC Cohort Study) will provide the opportunity to field test procedures to better inform the implementation of the NCS. In order to test some of the study hypotheses, it will be important to ob...

Natural history and surgical treatment of chordoma: a retrospective cohort study

Directory of Open Access Journals (Sweden)

Samuel Aguiar Júnior

Full Text Available CONTEXT AND OBJECTIVE: Chordoma is a rare tumor with a high risk of locoregional recurrences. The aim of this study was analyze the long-term results from treating this pathological condition.DESIGN AND SETTING: Cohort study in a single hospital in São Paulo, Brazil.METHODS: This was a retrospective cohort study on 42 patients with chordoma who were treated at Hospital A. C. Camargo between 1980 and 2006. The hospital records were reviewed and a descriptive analysis was performed on the clinical-pathological variables. Survival curves were estimated using the Kaplan-Meier method and these were compared using the log-rank test.RESULTS: Nineteen patients were men and 23 were women. Twenty-five tumors (59.5% were located in the sacrum, eleven (26.2% in the skull base and six (14.3% in the mobile spine. Surgery was performed on 28 patients (66.7%. The resection was considered to have negative margins in 14 cases and positive margins in 14 cases. The five-year overall survival (OS was 45.4%. For surgical patients, the five-year OS was 64.3% (82.2% for negative margins and 51.9% for positive margins. In the inoperable group, OS was 37.7% at 24 months and 0% at five years.CONCLUSION: Complete resection is related to local control and definitively has a positive impact on long-term survival.

The radiologic technologists' health study in South Korea. Study design and baseline results

Energy Technology Data Exchange (ETDEWEB)

Lee, Won Jin [Korea Univ. College of Medicine, Seoul (Korea, Republic of). Dept. of Preventive Medicine; Ha, Mina [Dankook Univ. College of Medicine, Cheonan (Korea, Republic of). Dept. of Preventive Medicine; Hwang, Seung-sik [Inha Univ. School of Medicine, Incheon (Korea, Republic of). Dept. of Social and Preventive Medicine; and others

2015-08-15

To describe the study design, methods, and baseline results of a prospective cohort of radiologic technologists which we have initiated in South Korea. The cohort participants were enrolled through a self-administered questionnaire survey administered from April 2012 to May 2013. Survey data were linked with radiation dosimetry, a cancer registry, and health insurance data by personal identification numbers. A nationwide representative survey was also conducted using a stratified random sampling design with face-to-face interviews. A total of 12,387 radiologic technologists were enrolled, which accounted for approximately 63 % of all diagnostic radiologic technologists working in South Korea. For nationwide survey, 585 workers were interviewed using the detailed questionnaire, and buccal cells were also collected by scraping the inside of the cheek. The majority of study subjects were under 50-year-old and male workers. The average annual effective dose of radiation declined both men (from 2.75 to 1.43 mSv) and women (from 1.34 to 0.95 mSv) over the period of 1996-2011. A total of 99 cancers (66 cancers in men and 33 in women) were reported from 1992 to 2010. The standardized incidence ratio of all cancer combined was significantly lower in men (SIR = 0.75, 95 % CI 0.58-0.96) than general population, but the ratios for thyroid cancer were significantly higher than expected among both men and women. This cohort provides comprehensive information on work activities and health status of diagnostic radiologic technologists. In addition, the nationwide representative sample provides unique opportunities compared with previous radiologic technologist studies.

Historic cohort study in Montreal's fur industry.

Science.gov (United States)

Guay, D; Siemiatycki, J

1987-01-01

A historic cohort mortality study was carried out among two groups of male workers in the Montreal fur industry: 263 dressers and dyers and 599 fur garment manufacturers. The first group is exposed to a very wide variety of chemicals used in tanning, cleaning, and dyeing fur, including substances considered to be carcinogenic and/or mutagenic. The second group is exposed to residue from the dressing and dyeing stage and to respirable fur dust. The cohorts consisted of all active members of two unions as of January 1, 1966. The mean age of the workers was 43.2 and the mean number of years since first employment 14.1. The follow-up period was from January 1, 1966, to December 31, 1981; 95% of the workers were successfully traced. Observed deaths were compared with those expected based on mortality rates of the population of metropolitan Montreal. Standardized mortality ratios (SMRs) for the manufacturers were significantly low, probably because of the ethnic composition of the cohort and a healthy worker effect. SMRs for the dressers and dyers were also low, but not as low as for the manufacturers. When attention was restricted to the French Canadians in the cohort, the observed deaths were close to the expected; there was a noteworthy excess of colorectal cancer (four observed, 0.8 expected) for dressers and dyers. Apart from this weak suggestive evidence, the results did not indicate any excess mortality risks in the fur industry. However, because of the relatively small number of expected and observed deaths in the cohort and especially among the heavily exposed dressers and dyers, the confidence intervals around SMR estimates were wide and excess risks cannot be ruled out.

Gulf war illness—better, worse, or just the same? A cohort study

Science.gov (United States)

Hotopf, Matthew; David, Anthony S; Hull, Lisa; Nikalaou, Vasilis; Unwin, Catherine; Wessely, Simon

2003-01-01

Objectives Firstly, to describe changes in the health of Gulf war veterans studied in a previous occupational cohort study and to compare outcome with comparable non-deployed military personnel. Secondly, to determine whether differences in prevalence between Gulf veterans and controls at follow up can be explained by greater persistence or greater incidence of disorders. Design Occupational cohort study in the form of a postal survey. Participants Military personnel who served in the 1991 Persian Gulf war; personnel who served on peacekeeping duties to Bosnia; military personnel who were deployed elsewhere (“Era” controls). All participants had responded to a previous survey. Setting United Kingdom. Main outcome measures Self reported fatigue measured on the Chalder fatigue scale; psychological distress measured on the general health questionnaire, physical functioning and health perception on the SF-36; and a count of physical symptoms. Results Gulf war veterans experienced a modest reduction in prevalence of fatigue (48.8% at stage 1, 43.4% at stage 2) and psychological distress (40.0% stage 1, 37.1% stage 2) but a slight worsening of physical functioning on the SF-36 (90.3 stage 1, 88.7 stage 2). Compared with the other cohorts Gulf veterans continued to experience poorer health on all outcomes, although physical functioning also declined in Bosnia veterans. Era controls showed both lower incidence of fatigue than Gulf veterans, and both comparison groups showed less persistence of fatigue compared with Gulf veterans. Conclusions Gulf war veterans remain a group with many symptoms of ill health. The excess of illness at follow up is explained by both higher incidence and greater persistence of symptoms. PMID:14670878

Changes in Pulmonary Function During the Early Years After Inpatient Rehabilitation in Persons With Spinal Cord Injury : A Prospective Cohort Study

NARCIS (Netherlands)

Haisma, Janneke A.; de Groot, Sonja; Hopman, Maria T.; Bergen, Michael. P.; Stam, Henk J.; Bussmann, Johannes B.; Postma, K.

Objective: To describe changes in pulmonary function (PF) during the 5 years after inpatient rehabilitation in persons with spinal cord injury (SCI) and to study potential determinants of change. Design: Prospective cohort study. Setting: Eight rehabilitation centers with specialized SCI units.

Harmonising measures of knee and hip osteoarthritis in population-based cohort studies

DEFF Research Database (Denmark)

Leyland, K M; Gates, L S; Nevitt, M

2018-01-01

OBJECTIVE: Population-based osteoarthritis (OA) cohorts provide vital data on risk factors and outcomes of OA, however the methods to define OA vary between cohorts. We aimed to provide recommendations for combining knee and hip OA data in extant and future population cohort studies, in order to ...

Methodological aspects of the 1993 Pelotas (Brazil) Birth Cohort Study

Science.gov (United States)

Victora, Cesar Gomes; Araújo, Cora Luiza Pavin; Menezes, Ana Maria Batista; Hallal, Pedro Curi; Vieira, Maria de Fátima; Neutzling, Marilda Borges; Gonçalves, Helen; Valle, Neiva Cristina; Lima, Rosangela Costa; Anselmi, Luciana; Behague, Dominique; Gigante, Denise Petrucci; Barros, Fernando Celso

2010-01-01

This paper describes the main methodological aspects of a cohort study, with emphasis on its recent phases, which may be relevant to investigators planning to carry out similar studies. In 1993, a population based study was launched in Pelotas, Southern Brazil. All 5,249 newborns delivered in the city’s hospitals were enrolled, and sub-samples were visited at the ages of one, three and six months and of one and four years. In 2004-5 it was possible to trace 87.5% of the cohort at the age of 10-12 years. Sub-studies are addressing issues related to oral health, psychological development and mental health, body composition, and ethnography. Birth cohort studies are essential for investigating the early determinants of adult disease and nutritional status, yet few such studies are available from low and middle-income countries where these determinants may differ from those documented in more developed settings. PMID:16410981

Time-courses of lung function and respiratory muscle pressure generating capacity after spinal cord injury : a prospective cohort study

NARCIS (Netherlands)

Mueller, Gabi; de Groot, Sonja; van der Woude, Lucas; Hopman, Maria T E

OBJECTIVE: To investigate the time-courses of lung function and respiratory muscle pressure generating capacity after spinal cord injury. DESIGN: Multi-centre, prospective cohort study. SUBJECTS: One hundred and nine subjects with recent, motor complete spinal cord injury. METHODS: Lung function and

Possibilities and considerations when merging dietary data from the world's two largest pregnancy cohorts: the Danish National Birth Cohort and the Norwegian Mother and Child Cohort Study.

Science.gov (United States)

Olsen, Sjurdur F; Birgisdottir, Bryndis Eva; Halldorsson, Thorhallur I; Brantsaeter, Anne Lise; Haugen, Margaretha; Torjusen, Hanne; Petersen, Sesilje B; Strøm, Marin; Meltzer, Helle Margrete

2014-11-01

To elucidate the research possibilities when merging data on maternal diet from the Danish National Birth Cohort (DNBC) and the Norwegian Mother and Child Cohort Study (MoBa), through comparison of (i) the methodology used for dietary assessment and (ii) the estimated intake of selected food groups in the two cohorts. Qualitative and quantitative comparison of the two dietary databases. Two national prospective pregnancy cohorts. Denmark, Norway. Comparison of food intake using food frequency questionnaires (FFQs). The FFQs had overlapping time windows and a majority of the questions in the two FFQs were comparable. Calculation principles shared similar features, including the software used and use of global questions to calibrate intakes of different food groups. A total of 63 food groups were defined that could be compared across the two cohorts; these were further aggregated down to 31 broader groups. A comparison of food intakes (grams/d) showed 39, 74 and 141% lower daily intakes of fish, potatoes and rice, respectively, in DNBC vs. MoBa and 39, 54 and 65% higher daily intakes of milk, butter and potatoes in DNBC vs. MoBa. For most other food groups, differences in consumption data were below 20%. The two FFQs are to a large extent compatible and substantial differences in dietary habits were observed between the two cohorts. This may strengthen studies using pooled analysis to examine diet-disease relations. This is a conclusion of great importance given the colossal and costly task involved to establish each of these two cohorts. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

Representativeness of the LifeLines Cohort Study

NARCIS (Netherlands)

Klijs, B.; Scholtens, S.; Mandemakers, J.J.; Snieder, H.; Stolk, R.P.; Smidt, N.

2015-01-01

Background LifeLines is a large prospective population-based three generation cohort study in the north of the Netherlands. Different recruitment strategies were adopted: recruitment of an index population via general practitioners, subsequent inclusion of their family members, and online

A Canadian naturalistic study of a community-based cohort treated for bipolar disorder

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Chandresena Ranjith

2010-03-01

Full Text Available Abstract Background Bipolar illness is associated with significant psychosocial morbidity and health resource utilization. Second generation antipsychotics, used alone or in combination with mood stabilizers are effective in treating acute mania in community settings. This study was designed to compare the change in clinical parameters and resource utilization at one month in a group of patients who required treatment intervention for exacerbation of mania. The clinical response at one year was also evaluated. Methods 496 patients were enrolled at 75 psychiatric practices across Canada. The Olanzapine cohort (n = 287 included patients who had olanzapine added to their medication regimen or the dose of olanzapine increased. The Other cohort (n = 209 had a medication other than olanzapine added or the dose adjusted. Changes from baseline in the Young Mania Rating Scale (YMRS, Montgomery Asberg Depression Rating Scale, Beck Anxiety Inventory and SF-12 Health Survey were compared at one month using ANCOVA. Categorical variables at one month for health resource utilization, employment status, abuse/dependency, and the number of suicide attempts were compared using Fisher's Exact test. Patients were followed for one year and a subgroup was evaluated. Results At one month, patients in the Olanzapine cohort recorded a mean reduction in the YMRS of 11.5, significantly greater than the mean reduction in the Other cohort of 9.7 (ANCOVA P = 0.002. The Olanzapine cohort was significantly improved compared to the Other cohort on the scales for depression and anxiety and did not experience the deterioration in physical functioning seen in the Other cohort. No significant differences were detected in health-related quality-of-life measures, employment status, drug abuse/dependency, number of suicide attempts, mental functioning, emergency room visits or inpatient psychiatric hospitalizations. In a subgroup treated for 12 months with a single second generation

Developmental outcome at 18 and 24 months of age in very preterm children: a cohort study from 1996 to 1997

NARCIS (Netherlands)

Stoelhorst, Gerlinde M. S. J.; Rijken, Monique; Martens, Shirley E.; van Zwieten, Paul H. T.; Feenstra, J.; Zwinderman, Aeilko H.; Wit, Jan Maarten; Veen, Sylvia

2003-01-01

Objective: To determine the effect of prematurity (gestational age (GA) <32 weeks) on developmental outcome at the corrected age of 18 and 24 months in a regionally defined, prospective cohort study. Study design: The Leiden Follow-Up Project on Prematurity (LFUPP) includes all liveborn infants <32

Cardiovascular disease in patients with osteogenesis imperfecta — a nationwide, register-based cohort study

OpenAIRE

Folkestad, Lars; Hald, Jannie Dahl; Gram, Jeppe; Langdahl, Bente L.; Hermann, Anne Pernille; Diederichsen, Axel CP; Abrahamsen, Bo; Brixen, Kim

2016-01-01

BACKGROUND: Osteogenesis imperfecta (OI) is a hereditary connective tissue disease often due to mutations in genes coding for type 1 collagen. Collagen type 1 is important in the development of the heart and vasculature. Little is known about the risk of cardiovascular disease (CVD) in OI.OBJECTIVE: To investigate the risk of symptomatic CVD in OI.DESIGN: A Danish nationwide, population-based and register-based longitudinal open cohort study.PARTICIPANTS: All patients registered with the diag...

Extent and Determinants of Error in Doctors' Prognoses in Terminally Ill Patients: Prospective Cohort Study

OpenAIRE

Lamont, Elizabeth; Christakis, Nicholas

2000-01-01

Objective: To describe doctors' prognostic accuracy in terminally ill patients and to evaluate the determinants of that accuracy. Design: Prospective cohort study. Setting: Five outpatient hospice programmes in Chicago. Participants: 343 doctors provided survival estimates for 468 terminally ill patients at the time of hospice referral. Main outcome measures: Patients' estimated and actual survival. Results: Median survival was 24 days. Only 20% (92/468) of predictions were acc...

Patient Decision Aids Improve Decision Quality and Patient Experience and Reduce Surgical Rates in Routine Orthopaedic Care: A Prospective Cohort Study.

Science.gov (United States)

Sepucha, Karen; Atlas, Steven J; Chang, Yuchiao; Dorrwachter, Janet; Freiberg, Andrew; Mangla, Mahima; Rubash, Harry E; Simmons, Leigh H; Cha, Thomas

2017-08-02

Patient decision aids are effective in randomized controlled trials, yet little is known about their impact in routine care. The purpose of this study was to examine whether decision aids increase shared decision-making when used in routine care. A prospective study was designed to evaluate the impact of a quality improvement project to increase the use of decision aids for patients with hip or knee osteoarthritis, lumbar disc herniation, or lumbar spinal stenosis. A usual care cohort was enrolled before the quality improvement project and an intervention cohort was enrolled after the project. Participants were surveyed 1 week after a specialist visit, and surgical status was collected at 6 months. Regression analyses adjusted for clustering of patients within clinicians and examined the impact on knowledge, patient reports of shared decision-making in the visit, and surgical rates. With 550 surveys, the study had 80% to 90% power to detect a difference in these key outcomes. The response rates to the 1-week survey were 70.6% (324 of 459) for the usual care cohort and 70.2% (328 of 467) for the intervention cohort. There was no significant difference (p > 0.05) in any patient characteristic between the 2 cohorts. More patients received decision aids in the intervention cohort at 63.6% compared with the usual care cohort at 27.3% (p = 0.007). Decision aid use was associated with higher knowledge scores, with a mean difference of 18.7 points (95% confidence interval [CI], 11.4 to 26.1 points; p < 0.001) for the usual care cohort and 15.3 points (95% CI, 7.5 to 23.0 points; p = 0.002) for the intervention cohort. Patients reported more shared decision-making (p = 0.009) in the visit with their surgeon in the intervention cohort, with a mean Shared Decision-Making Process score (and standard deviation) of 66.9 ± 27.5 points, compared with the usual care cohort at 62.5 ± 28.6 points. The majority of patients received their preferred treatment, and this did not differ

A cohort study protocol to analyze the predisposing factors to common chronic non-communicable diseases in rural areas: Fasa Cohort Study

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Mojtaba Farjam

2016-10-01

Full Text Available Abstract Background Non-communicable diseases (NCDs have become the main causes of morbidity and mortality even in rural areas of many developing countries, including Iran. In view of this increased risk, Fasa Cohort Study (FACS has been established to assess the risk factors for NCDs with the ultimate goal of providing optimal risk calculators for Iranian population and finding grounds for interventions at the population level. Methods In a population-based cohort, at least 10,000 people within the age range of 35 to 70 years old from Sheshdeh, the suburb of Fasa city and its 24 satellite villages are being recruited. A detailed demographic, socioeconomic, anthropometric, nutrition, and medical history is obtained for each individual besides limited physical examinations and determination of physical activity and sleep patterns supplemented by body composition and electrocardiographic records. Routine laboratory assessments are done and a comprehensive biobank is compiled for future biological investigations. All data are stored online using a dedicated software. Discussion FACS enrolls the individuals from rural and little township areas to evaluate the health conditions and analyze the risk factors pertinent to major NCDs. This study will provide an evidence-based background for further national and international policies in preventive medicine. Yearly follow ups are designed to assess the health events in the participating population. It is believed that the results would construct a contemporary knowledge of Iranian high risk health characteristics and behaviors as well as the platform for further interventions of risk reduction in a typical Iranian population. Constantly probing for future advances in NCDs prevention and management, the accumulated database and biobank serves as a potential for state of the art research and international collaborations.

Motives for participating in a web-based nutrition cohort according to sociodemographic, lifestyle, and health characteristics: the NutriNet-Santé cohort study.

Science.gov (United States)

Méjean, Caroline; Szabo de Edelenyi, Fabien; Touvier, Mathilde; Kesse-Guyot, Emmanuelle; Julia, Chantal; Andreeva, Valentina A; Hercberg, Serge

2014-08-07

In traditional epidemiological studies, participants are likely motivated by perceived benefits, feelings of accomplishment, and belonging. No study has explored motives for participation in a Web-based cohort and the associated participant characteristics, although such information is useful for enhancing recruitment and improving cohort retention. We aimed to evaluate the relationships between motives for participation and sociodemographic, health, and lifestyle characteristics of participants in the NutriNet-Santé Web-based cohort, designed to identify nutritional risk or protective factors for chronic diseases. The motives for participation were assessed using a specifically developed questionnaire administered approximately 2 years after baseline. A total of 6352 completed the motives questionnaire (43.34%, 6352/15,000 randomly invited cohort participants). We studied the associations between motives (dependent variables) and individual characteristics with multivariate multinomial logistic regression models providing odds ratios and 95% confidence intervals. In total, 46.45% (2951/6352) of participants reported that they would not have enrolled if the study had not been conducted on the Internet, whereas 28.75% (1826/6352) were not sure. Men (OR 1.21, 95% CI 1.04-1.42), individuals aged 26-35 years (OR 1.51, 95% CI 1.20-1.91), and obese participants (OR 1.30, 95% CI 1.02-1.65) were more inclined to be motivated by the Internet aspect. Compared with younger adults and managerial staff, individuals >55 years (OR 0.60, 95% CI 0.48-0.45) and employees/manual workers were less likely motivated by the Internet aspect (OR 0.77, 95% CI 0.63-0.92). Regarding reasons for participation, 61.37% (3898/6352) reported participating to help advance public health research on chronic disease prevention; 22.24% (1413/6352) to help advance nutrition-focused research; 6.89% (438/6352) in response to the call from the media, after being encouraged by a close friend/associate, or

A cohort study of the recovery of health and wellbeing following colorectal cancer (CREW study: protocol paper

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Fenlon Deborah

2012-04-01

Full Text Available Abstract Background The number of people surviving colorectal cancer has doubled in recent years. While much of the literature suggests that most people return to near pre-diagnosis status following surgery for colorectal cancer, this literature has largely focused on physical side effects. Longitudinal studies in colorectal cancer have either been small scale or taken a narrow focus on recovery after surgery. There is a need for a comprehensive, long-term study exploring all aspects of health and wellbeing in colorectal cancer patients. The aim of this study is to establish the natural history of health and wellbeing in people who have been treated for colorectal cancer. People have different dispositions, supports and resources, likely resulting in individual differences in restoration of health and wellbeing. The protocol described in this paper is of a study which will identify who is most at risk of problems, assess how quickly people return to a state of subjective health and wellbeing, and will measure factors which influence the course of recovery. Methods/design This is a prospective, longitudinal cohort study following 1000 people with colorectal cancer over a period of two years, recruiting from 30 NHS cancer treatment centres across the UK. Questionnaires will be administered prior to surgery, and 3, 9, 15 and 24 months after surgery, with the potential to return to this cohort to explore on-going issues related to recovery after cancer. Discussion Outcomes will help inform health care providers about what helps or hinders rapid and effective recovery from cancer, and identify areas for intervention development to aid this process. Once established the cohort can be followed up for longer periods and be approached to participate in related projects as appropriate and subject to funding.

The Pelotas birth cohort study, Rio Grande do Sul, Brazil, 1982-2001

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Victora Cesar G.

2003-01-01

Full Text Available Given the growing recognition of the importance of the life course approach for the determination of chronic diseases, birth cohort studies are becoming increasingly important. This paper describes the methods used in the 1982 Pelotas (Brazil birth cohort study, one of the largest and longest studies of this type in developing countries. All 5,914 hospital births occurring in Pelotas in 1982 (over 99% of all deliveries were studied prospectively. The main stages of the study took place in 1983, 1984, 1986, 1995, 1997, 2000, and 2001. More than two thousand variables are available for each subject who participated in all stages of the study. Recent phases of the study included the examination of 2,250 males when presenting for the army recruitment exam in 2000, the study of a 27% sample of men and women in 2001 through household visits, and the study of over 400 children born to the cohort women. Follow-up rates in the recent stages of the cohort were 78.9% for the army examination and 69.0% for the household visits. Ethnographic and oral health studies were conducted in sub-samples. Some recent results on blood pressure, adolescent pregnancy, and asthma are presented as examples of utilization of the data. Suggestions on lessons learned for other cohort studies are proposed.

The Pelotas Birth Cohort Study, Rio Grande do Sul, Brazil, 1982-2001

Science.gov (United States)

2010-01-01

Given the growing recognition of the importance of the life course approach for the determination of chronic diseases, birth cohort studies are becoming increasingly important. This paper describes the methods used in the 1982 Pelotas (Brazil) birth cohort study, one of the largest and longest studies of this type in developing countries. All 5,914 hospital births occurring in Pelotas in 1982 (over 99% of all deliveries) were studied prospectively. The main stages of the study took place in 1983, 1984, 1986, 1995, 1997, 2000, and 2001. More than two thousand variables are available for each subject who participated in all stages of the study. Recent phases of the study included the examination of 2,250 males when presenting for the army recruitment exam in 2000, the study of a 27% sample of men and women in 2001 through household visits, and the study of over 400 children born to the cohort women. Follow-up rates in the recent stages of the cohort were 78.9% for the army examination and 69.0% for the household visits. Ethnographic and oral health studies were conducted in sub-samples. Some recent results on blood pressure, adolescent pregnancy, and asthma are presented as examples of utilization of the data. Suggestions on lessons learned for other cohort studies are proposed. PMID:14666206

Rationale and design of a multicenter echocardiographic study to assess the relationship between cardiac structure and function and heart failure risk in a biracial cohort of community-dwelling elderly persons: the Atherosclerosis Risk in Communities study.

Science.gov (United States)

Shah, Amil M; Cheng, Susan; Skali, Hicham; Wu, Justina; Mangion, Judy R; Kitzman, Dalane; Matsushita, Kunihiro; Konety, Suma; Butler, Kenneth R; Fox, Ervin R; Cook, Nakela; Ni, Hanyu; Coresh, Josef; Mosley, Thomas H; Heiss, Gerardo; Folsom, Aaron R; Solomon, Scott D

2014-01-01

Heart failure is an important public health concern, particularly among persons>65 years of age. Women and blacks are critically understudied populations that carry a sizeable portion of the heart failure burden. Limited normative and prognostic data exist on measures of cardiac structure, diastolic function, and novel measures of systolic deformation in older adults living in the community. The Atherosclerosis Risk in Communities (ARIC) study is a large, predominantly biracial, National Heart, Lung, and Blood Institute-sponsored epidemiological cohort study. Between 2011 and 2013, ≈6000 surviving participants, now in their seventh to ninth decade of life, are expected to return for a fifth study visit during which comprehensive 2-dimensional, Doppler, tissue Doppler, and speckle-tracking echocardiography will be performed uniformly in all cohort clinic visit participants. The following objectives will be addressed: (1) to characterize cardiac structural and functional abnormalities among the elderly and to determine how they differ by sex and race/ethnicity, (2) to determine the relationship between ventricular and vascular abnormalities, and (3) to prospectively examine the extent to which these noninvasive measures associate with incident heart failure. We describe the design, imaging acquisition and analysis methods, and quality assurance metrics for echocardiography in visit 5 of the ARIC cohort. A better understanding of the differences in cardiac structure and function through the spectrum of heart failure stages in elderly persons generally, and between sexes and racial/ethnic groups specifically, will deepen our understanding of the pathophysiology driving heart failure progression in these at-risk populations and may inform novel prevention or therapeutic strategies.

Cohorts based on decade of death: no evidence for secular trends favoring later cohorts in cognitive aging and terminal decline in the AHEAD study.

Science.gov (United States)

Hülür, Gizem; Infurna, Frank J; Ram, Nilam; Gerstorf, Denis

2013-03-01

Studies of birth-year cohorts examined over the same age range often report secular trends favoring later-born cohorts, who are cognitively fitter and show less steep cognitive declines than earlier-born cohorts. However, there is initial evidence that those advantages of later-born cohorts do not carry into the last years of life, suggesting that pervasive mortality-related processes minimize differences that were apparent earlier in life. Elaborating this work from an alternative perspective on cohort differences, we compared rates of cognitive aging and terminal decline in episodic memory between cohorts based on the year participants had died, earlier (between 1993 and 1999) or later in historical time (between 2000 and 2010). Specifically, we compared trajectories of cognitive decline in 2 death-year cohorts of participants in the Asset and Health Dynamics Among the Oldest Old study that were matched on age at death and education and controlled for a variety of additional covariates. Results revealed little evidence of secular trends favoring later cohorts. To the contrary, the cohort that died in the 2000s showed a less favorable trajectory of age-related memory decline than the cohort that died in the 1990s. In examinations of change in relation to time to death, the cohort dying in the 2000s experienced even steeper terminal declines than the cohort dying in the 1990s. We suggest that secular increases in "manufacturing" survival may exacerbate age- and mortality-related cognitive declines among the oldest old.

Injuries in Professional Male Soccer Players in the Netherlands: A Prospective Cohort Study

NARCIS (Netherlands)

Stubbe, J.H.; Beijsterveldt, A.M. van; Knaap, S. van der; Stege, J.; Verhagen, E.; Mechelen, W. van; Backx, F.J.G.

2015-01-01

Context : Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective : To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design : Cohort

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

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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.

Birth cohort differences in cardiovascular risk factors in a Brazilian population of older elderly: the Bambuí cohort study of aging (1997 and 2008

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Marco Polo Dias Freitas

2011-01-01

Full Text Available The aim of this study was to investigate whether cohort differences exist in the prevalence of cardiovascular risk factors among older elderly from the Bambuí Cohort Study of Aging. Participants were those aged 71-81 years at two points in time a decade apart: 457 in 1997 (earlier cohort and 553 in 2008 (recent cohort. The prevalence of hypertension (PR = 1.27; 95%CI: 1.19-1.36 and of diabetes mellitus (PR = 1.39; 95%CI: 1.06-1.83 was higher in the recent cohort compared to the earlier one, regardless of sex. The recent cohort had a lower prevalence of smoking (PR = 0.58; 95%CI: 0.42-0.80, and lower total cholesterol/HDL cholesterol ratio level (PR = 0.85; 95%CI: 0.80-0.89. There was a 136% increase in the pharmacologic treatment of diabetes and a 56% increase in pharmacologic management of hypertension in 2008 in comparison with 1997. Overall, the number of cardiovascular risk factors in the recent cohort remained similar to that of the early cohort.

A prospective cohort study to investigate cost-minimisation, of Traditional open, open fAst track recovery and laParoscopic fASt track multimodal management, for surgical patients with colon carcinomas (TAPAS study

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van Duivendijk Peter

2010-06-01

Full Text Available Abstract Background The present developments in colon surgery are characterized by two innovations: the introduction of the laparoscopic operation technique and fast recovery programs such as the Enhanced Recovery After Surgery (ERAS recovery program. The Tapas-study was conceived to determine which of the three treatment programs: open conventional surgery, open 'ERAS' surgery or laparoscopic 'ERAS' surgery for patients with colon carcinomas is most cost minimizing? Method/design The Tapas-study is a three-arm multicenter prospective cohort study. All patients with colon carcinoma, eligible for surgical treatment within the study period in four general teaching hospitals and one university hospital will be included. This design produces three cohorts: Conventional open surgery is the control exposure (cohort 1. Open surgery with ERAS recovery (cohort 2 and laparoscopic surgery with ERAS recovery (cohort 3 are the alternative exposures. Three separate time periods are used in order to prevent attrition bias. Primary outcome parameters are the two main cost factors: direct medical costs (real cost price calculation and the indirect non medical costs (friction method. Secondary outcome parameters are mortality, complications, surgical-oncological resection margins, hospital stay, readmission rates, time back to work/recovery, health status and quality of life. Based on an estimated difference in direct medical costs (highest cost factor of 38% between open and laparoscopic surgery (alfa = 0.01, beta = 0.05, a group size of 3×40 = 120 patients is calculated. Discussion The Tapas-study is three-arm multicenter cohort study that will provide a cost evaluation of three treatment programs for patients with colon carcinoma, which may serve as a guideline for choice of treatment and investment strategies in hospitals. Trial registration ISRCTN44649165.

Employment Trajectories After Spinal Cord Injury : Results From a 5-Year Prospective Cohort Study

NARCIS (Netherlands)

Ferdiana, Astri; Post, Marcel W.; Hoekstra, Trynke; van der Woude, Luccas H.; van der Klink, Jac J.; Bultmann, Ute

Objectives: To identify different employment trajectories in individuals with spinal cord injury (SCI) after discharge from initial rehabilitation and to determine predictors of different trajectories from demographic, injury, functional, and psychological characteristics. Design: Prospective cohort

Perceptions of visual communication design education in higher education in Ireland: A multi-case study from the design industry, institutes and graduates perspectives

OpenAIRE

DOWLING, FIONA

2018-01-01

APPROVED ?Use your own vision and mentality in order to form design decisions + Don?t believe your professor? Annelys de Vet ? (Kiosoglou & Frank, Ed. 2013., p 34). The aim of the study was to evaluate and construct an explanation behind the currency that higher education degrees in design enjoy in Ireland. The Visual Communication (VC) design discipline at Bachelors (BA) level accounted for the greatest cohort of students leaving design HE in Ireland in the 1990s. This grap...

Milk intake and risk of mortality and fractures in women and men: cohort studies.

Science.gov (United States)

Michaëlsson, Karl; Wolk, Alicja; Langenskiöld, Sophie; Basu, Samar; Warensjö Lemming, Eva; Melhus, Håkan; Byberg, Liisa

2014-10-28

To examine whether high milk consumption is associated with mortality and fractures in women and men. Cohort studies. Three counties in central Sweden. Two large Swedish cohorts, one with 61,433 women (39-74 years at baseline 1987-90) and one with 45,339 men (45-79 years at baseline 1997), were administered food frequency questionnaires. The women responded to a second food frequency questionnaire in 1997. Multivariable survival models were applied to determine the association between milk consumption and time to mortality or fracture. During a mean follow-up of 20.1 years, 15,541 women died and 17,252 had a fracture, of whom 4259 had a hip fracture. In the male cohort with a mean follow-up of 11.2 years, 10,112 men died and 5066 had a fracture, with 1166 hip fracture cases. In women the adjusted mortality hazard ratio for three or more glasses of milk a day compared with less than one glass a day was 1.93 (95% confidence interval 1.80 to 2.06). For every glass of milk, the adjusted hazard ratio of all cause mortality was 1.15 (1.13 to 1.17) in women and 1.03 (1.01 to 1.04) in men. For every glass of milk in women no reduction was observed in fracture risk with higher milk consumption for any fracture (1.02, 1.00 to 1.04) or for hip fracture (1.09, 1.05 to 1.13). The corresponding adjusted hazard ratios in men were 1.01 (0.99 to 1.03) and 1.03 (0.99 to 1.07). In subsamples of two additional cohorts, one in males and one in females, a positive association was seen between milk intake and both urine 8-iso-PGF2α (a biomarker of oxidative stress) and serum interleukin 6 (a main inflammatory biomarker). High milk intake was associated with higher mortality in one cohort of women and in another cohort of men, and with higher fracture incidence in women. Given the observational study designs with the inherent possibility of residual confounding and reverse causation phenomena, a cautious interpretation of the results is recommended. © Michaëlsson et al 2014.

A patient cohort on long-term sequelae of sepsis survivors: study protocol of the Mid-German Sepsis Cohort.

Science.gov (United States)

Scherag, André; Hartog, Christiane S; Fleischmann, Carolin; Ouart, Dominique; Hoffmann, Franziska; König, Christian; Kesselmeier, Miriam; Fiedler, Sandra; Philipp, Monique; Braune, Anke; Eichhorn, Cornelia; Gampe, Christin; Romeike, Heike; Reinhart, Konrad

2017-08-23

An increasing number of patients survive sepsis; however, we lack valid data on the long-term impact on morbidity from prospective observational studies. Therefore, we designed an observational cohort to quantify mid-term and long-term functional disabilities after intensive care unit (ICU)-treated sepsis. Ultimately, findings for the Mid-German Sepsis Cohort (MSC) will serve as basis for the implementation of follow-up structures for patients with sepsis and help to increase quality of care for sepsis survivors. All patients surviving ICU-treated sepsis are eligible and are recruited from five study centres in Germany (acute care hospital setting in Jena, Halle/Saale, Leipzig, Bad Berka, Erfurt; large long-term acute care hospital and rehabilitation setting in Klinik Bavaria Kreischa). Screening is performed by trained study nurses. Data are collected on ICU management of sepsis. On written informed consent provided by patients or proxies, follow-up is carried out by trained research staff at 3, 6 and 12 months and yearly thereafter. The primary outcome is functional disability as assessed by (instrumental) activities of daily living. Other outcomes cover domains like mortality, cognitive, emotional and physical impairment, and resource use. The estimated sample size of 3000 ICU survivors is calculated to allow detection of relevant changes in the primary outcome in sepsis survivors longitudinally. The study is conducted according to the current version of the Declaration of Helsinki and has been approved by four local/federal responsible institutional ethics committees and by the respective federal data protection commissioners. Results of MSC will be fed back to the patients and published in peer-reviewed journals. German Clinical Trials Registry DRKS00010050. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The role of birth cohorts in studies of adult health: the New York women's birth cohort.

Science.gov (United States)

Terry, Mary Beth; Flom, Julie; Tehranifar, Parisa; Susser, Ezra

2009-09-01

Epidemiological studies investigating associations between early life factors and adult health are often limited to studying exposures that can be reliably recalled in adulthood or obtained from existing medical records. There are few US studies with detailed data on the pre- and postnatal environment whose study populations are now in adulthood; one exception is the Collaborative Perinatal Project (CPP). We contacted former female participants of the New York site of the CPP who were born from 1959 to 1963 and were prospectively followed for 7 years to examine whether the pre- and postnatal environment is associated with adult health in women 40 years after birth. The New York CPP cohort is particularly diverse; at enrolment, the race/ethnicity distribution of mothers was approximately 30% White, 40% Black and 30% Puerto Rican. Of the 841 eligible women, we successfully traced 375 women (45%) and enrolled 262 women (70% of those traced). Baseline data were available for all eligible women, and we compared those who participated with the remaining cohort (n = 579). Higher family socio-economic status at age 7, availability of maternal social security number, and White race/ethnicity were statistically significantly associated with a higher probability of tracing. Of those traced, race/ethnicity was associated with participation, with Blacks and Puerto Ricans less likely to participate than Whites (OR = 0.5, 95% CI 0.3, 0.8, and OR = 0.5, 95% CI 0.3, 1.0, respectively). In addition, higher weight at 7 years was associated with lower participation (OR = 0.95, 95% CI 0.92, 0.99), but this association was observed only among the non-White participants. None of the other maternal characteristics, infant or early childhood growth measures was associated with participation or with tracing, either overall or within each racial/ethnic subgroup. Daughters' recall of early life factors such as pre-eclampsia (sensitivity = 24%) and birthweight were generally poor, with the

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...

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

Utilizing harmonization and common surveillance methods to consolidate 4 cohorts: the Western Alaska Tribal Collaborative for Health (WATCH study

Directory of Open Access Journals (Sweden)

Kathryn R. Koller

2013-05-01

Full Text Available Background. According to health status reports, chronic disease prevalence appears to be rising in western Alaska Native (AN people, and accurate population-based data are needed. Four cohort studies of western AN people were conducted in the Norton Sound and Yukon-Kuskokwim regions, but none have been large enough to allow reliable estimates of rates of chronic diseases and evaluate their risk factors. Objective. In this article, the methods used to combine 4 major cohort studies of rural western AN people are described and the benefits and challenges encountered in combining data and standardizing surveillance methods for these studies are discussed. Design. Tribal permission was obtained for each cohort study and the consolidated study. Data from baseline exams were directly combined or harmonized into new variables. Common surveillance methods were developed and implemented to identify incidence and risk factors for cardiovascular disease (CVD events and type 2 diabetes. Results. A cohort of 4,569 western AN participants (2,116 men and 2,453 women, aged 18–95 years, was established to study CVD and diabetes prevalence. Prospective surveillance data over an average 6.7-year follow-up can now be used to study CVD and diabetes incidence and associated risk factors in a subset of 2,754 western AN participants (1,218 men and 1,536 women who consented to initial surveillance. Conclusions. The combined cohort provides statistical power to examine incidence rates and risk factors for CVD and diabetes and allows for analyses by geographic region. The data can be used to develop intervention programmes in these populations and others.

A prospective study of symptoms, function, and medication use during acute illness in nursing home residents: design, rationale and cohort description

Directory of Open Access Journals (Sweden)

Liu Sophia

2010-07-01

incidence of 1.5 (SD 2.0 episodes per resident per year; 74% were managed in the nursing home and 26% managed in the acute care setting. Conclusion In this report, we describe the conceptual model and methods of designing a longitudinal cohort to measure acute illness patterns and symptoms among nursing home residents, and describe the characteristics of our cohort at baseline. In our planned analysis, we will further estimate the effect of the use and interruption of medications on withdrawal and relapse symptoms and illness outcomes.

Development of a Web Portal for Physical Activity and Symptom Tracking in Oncology Patients: Protocol for a Prospective Cohort Study.

Science.gov (United States)

Marthick, Michael; Dhillon, Haryana M; Alison, Jennifer A; Cheema, Birinder S; Shaw, Tim

2018-05-15

Significant benefits accrue from increasing physical activity levels in people with a history of cancer. Physical activity levels can be increased using behavioral change interventions in this population. Access to Web portals and provision of activity monitors to provide feedback may support behavior change by encouraging patient engagement in physical therapy. The Web portal evaluated in this study will provide a system to monitor physical activity and sleep, for use by both clinician and patient, along with symptom and health-related quality of life tracking capabilities. The aim of this study was to outline a protocol for a feasibility study focused on a Web-based portal that provides activity monitoring and personalized messaging to increase physical activity in people with cancer. Using a longitudinal cohort design, people with cancer will be serially allocated to 3 intervention cohorts of 20 participants each and followed for 10 weeks. Cohort 1 will be provided a wearable activity monitor and access to a Web-based portal. Cohort 2 will receive the same content as Cohort 1 and in addition will receive a weekly activity summary message. Cohort 3 will receive the same content as Cohorts 1 and 2 and in addition will receive a personalized weekly coaching message. Feasibility of the use of the portal is the primary outcome. Results are expected in early 2018. Outcome measures will include goal attainment and completion rate. This study will provide information about the feasibility of investigating eHealth initiatives to promote physical activity in people with cancer. RR1-10.2196/9586. ©Michael Marthick, Haryana M Dhillon, Jennifer A Alison, Birinder S Cheema, Tim Shaw. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 15.05.2018.

Physical exercise during pregnancy and fetal growth measures: a study within the Danish National Birth Cohort

DEFF Research Database (Denmark)

Juhl, Mette; Olsen, Jørn; Andersen, Per Kragh

2010-01-01

OBJECTIVE: The objective of the study was to examine the association between physical exercise during pregnancy and fetal growth measures. STUDY DESIGN: Data on 79,692 liveborn singletons from the Danish National Birth Cohort were collected between 1996 and 2002. Mean differences in birthweight, ...... effects on fetal growth measures related to exercise apart from a modest decreased risk of small- and large-for-gestational-age infants. These findings do not speak against advising pregnant women to be physically active during pregnancy....

Rationale and study design of the Japan environment and children’s study (JECS)

Science.gov (United States)

2014-01-01

Background There is global concern over significant threats from a wide variety of environmental hazards to which children face. Large-scale and long-term birth cohort studies are needed for better environmental management based on sound science. The primary objective of the Japan Environment and Children’s Study (JECS), a nation-wide birth cohort study that started its recruitment in January 2011, is to elucidate environmental factors that affect children’s health and development. Methods/Design Approximately 100,000 expecting mothers who live in designated study areas will be recruited over a 3-year period from January 2011. Participating children will be followed until they reach 13 years of age. Exposure to environmental factors will be assessed by chemical analyses of bio-specimens (blood, cord blood, urine, breast milk, and hair), household environment measurements, and computational simulations using monitoring data (e.g. ambient air quality monitoring) as well as questionnaires. JECS’ priority outcomes include reproduction/pregnancy complications, congenital anomalies, neuropsychiatric disorders, immune system disorders, and metabolic/endocrine system disorders. Genetic factors, socioeconomic status, and lifestyle factors will also be examined as covariates and potential confounders. To maximize representativeness, we adopted provider-mediated community-based recruitment. Discussion Through JECS, chemical substances to which children are exposed during the fetal stage or early childhood will be identified. The JECS results will be translated to better risk assessment and management to provide healthy environment for next generations. PMID:24410977

The Northern Norway mother-and-child contaminant cohort study: implementation, population characteristics and summary of dietary findings

Directory of Open Access Journals (Sweden)

Anna Sofía Veyhe

2012-05-01

Full Text Available Objectives. To describe the essential features of a new Northern Norway mother-and-child contaminant cohort study called MISA, including its rationale, content, implementation and selected findings (mostly dietary. Study design. Cross-sectional with longitudinal aspects. Methods. Five hundred and fifteen eligible women were enrolled in early pregnancy, with 391 completing the study protocol that included a self-administrated food frequency questionnaire (FFQ and donation of biological samples for contaminant analysis in the 2nd trimester, just after delivery, and 6 weeks postpartum. Macronutrient consumption was converted to energy intake, and the amounts of both macro- and micronutrients ingested were estimated. Some of the MISA findings were compared to data available in the Medical Birth Registry of Norway (MBRN. Results. Compared to all 2004–2006 mothers in Northern Norway, the study cohort women were about 2 years older and smoked less; on average, they had close to 16 years of education. Parity, gestational age and birth weight of the newborn were comparable as well. The estimated average dietary intake of 8.1 MJ per day was less than that recommended by the Nordic Nutritional Recommendations (NNR, but the intake of micronutrients per MJ complied. Conclusions. Although the final cohort sample size was less than targeted, the generally good comparisons observed between MBRN-registered information for the study cohort and dropouts suggest that this occurrence introduced minimal bias. The agreement of the observed demographic and clinical characteristics of the cohort women and newborns with all births in Northern Norway implied acceptable external validity. Also, the dietary findings aligned well with Norwegian national data and guidelines and other studies, as did the high prevalence of breastfeeding. The MISA database is considered suitable for exploring associations between contaminant exposure and diet, enhancing our knowledge of the

Neurological recovery in obstetric brachial plexus injuries: an historical cohort study

NARCIS (Netherlands)

Hoeksma, Agnes F.; ter Steeg, Anne Marie; Nelissen, Rob G. H. H.; van Ouwerkerk, Willem J. R.; Lankhorst, Gustaaf J.; de Jong, Bareld A.

2004-01-01

An historical cohort study was conducted to investigate the rate and extent of neurological recovery in obstetric brachial plexus injury (OBPI) and to identify possible prognostic factors in a cohort of children with OBPI from birth to 7 years. All children (n=56; 31 females, 25 males) with OBPI

Methadone and perinatal outcomes: a retrospective cohort study.

LENUS (Irish Health Repository)

Cleary, Brian J

2012-02-01

OBJECTIVE: The purpose of this study was to examine the relationship among methadone maintenance treatment, perinatal outcomes, and neonatal abstinence syndrome. STUDY DESIGN: This was a retrospective cohort study of 61,030 singleton births at a large maternity hospital from 2000-2007. RESULTS: There were 618 (1%) women on methadone at delivery. Methadone-exposed women were more likely to be younger, to book late for antenatal care, and to be smokers. Methadone exposure was associated with an increased risk of very preterm birth <32 weeks of gestation (adjusted odds ratio [aOR], 2.47; 95% confidence interval [CI], 1.40-4.34), being small for gestational age <10th percentile (aOR, 3.27; 95% CI, 2.49-4.28), admission to the neonatal unit (aOR, 9.14; 95% CI, 7.21-11.57), and diagnosis of a major congenital anomaly (aOR, 1.94; 95% CI, 1.10-3.43). There was a dose-response relationship between methadone and neonatal abstinence syndrome. CONCLUSION: Methadone exposure is associated with an increased risk of adverse perinatal outcomes, even when known adverse sociodemographic factors have been accounted for. Methadone dose at delivery is 1 of the determinants of neonatal abstinence syndrome.

Association of chronic obstructive pulmonary disease and hemorrhoids: A nationwide cohort study.

Science.gov (United States)

Lin, Lih-Hwa; Siu, Justin Ji-Yuen; Liao, Po-Chi; Chiang, Jen-Huai; Chou, Pei-Chi; Chen, Huey-Yi; Ho, Tsung-Jung; Tsai, Ming-Yen; Chen, Yung-Hsiang; Chen, Wen-Chi

2017-03-01

According to traditional Chinese medicine (TCM) theory, a specific physiological and pathological relationship exists between the lungs and the large intestine. The aim of this study is to delineate the association of chronic obstructive pulmonary disease (COPD) and hemorrhoids in order to verify the "interior-exterior" relationship between the lungs and the large intestine. A retrospective cohort study is conceived from the National Health Insurance Research Database, Taiwan. The 2 samples (COPD cohort and non-COPD cohort) were selected from the 2000 to 2003 beneficiaries of the NHI, representing patients age 20 and older in Taiwan, with the follow-up ending on December 31, 2011. The COPD cohort (n = 51,506) includes every patient newly diagnosed as having Chronic Obstructive Pulmonary Disease (COPD, ICD-9-CM: 490-492, 494, 496), who have made at least 2 confirmed visits to the hospital/clinic. The non-COPD cohort (n = 103,012) includes patients without COPD and is selected via a 1:2 (COPD: non-COPD) matching by age group (per 5 years), gender, and index date (diagnosis date of COPD for the COPD cohort). Compared with non-COPD cohorts, patients with COPD have a higher likelihood of having hemorrhoids and the age-, gender- and comorbidies-adjusted hazard ratio (HR) for hemorrhoids is 1.56 (95% confidence intervals [CI]:1.50-1.62). The adjusted HR of hemorrhoids for females is 0.79 (95% CI: 0.77-0.83), which is significantly less than that for males. The elderly groups, 40 to 59 years and aged 60 or above, have higher adjusted HRs than younger age groups (20-39 years), 1.19 (95% CI: 1.14-1.26), and 1.18 (95% CI: 1.12-1.24), respectively. Patients with COPD may have a higher likelihood to have hemorrhoids in this retrospective cohort study. This study verifies the fundamental theorem of TCM that there is a definite pathogenic association between the lungs and large intestine.

Setting up a cohort study in speech and language therapy: lessons from The UK Cleft Collective Speech and Language (CC-SL) study.

Science.gov (United States)

Wren, Yvonne; Humphries, Kerry; Stock, Nicola Marie; Rumsey, Nichola; Lewis, Sarah; Davies, Amy; Bennett, Rhiannon; Sandy, Jonathan

2018-05-01

Efforts to increase the evidence base in speech and language therapy are often limited by methodological factors that have restricted the strength of the evidence to the lower levels of the evidence hierarchy. Where higher graded studies, such as randomized controlled trials, have been carried out, it has sometimes been difficult to obtain sufficient power to detect a potential effect of intervention owing to small sample sizes or heterogeneity in the participants. With certain clinical groups such as cleft lip and palate, systematic reviews of intervention studies have shown that there is no robust evidence to support the efficacy of any one intervention protocol over another. To describe the setting up of an observational clinical cohort study and to present this as an alternative design for answering research questions relating to prevalence, risk factors and outcomes from intervention. The Cleft Collective Speech and Language (CC-SL) study is a national cohort study of children born with cleft palate. Working in partnership with regional clinical cleft centres, a sample size of over 600 children and 600 parents is being recruited and followed up from birth to age 5 years. Variables being collected include demographic, psychological, surgical, hearing, and speech and language data. The process of setting up the study has led to the creation of a unique, large-scale data set which is available for researchers to access now and in future. As well as exploring predictive factors, the data can be used to explore the impact of interventions in relation to individual differences. Findings from these investigations can be used to provide information on sample criteria and definitions of intervention and dosage which can be used in future trials. The observational cohort study is a useful alternative design to explore questions around prevalence, risk factors and intervention for clinical groups where robust research data are not yet available. Findings from such a

Towards non-conventional methods of designing register-based epidemiological studies: An application to pediatric research.

Science.gov (United States)

Gong, Tong; Brew, Bronwyn; Sjölander, Arvid; Almqvist, Catarina

2017-07-01

Various epidemiological designs have been applied to investigate the causes and consequences of fetal growth restriction in register-based observational studies. This review seeks to provide an overview of several conventional designs, including cohort, case-control and more recently applied non-conventional designs such as family-based designs. We also discuss some practical points regarding the application and interpretation of family-based designs. Definitions of each design, the study population, the exposure and the outcome measures are briefly summarised. Examples of study designs are taken from the field of low birth-weight research for illustrative purposes. Also examined are relative advantages and disadvantages of each design in terms of assumptions, potential selection and information bias, confounding and generalisability. Kinship data linkage, statistical models and result interpretation are discussed specific to family-based designs. When all information is retrieved from registers, there is no evident preference of the case-control design over the cohort design to estimate odds ratios. All conventional designs included in the review are prone to bias, particularly due to residual confounding. Family-based designs are able to reduce such bias and strengthen causal inference. In the field of low birth-weight research, family-based designs have been able to confirm a negative association not confounded by genetic or shared environmental factors between low birth weight and the risk of asthma. We conclude that there is a broader need for family-based design in observational research as evidenced by the meaningful contributions to the understanding of the potential causal association between low birth weight and subsequent outcomes.

Family history of psychiatric illness as a risk factor for schizoaffective disorder: a Danish register-based cohort study

DEFF Research Database (Denmark)

Laursen, Thomas Munk; Labouriau, Rodrigo; Licht, Rasmus W

2005-01-01

BACKGROUND: Schizoaffective disorder may be related to both schizophrenia and bipolar disorders, but no population-based studies, to our knowledge, have investigated this association in families. OBJECTIVES: To determine whether a psychiatric history of schizoaffective disorder, bipolar disorder......, or schizophrenia among parents and siblings is a risk factor for developing a schizoaffective disorder, and whether a specific pattern of family history of psychiatric illness exists in persons with schizoaffective disorder compared with persons with bipolar disorder or schizophrenia. DESIGN: Register-based cohort...... study. SETTING: Denmark. COHORT: The 2.4 million persons born in Denmark after 1952. MAIN OUTCOME MEASURES: Relative risks of the 3 illnesses estimated by Poisson regression. RESULTS: In total, 1925 persons had a schizoaffective disorder, 3721 had a bipolar disorder, and 12 501 had schizophrenia...

Longitudinal relationship between wheelchair exercise capacity and life satisfaction in patients with spinal cord injury : A cohort study in the Netherlands

NARCIS (Netherlands)

van Koppenhagen, Casper Floris; Post, Marcel; de Groot, Sonja; van Leeuwen, Christel; van Asbeck, Floris; Stolwijk-Swüste, Janneke; van der Woude, Lucas; Lindeman, Eline

Objective: To examine the relationship between wheelchair exercise capacity and life satisfaction in persons with spinal cord injury from the start of active inpatient rehabilitation up to 5 years after discharge. Design: Prospective cohort study. Subjects: Persons with spinal cord injury, aged

Do antidepressants increase the risk of mania and bipolar disorder in people with depression? A retrospective electronic case register cohort study

NARCIS (Netherlands)

Patel, Rashmi; Reiss, Peter; Shetty, Hitesh; Broadbent, Matthew; Stewart, Robert; McGuire, Philip; Taylor, Matthew

2015-01-01

Objectives To investigate the association between antidepressant therapy and the later onset of mania/bipolar disorder. Design Retrospective cohort study using an anonymised electronic health record case register. Setting South London and Maudsley National Health Service (NHS) Trust (SLaM), a large

Outcomes of Zika virus infection during pregnancy: contributions to the debate on the efficiency of cohort studies.

Science.gov (United States)

Duarte, Elisabeth Carmen; Garcia, Leila Posenato; de Araújo, Wildo Navegantes; Velez, Maria P

2017-12-02

Zika infection during pregnancy (ZIKVP) is known to be associated with adverse outcomes. Studies on this matter involve both rare outcomes and rare exposures and methodological choices are not straightforward. Cohort studies will surely offer more robust evidences, but their efficiency must be enhanced. We aim to contribute to the debate on sample selection strategies in cohort studies to assess outcomes associated with ZKVP. A study can be statistically more efficient than another if its estimates are more accurate (precise and valid), even if the studies involve the same number of subjects. Sample size and specific design strategies can enhance or impair the statistical efficiency of a study, depending on how the subjects are distributed in subgroups pertinent to the analysis. In most ZIKVP cohort studies to date there is an a priori identification of the source population (pregnant women, regardless of their exposure status) which is then sampled or included in its entirety (census). Subsequently, the group of pregnant women is classified according to exposure (presence or absence of ZIKVP), respecting the exposed:unexposed ratio in the source population. We propose that the sample selection be done from the a priori identification of groups of pregnant women exposed and unexposed to ZIKVP. This method will allow for an oversampling (even 100%) of the pregnant women with ZKVP and a optimized sampling from the general population of pregnant women unexposed to ZIKVP, saving resources in the unexposed group and improving the expected number of incident cases (outcomes) overall. We hope that this proposal will broaden the methodological debate on the improvement of statistical power and protocol harmonization of cohort studies that aim to evaluate the association between Zika infection during pregnancy and outcomes for the offspring, as well as those with similar objectives.

The longitudinal urban cohort ageing study (LUCAS: study protocol and participation in the first decade

Directory of Open Access Journals (Sweden)

Dapp Ulrike

2012-07-01

Full Text Available Abstract Background We present concept, study protocol and selected baseline data of the Longitudinal Urban Cohort Ageing Study (LUCAS in Germany. LUCAS is a long-running cohort study of community-dwelling seniors complemented by specific studies of geriatric patients or diseases. Aims were to (1 Describe individual ageing trajectories in a metropolitan setting, documenting changes in functional status, the onset of frailty, disability and need of care; (2 Find determinants of healthy ageing; (3 Assess long-term effects of specific health promotion interventions; (4 Produce results for health care planning for fit, pre-frail, frail and disabled elderly persons; (5 Set up a framework for embedded studies to investigate various hypotheses in specific subgroups of elderly. Methods/Design In 2000, twenty-one general practitioners (GPs were recruited in the Hamburg metropolitan area; they generated lists of all their patients 60 years and older. Persons not terminally ill, without daily need of assistance or professional care were eligible. Of these, n = 3,326 (48 % agreed to participate and completed a small (baseline and an extensive health questionnaire (wave 1. In 2007/2008, a re-recruitment took place including 2,012 participants: 743 men, 1,269 women (647 deaths, 197 losses, 470 declined further participation. In 2009/2010 n = 1,627 returned the questionnaire (90 deaths, 47 losses, 248 declined further participation resulting in a good participation rate over ten years with limited and quantified dropouts. Presently, follow-up data from 2007/2008 (wave 2 and 2009/2010 (wave 3 are available. Data wave 4 is due in 2011/2012, and the project will be continued until 2013. Information on survival and need of nursing care was collected continuously and cross-checked against official records. We used Fisher’s exact test and t-tests. The study served repeatedly to evaluate health promotion interventions and concepts. Discussion LUCAS

Single Nucleotide Polymorphisms in IL1B and the Risk of Acute Coronary Syndrome: A Danish Case-Cohort Study

DEFF Research Database (Denmark)

Stegger, Jakob Gerhard; Schmidt, Erik Berg; Tjonneland, Anne

2012-01-01

Background: Interleukin-1B (IL-1B) is a key pro-inflammatory cytokine that has been associated with the development of atherosclerosis and myocardial infarction. However, the prospective associations between functional single nucleotide polymorphisms (SNPs) in IL1B and incident acute coronary...... and 234 women). All cases were validated by review of medical records, and information on covariates was collected by study technicians. The study was conducted according to a case-cohort study design including ACS cases and a sex-stratified sub cohort of 1663 participants drawn randomly from the entire...... IL1B haplotypes and risk factors, respectively. Conclusions/Significance: Genetic variation in the promoter region of IL1B may not be associated with incident ACS in men or women above the age of 50 years....

The rationale/design of the Guimarães/Vizela study: a multimodal population-based cohort study to determine global cardiovascular risk and disease.

Science.gov (United States)

Cunha, Pedro Guimarães; Cotter, Jorge; Oliveira, Pedro; Vila, Isabel; Sousa, Nuno

2014-06-01

Cardiovascular disease and dementia are growing medical and social problems in aging societies. Appropriate knowledge of cardiovascular disease and cognitive decline risk factors (RFs) are critical for global CVR health preventive intervention. Many epidemiological studies use case definition based on data collected/measured in a single visit, a fact that can overestimate prevalence rates and distant from clinical practice demanding criteria. Portugal displays an elevated stroke mortality rate. However, population's global CV risk characterization is limited, namely, considering traditional/nontraditional RF and new intermediate phenotypes of CV and renal disease. Association of hemodynamic variables (pulse wave velocity and central blood pressure) with global CVR stratification, cognitive performance, and kidney disease are practically inexistent at a dwelling population level. After reviewing published data, we designed a population-based cohort study to analyze the prevalence of these cardiovascular RFs and intermediate phenotypes, using random sampling of adult dwellers living in 2 adjacent cities. Strict definition of phenotypes was planned: subjects were observed twice, and several hemodynamic and other biological variables measured at least 3 months apart. Three thousand thirty-eight subjects were enrolled, and extensive data collection (including central and peripheral blood pressure, pulse wave velocity), sample processing, and biobank edification were carried out. One thousand forty-seven cognitive evaluations were performed. Seeking for CV risk reclassification, early identification of subjects at risk, and evidence of early vascular aging and cognitive and renal function decline, using the strict daily clinical practice criteria, will lead to better resource allocation in preventive measures at a population level.

The Argentina Premature Asthma and Respiratory Team (APART: objectives, design, and recruitment results of a prospective cohort study of viruses and wheezing in very low birth weight infants

Directory of Open Access Journals (Sweden)

Tatyana Plachco

2014-12-01

Full Text Available Background: Asthma and wheezing account for a substantial disease burden around the world. Very low birth weight (VLBW, <1500 grams infants are at an increased risk for the development of severe acute respiratory illness (ARI and recurrent wheeze/asthma. The role of respiratory viruses in asthma predisposition in premature infants is not well understood. Preliminary evidence suggests that infection with human rhinovirus (RV early in life may contribute to greater burden of asthma later in life. Methods: A prospective cohort study of premature VLBW infants from Buenos Aires, Argentina, was enrolled year-round during a three-year period in the neonatal intensive care unit and followed during every ARI and with monthly well visits during the first year of life. Longitudinal follow-up up until age five years is ongoing. Results: This report describes the objectives, design, and recruitment results of this prospective cohort. Two hundred and five patients were enrolled from August 2011 through January 2014, and follow-up is ongoing. A total of 319 ARI episodes were observed from August 2011 to July 2014, and 910 well visits occurred during this time period. Conclusions: The Argentina Premature Asthma and Respiratory Team (APART is a unique cohort consisting of over 200 patients and over 1200 specimens who have been and will continue to be followed intensively from NICU discharge to capture baseline risk factors and every ARI, with interceding well visits during the first year of life, as well as longitudinal follow-up to age 5 years for asthma and atopy outcomes.

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...

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.

78 FR 3897 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2013-01-17

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... number of work days aggregating at least 250 work days, occurring either solely under this employment or...

78 FR 3898 - Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Science.gov (United States)

2013-01-17

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort AGENCY: National Institute for Occupational Safety and Health... number of work days aggregating at least 250 work days, occurring either solely under this employment or...

Prospective cohort study of tea consumption and risk of digestive system cancers: results from the Shanghai Women's Health Study123

Science.gov (United States)

Nechuta, Sarah; Shu, Xiao-Ou; Li, Hong-Lan; Yang, Gong; Ji, Bu-Tian; Xiang, Yong-Bing; Cai, Hui; Chow, Wong-Ho; Gao, Yu-Tang

2012-01-01

Background: Data from in vitro and animal studies support a protective role for tea in the etiology of digestive system cancers; however, results from prospective cohort studies have been inconsistent. In addition, to our knowledge, no study has investigated the association of tea consumption with the incidence of all digestive system cancers in Chinese women. Objective: We investigated the association of regular tea intake (≥3 times/wk for >6 mo) with risk of digestive system cancers. Design: We used the Shanghai Women's Health Study, a population-based prospective cohort study of middle-aged and older Chinese women who were recruited in 1996–2000. Adjusted HRs and associated 95% CIs were derived from Cox regression models. Results: After a mean follow-up of 11 y, 1255 digestive system cancers occurred (stomach, esophagus, colorectal, liver, pancreas, and gallbladder/bile duct cancers) in 69,310 nonsmoking and non–alcohol-drinking women. In comparison with women who never drank tea, regular tea intake (mostly green tea) was associated with reduced risk of all digestive system cancers combined (HR: 0.86; 95% CI: 0.74, 0.98), and the reduction in risk increased as the amount and years of tea consumption increased (P-trend = 0.01 and P-trend tea/mo (∼2–3 cups/d) had a 21% reduced risk of digestive system cancers combined (HR: 0.79; 95% CI: 0.63, 0.99). The inverse association was found primarily for colorectal and stomach/esophageal cancers. Conclusion: In this large prospective cohort study, tea consumption was associated with reduced risk of colorectal and stomach/esophageal cancers in Chinese women. PMID:23053557

Perceived age as clinically useful biomarker of ageing: cohort study

DEFF Research Database (Denmark)

Christensen, Kaare; Thinggaard, Mikael; McGue, Matt

2009-01-01

OBJECTIVE: To determine whether perceived age correlates with survival and important age related phenotypes. DESIGN: Follow-up study, with survival of twins determined up to January 2008, by which time 675 (37%) had died. SETTING: Population based twin cohort in Denmark. PARTICIPANTS: 20 nurses, 10...... young men, and 11 older women (assessors); 1826 twins aged >or=70. MAIN OUTCOME MEASURES: Assessors: perceived age of twins from photographs. Twins: physical and cognitive tests and molecular biomarker of ageing (leucocyte telomere length). RESULTS: For all three groups of assessors, perceived age...... increased with increasing discordance in perceived age within the twin pair-that is, the bigger the difference in perceived age within the pair, the more likely that the older looking twin died first. Twin analyses suggested that common genetic factors influence both perceived age and survival. Perceived...

Severe adverse maternal outcomes among low risk women with planned home versus hospital births in the Netherlands: nationwide cohort study

NARCIS (Netherlands)

de Jonge, J.; Mesman, J.A.J.M.; Manniën, J.; Zwart, J.J.; van Dillen, J.; van Roosmalen, J.

2013-01-01

Objectives: To test the hypothesis that low risk women at the onset of labour with planned home birth have a higher rate of severe acute maternal morbidity than women with planned hospital birth, and to compare the rate of postpartum haemorrhage and manual removal of placenta. Design: Cohort study

Selective reporting bias of harm outcomes within studies: findings from a cohort of systematic reviews.

Science.gov (United States)

Saini, Pooja; Loke, Yoon K; Gamble, Carrol; Altman, Douglas G; Williamson, Paula R; Kirkham, Jamie J

2014-11-21

To determine the extent and nature of selective non-reporting of harm outcomes in clinical studies that were eligible for inclusion in a cohort of systematic reviews. Cohort study of systematic reviews from two databases. Outcome reporting bias in trials for harm outcomes (ORBIT II) in systematic reviews from the Cochrane Library and a separate cohort of systematic reviews of adverse events. 92 systematic reviews of randomised controlled trials and non-randomised studies published in the Cochrane Library between issue 9, 2012 and issue 2, 2013 (Cochrane cohort) and 230 systematic reviews published between 1 January 2007 and 31 December 2011 in other publications, synthesising data on harm outcomes (adverse event cohort). A 13 point classification system for missing outcome data on harm was developed and applied to the studies. 86% (79/92) of reviews in the Cochrane cohort did not include full data from the main harm outcome of interest of each review for all of the eligible studies included within that review; 76% (173/230) for the adverse event cohort. Overall, the single primary harm outcome was inadequately reported in 76% (705/931) of the studies included in the 92 reviews from the Cochrane cohort and not reported in 47% (4159/8837) of the 230 reviews in the adverse event cohort. In a sample of primary studies not reporting on the single primary harm outcome in the review, scrutiny of the study publication revealed that outcome reporting bias was suspected in nearly two thirds (63%, 248/393). The number of reviews suspected of outcome reporting bias as a result of missing or partially reported harm related outcomes from at least one eligible study is high. The declaration of important harms and the quality of the reporting of harm outcomes must be improved in both primary studies and systematic reviews. © Saini et al 2014.

The Tennessee Children's Respiratory Initiative: Objectives, design and recruitment results of a prospective cohort study investigating infant viral respiratory illness and the development of asthma and allergic diseases.

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Hartert, Tina V; Carroll, Kecia; Gebretsadik, Tebeb; Woodward, Kimberly; Minton, Patricia

2010-05-01

The 'attack rate' of asthma following viral lower respiratory tract infections (LRTI) is about 3-4 fold higher than that of the general population; however, the majority of children who develop viral LRTI during infancy do not develop asthma, and asthma incidence has been observed to continuously decrease with age. Thus, we do not understand how viral LRTI either predispose or serve as a marker of children to develop asthma. The Tennessee Children's Respiratory Initiative has been established as a longitudinal prospective investigation of infants and their biological mothers. The primary goals are to investigate both the acute and the long-term health consequences of varying severity and aetiology of clinically significant viral respiratory tract infections on early childhood outcomes. Over four respiratory viral seasons, 2004–2008, term, predominantly non-low weight previously healthy infants and their biological mothers were enrolled during an infant's acute viral respiratory illness.Longitudinal follow up to age 6 years is ongoing [corrected]. This report describes the study objectives, design and recruitment results of the over 650 families enrolled in this longitudinal investigation. The Tennessee Children's Respiratory Initiative is additionally unique because it is designed in parallel with a large retrospective birth cohort of over 95,000 mother-infant dyads with similar objectives to investigate the role of respiratory viral infection severity and aetiology in the development of asthma. Future reports from this cohort will help to clarify the complex relationship between infant respiratory viral infection severity, aetiology, atopic predisposition and the subsequent development of early childhood asthma and atopic diseases.

Prognostic factors of whiplash-associated disorders: a systematic review of prospective cohort studies.

Science.gov (United States)

Scholten-Peeters, Gwendolijne G M; Verhagen, Arianne P; Bekkering, Geertruida E; van der Windt, Daniëlle A W M; Barnsley, Les; Oostendorp, Rob A B; Hendriks, Erik J M

2003-07-01

We present a systematic review of prospective cohort studies. Our aim was to assess prognostic factors associated with functional recovery of patients with whiplash injuries. The failure of some patients to recover following whiplash injury has been linked to a number of prognostic factors. However, there is some inconsistency in the literature and there have been no systematic attempts to analyze the level of evidence for prognostic factors in whiplash recovery. Studies were selected for inclusion following a comprehensive search of MEDLINE, EMBASE, CINAHL, the database of the Dutch Institute of Allied Health Professions up until April 2002 and hand searches of the reference lists of retrieved articles. Studies were selected if the objective was to assess prognostic factors associated with recovery; the design was a prospective cohort study; the study population included at least an identifiable subgroup of patients suffering from a whiplash injury; and the paper was a full report published in English, German, French or Dutch. The methodological quality was independently assessed by two reviewers. A study was considered to be of 'high quality' if it satisfied at least 50% of the maximum available quality score. Two independent reviewers extracted data and the association between prognostic factors and functional recovery was calculated in terms of risk estimates. Fifty papers reporting on twenty-nine cohorts were included in the review. Twelve cohorts were considered to be of 'high quality'. Because of the heterogeneity of patient selection, type of prognostic factors and outcome measures, no statistical pooling was able to be performed. Strong evidence was found for high initial pain intensity being an adverse prognostic factor. There was strong evidence that for older age, female gender, high acute psychological response, angular deformity of the neck, rear-end collision, and compensation not being associated with an adverse prognosis. Several physical (e

Nerve conduction in relation to vibration exposure - a non-positive cohort study

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Nilsson Tohr

2010-07-01

Full Text Available Abstract Background Peripheral neuropathy is one of the principal clinical disorders in workers with hand-arm vibration syndrome. Electrophysiological studies aimed at defining the nature of the injury have provided conflicting results. One reason for this lack of consistency might be the sparsity of published longitudinal etiological studies with both good assessment of exposure and a well-defined measure of disease. Against this background we measured conduction velocities in the hand after having assessed vibration exposure over 21 years in a cohort of manual workers. Methods The study group consisted of 155 male office and manual workers at an engineering plant that manufactured pulp and paper machinery. The study has a longitudinal design regarding exposure assessment and a cross-sectional design regarding the outcome of nerve conduction. Hand-arm vibration dose was calculated as the product of self-reported occupational exposure, collected by questionnaire and interviews, and the measured or estimated hand-arm vibration exposure in 1987, 1992, 1997, 2002, and 2008. Distal motor latencies in median and ulnar nerves and sensory nerve conduction over the carpal tunnel and the finger-palm segments in the median nerve were measured in 2008. Before the nerve conduction measurement, the subjects were systemically warmed by a bicycle ergometer test. Results There were no differences in distal latencies between subjects exposed to hand-arm vibration and unexposed subjects, neither in the sensory conduction latencies of the median nerve, nor in the motor conduction latencies of the median and ulnar nerves. Seven subjects (9% in the exposed group and three subjects (12% in the unexposed group had both pathological sensory nerve conduction at the wrist and symptoms suggestive of carpal tunnel syndrome. Conclusion Nerve conduction measurements of peripheral hand nerves revealed no exposure-response association between hand-arm vibration exposure and

Polysomnographic Findings and Clinical Correlates in Huntington Disease: A Cross-Sectional Cohort Study

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Piano, Carla; Losurdo, Anna; Della Marca, Giacomo; Solito, Marcella; Calandra-Buonaura, Giovanna; Provini, Federica; Bentivoglio, Anna Rita; Cortelli, Pietro

2015-01-01

Study Objectives: To evaluate the sleep pattern and the motor activity during sleep in a cohort of patients affected by Huntington disease (HD). Design: Cross-sectional cohort study. Setting: Sleep laboratory. Patients: Thirty HD patients, 16 women and 14 men (mean age 57.3 ± 12.2 y); 30 matched healthy controls (mean age 56.5 ± 11.8 y). Interventions: Subjective sleep evaluation: Epworth Sleepiness Scale (ESS); Berlin's Questionnaire, interview for restless legs syndrome (RLS), questionnaire for REM sleep behavior disorder (RBD). Clinical evaluation: disease duration, clinical severity (unified Huntington disease motor rating scale [UHDMRS]), genetic tests. Laboratory-based full-night attended video-polysomnography (V-PSG). Measurements and Results: The duration of the disease was 9.4 ± 4.4 y, UHMDRS score was 55.5 ± 23.4, CAG repeats were 44.3 ± 4.1. Body mass index was 21.9 ± 4.0 kg/m2. No patients or caregivers reported poor sleep quality. Two patients reported symptoms of RLS. Eight patients had an ESS score ≥ 9. Eight patients had high risk of obstructive sleep apnea. At the RBD questionnaire, two patients had a pathological score. HD patients, compared to controls, showed shorter sleep, reduced sleep efficiency index, and increased arousals and awakenings. Four patients presented with sleep disordered breathing (SDB). Periodic limb movements (PLMs) during wake and sleep were observed in all patients. No episode of RBD was observed in the V-PSG recordings, and no patients showed rapid eye movement (REM) sleep without atonia. The disease duration correlated with ESS score (P Marca G, Solito M, Calandra-Buonaura G, Provini F, Bentivoglio AR, Cortelli P. Polysomnographic findings and clinical correlates in Huntington disease: a cross-sectional cohort study. SLEEP 2015;38(9):1489–1495. PMID:25845698

Professional football players at risk for non-acute groin injuries during the first half of the season: A prospective cohort study in The Netherlands

NARCIS (Netherlands)

Gouttebarge, Vincent; Veenstra, Ersot; Goedegebuure, Simon; Frings-Dresen, Monique; Kuijer, Paul

2018-01-01

OBJECTIVES: To study the incidence, diagnostics, treatment, anatomical region and return to play of non-acute groin injuries among professional footballers in the Netherlands. DESIGN: Prospective cohort study. METHODS: Medical staff members of all Dutch professional football clubs, recording

The BioFIND study: Characteristics of a clinically typical Parkinson's disease biomarker cohort

Science.gov (United States)

Goldman, Jennifer G.; Alcalay, Roy N.; Xie, Tao; Tuite, Paul; Henchcliffe, Claire; Hogarth, Penelope; Amara, Amy W.; Frank, Samuel; Rudolph, Alice; Casaceli, Cynthia; Andrews, Howard; Gwinn, Katrina; Sutherland, Margaret; Kopil, Catherine; Vincent, Lona; Frasier, Mark

2016-01-01

ABSTRACT Background Identifying PD‐specific biomarkers in biofluids will greatly aid in diagnosis, monitoring progression, and therapeutic interventions. PD biomarkers have been limited by poor discriminatory power, partly driven by heterogeneity of the disease, variability of collection protocols, and focus on de novo, unmedicated patients. Thus, a platform for biomarker discovery and validation in well‐characterized, clinically typical, moderate to advanced PD cohorts is critically needed. Methods BioFIND (Fox Investigation for New Discovery of Biomarkers in Parkinson's Disease) is a cross‐sectional, multicenter biomarker study that established a repository of clinical data, blood, DNA, RNA, CSF, saliva, and urine samples from 118 moderate to advanced PD and 88 healthy control subjects. Inclusion criteria were designed to maximize diagnostic specificity by selecting participants with clinically typical PD symptoms, and clinical data and biospecimen collection utilized standardized procedures to minimize variability across sites. Results We present the study methodology and data on the cohort's clinical characteristics. Motor scores and biospecimen samples including plasma are available for practically defined off and on states and thus enable testing the effects of PD medications on biomarkers. Other biospecimens are available from off state PD assessments and from controls. Conclusion Our cohort provides a valuable resource for biomarker discovery and validation in PD. Clinical data and biospecimens, available through The Michael J. Fox Foundation for Parkinson's Research and the National Institute of Neurological Disorders and Stroke, can serve as a platform for discovering biomarkers in clinically typical PD and comparisons across PD's broad and heterogeneous spectrum. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society PMID:27113479

Predictive accuracy of Edinburgh Postnatal Depression Scale assessment during pregnancy for the risk of developing postpartum depressive symptoms : a prospective cohort study

NARCIS (Netherlands)

Meijer, J. L.; Beijers, C.; van Pampus, M. G.; Verbeek, T.; Stolk, R. P.; Milgrom, J.; Bockting, C. L. H.; Burger, H.

2014-01-01

ObjectiveTo investigate whether the 10-item Edinburgh Postnatal Depression Scale (EPDS) administered antenatally is accurate in predicting postpartum depressive symptoms, and whether a two-item EPDS has similar predictive accuracy. DesignProspective cohort study. SettingObstetric care in the

Birth weight ratio as an alternative to birth weight percentile to express infant weight in research and clinical practice: a nationwide cohort study

NARCIS (Netherlands)

Voskamp, Bart Jan; Kazemier, Brenda M.; Schuit, Ewoud; Mol, Ben Willem J.; Buimer, Maarten; Pajkrt, Eva; Ganzevoort, Wessel

2014-01-01

Objective. To compare birth weight ratio and birth weight percentile to express infant weight when assessing pregnancy outcome. Study Design. We performed a national cohort study. Birth weight ratio was calculated as the observed birth weight divided by the median birth weight for gestational age.

Family Structure and Childhood Obesity, Early Childhood Longitudinal Study ? Kindergarten Cohort

OpenAIRE

Chen, Alex Y.; Escarce, Jos? J.

2010-01-01

Introduction Little is known about the effect of family structure on childhood obesity among US children. This study examines the effect of number of parents and number of siblings on children's body mass index and risk of obesity. Methods We conducted a secondary data analysis of the Early Childhood Longitudinal Study ? Kindergarten Cohort (ECLS-K), which consists of a nationally representative cohort of children who entered kindergarten during 1998-1999. Our analyses included 2 cross-sectio...

Hypospadias in a cohort of 1072 Danish newborn boys

DEFF Research Database (Denmark)

Boisen, K A; Chellakooty, M; Schmidt, I M

2005-01-01

and reproductive hormone levels at 3 months of age. DESIGN: A prospective cohort study was conducted with 3-yr follow-up (1997-2004). SETTING: The population-based study was conducted at the University Hospital of Copenhagen. PARTICIPANTS: A total of 1072 Danish boys were consecutively recruited antenatally...... = 0.023) were significantly lower, and FSH was significantly higher (1.48 vs. 1.15 IU/liter; P = 0.007) in boys with hypospadias, compared with healthy boys. CONCLUSIONS: We found a surprisingly high total rate of hypospadias of 4.6% in this large prospective cohort study. Seventy-two percent...

Born in Bradford’s Better Start: an experimental birth cohort study to evaluate the impact of early life interventions

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Josie Dickerson

2016-08-01

Full Text Available Abstract Background Early interventions are recognised as key to improving life chances for children and reducing inequalities in health and well-being, however there is a paucity of high quality research into the effectiveness of interventions to address childhood health and development outcomes. Planning and implementing standalone RCTs for multiple, individual interventions would be slow, cumbersome and expensive. This paper describes the protocol for an innovative experimental birth cohort: Born in Bradford’s Better Start (BiBBS that will simultaneously evaluate the impact of multiple early life interventions using efficient study designs. Better Start Bradford (BSB has been allocated £49 million from the Big Lottery Fund to implement 22 interventions to improve outcomes for children aged 0–3 in three key areas: social and emotional development; communication and language development; and nutrition and obesity. The interventions will be implemented in three deprived and ethnically diverse inner city areas of Bradford. Method The BiBBS study aims to recruit 5000 babies, their mothers and their mothers’ partners over 5 years from January 2016-December 2020. Demographic and socioeconomic information, physical and mental health, lifestyle factors and biological samples will be collected during pregnancy. Parents and children will be linked to their routine health and local authority (including education data throughout the children’s lives. Their participation in BSB interventions will also be tracked. BiBBS will test interventions using the Trials within Cohorts (TwiCs approach and other quasi-experimental designs where TwiCs are neither feasible nor ethical, to evaluate these early life interventions. The effects of single interventions, and the cumulative effects of stacked (multiple interventions on health and social outcomes during the critical early years will be measured. Discussion The focus of the BiBBS cohort is on

Toenail selenium status and the risk of Barrett's esophagus: The Netherlands Cohort Study

NARCIS (Netherlands)

Steevens, J.; Schouten, L.J.; Driessen, A.L.C.; Huysentruyt, C.J.R.; Keulemans, Y.C.A.; Goldbohm, R.A.; Brandt, P.A. van den

2010-01-01

Objective: To investigate the association between selenium and the risk of Barrett's esophagus (BE), the precursor lesion of esophageal adenocarcinoma. Methods: Data from the prospective Netherlands Cohort Study were used. This cohort study was initiated in 1986, when 120,852 subjects aged 55-69

VTE Risk assessment - a prognostic Model: BATER Cohort Study of young women.

Science.gov (United States)

Heinemann, Lothar Aj; Dominh, Thai; Assmann, Anita; Schramm, Wolfgang; Schürmann, Rolf; Hilpert, Jan; Spannagl, Michael

2005-04-18

BACKGROUND: Community-based cohort studies are not available that evaluated the predictive power of both clinical and genetic risk factors for venous thromboembolism (VTE). There is, however, clinical need to forecast the likelihood of future occurrence of VTE, at least qualitatively, to support decisions about intensity of diagnostic or preventive measures. MATERIALS AND METHODS: A 10-year observation period of the Bavarian Thromboembolic Risk (BATER) study, a cohort study of 4337 women (18-55 years), was used to develop a predictive model of VTE based on clinical and genetic variables at baseline (1993). The objective was to prepare a probabilistic scheme that discriminates women with virtually no VTE risk from those at higher levels of absolute VTE risk in the foreseeable future. A multivariate analysis determined which variables at baseline were the best predictors of a future VTE event, provided a ranking according to the predictive power, and permitted to design a simple graphic scheme to assess the individual VTE risk using five predictor variables. RESULTS: Thirty-four new confirmed VTEs occurred during the observation period of over 32,000 women-years (WYs). A model was developed mainly based on clinical information (personal history of previous VTE and family history of VTE, age, BMI) and one composite genetic risk markers (combining Factor V Leiden and Prothrombin G20210A Mutation). Four levels of increasing VTE risk were arbitrarily defined to map the prevalence in the study population: No/low risk of VTE (61.3%), moderate risk (21.1%), high risk (6.0%), very high risk of future VTE (0.9%). In 10.6% of the population the risk assessment was not possible due to lacking VTE cases. The average incidence rates for VTE in these four levels were: 4.1, 12.3, 47.2, and 170.5 per 104 WYs for no, moderate, high, and very high risk, respectively. CONCLUSION: Our prognostic tool - containing clinical information (and if available also genetic data) - seems to be

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

Premature death of adult adoptees: analyses of a case-cohort sample.

Science.gov (United States)

Petersen, Liselotte; Andersen, Per Kragh; Sørensen, Thorkild I A

2005-05-01

Genetic and environmental influence on risk of premature death in adulthood was investigated by estimating the associations in total and cause-specific mortality of adult Danish adoptees and their biological and adoptive parents. Among all 14,425 non-familial adoptions formally granted in Denmark during the period 1924 through 1947, we selected the study population according to a case-cohort sampling design. As the case-control design, the case-cohort design has the advantage of economic data collection and little loss in statistical efficiency, but the case-cohort sample has the additional advantages that rate ratio estimates may be obtained, and re-use of the cohort sample in future studies of other outcomes is possible. Analyses were performed using Kalbfleisch and Lawless's estimator for hazard ratio, and robust estimation for variances. In the main analyses the sample was restricted to birth years of the adoptees 1924 and after, and age of transfer to the adoptive parents before 7 years, and age at death was restricted to 16 to 70 years. The results showed a higher mortality among adoptees, whose biological parents died in the age range of 16 to 70 years; this was significant for deaths from natural causes, vascular causes and all causes. No influence was seen from early death of adoptive parents, regardless of cause of death. (c) 2005 Wiley-Liss, Inc.

Cohort Profile: Antiretroviral Therapy Cohort Collaboration (ART-CC)

Science.gov (United States)

May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D’Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan AC

2014-01-01

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70 000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). PMID:23599235

Non-cancer morbidity among Estonian Chernobyl cleanup workers: a register-based cohort study.

Science.gov (United States)

Rahu, Kaja; Bromet, Evelyn J; Hakulinen, Timo; Auvinen, Anssi; Uusküla, Anneli; Rahu, Mati

2014-05-14

To examine non-cancer morbidity in the Estonian Chernobyl cleanup workers cohort compared with the population sample with special attention to radiation-related diseases and mental health disorders. Register-based cohort study. Estonia. An exposed cohort of 3680 men (cleanup workers) and an unexposed cohort of 7631 men (population sample) were followed from 2004 to 2012 through the Population Registry and Health Insurance Fund database. Morbidity in the exposed cohort compared with the unexposed controls was estimated in terms of rate ratio (RR) with 95% CIs using Poisson regression models. Elevated morbidity in the exposed cohort was found for diseases of the nervous system, digestive system, musculoskeletal system, ischaemic heart disease and for external causes. The most salient excess risk was observed for thyroid diseases (RR=1.69; 95% CI 1.38 to 2.07), intentional self-harm (RR=1.47; 95% CI 1.04 to 2.09) and selected alcohol-related diagnoses (RR=1.25; 95% CI 1.12 to 1.39). No increase in morbidity for stress reactions, depression, headaches or sleep disorders was detected. No obvious excess morbidity consistent with biological effects of radiation was seen in the exposed cohort, with the possible exception of benign thyroid diseases. Increased alcohol-induced morbidity may reflect alcohol abuse, and could underlie some of the higher morbidity rates. Mental disorders in the exposed cohort were probably under-reported. The future challenge will be to study mental and physical comorbidities in the Chernobyl cleanup workers cohort. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Foot pronation is not associated with increased injury risk in novice runners wearing a neutral shoe : a 1-year prospective cohort study

NARCIS (Netherlands)

Nielsen, Rasmus Oestergaard; Buist, Ida; Parner, Erik Thorlund; Nohr, Ellen Aagaard; Sorensen, Henrik; Lind, Martin; Rasmussen, Sten

Objective To investigate if running distance to first running-related injury varies between foot postures in novice runners wearing neutral shoes. Design A 1-year epidemiological observational prospective cohort study. Setting Denmark. Participants A total of 927 novice runners equivalent to 1854

Cancer in ANCA-Associated Glomerulonephritis: A Registry-Based Cohort Study

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Sanjeevan Sriskandarajah

2017-01-01

Full Text Available Background. Immunosuppressive therapy for antineutrophil cytoplasmic antibody-associated vasculitis has been associated with increased malignancy risk. Objectives. To quantify the cancer risk associated with contemporary cyclophosphamide-sparing protocols. Methods. Patients from the Norwegian Kidney Biopsy Registry between 1988 and 2012 who had biopsy-verified pauci-immune glomerulonephritis and positive antineutrophil cytoplasmic antibody (ANCA serology were included. Standardised incidence ratios (SIRs were calculated to compare the study cohort with the general population. Results. The study cohort included 419 patients. During 3010 person-years, cancer developed in 41 patients (9.79%; the expected number of cancer cases was 37.5 (8.95%. The cohort had SIRs as follows: 1.09, all cancer types (95% CI, 0.81 to 1.49; 0.96, all types except nonmelanoma skin cancer (95% CI, 0.69 to 1.34; 3.40, nonmelanoma skin cancer (95% CI, 1.62 to 7.14; 3.52, hematologic cancer (95% CI, 1.32 to 9.37; 2.12, posttransplant cancer (95% CI, 1.01 to 4.44; and 1.53, during the 1–5-year follow-up after diagnosis (95% CI, 1.01 to 2.32. Conclusions. Cancer risk did not increase significantly in this cohort with ANCA-associated glomerulonephritis. However, increased risk of nonmelanoma skin cancer, posttransplant cancer, and hematologic cancer indicates an association between immunosuppression and malignancy.

The Korea Nurses' Health Study: A Prospective Cohort Study.

Science.gov (United States)

Kim, Oksoo; Ahn, Younjhin; Lee, Hea-Young; Jang, Hee Jung; Kim, Sue; Lee, Jung Eun; Jung, Heeja; Cho, Eunyoung; Lim, Joong-Yeon; Kim, Min-Ju; Willett, Walter C; Chavarro, Jorge E; Park, Hyun-Young

2017-08-01

The Korea Nurses' Health Study (KNHS) is a prospective cohort study of female nurses, focusing on the effects of occupational, environmental, and lifestyle risk factors on the health of Korean women. Female registered nurses aged 20-45 years and living in the Republic of Korea were invited to join the study, which began in July 2013. They were asked to complete a web-based baseline survey. The study protocols and questionnaires related to the KNHS are based on the Nurses' Health Study 3 (NHS3) in the United States, although they were modified to reflect the Korean lifestyle. Participants were asked about demographic, lifestyle factors, disease history, occupational exposure, reproductive factors, and dietary habits during their adolescence: Follow-up questionnaires were/will be completed at 6-8 month intervals after the baseline survey. If a participant became pregnant, she answered additional questionnaires containing pregnancy-related information. Among 157,569 eligible female nurses, 20,613 (13.1%) completed the web-based baseline questionnaire. The mean age of the participants was 29.4 ± 5.9 years, and more than half of them were in their 20s. Eighty-eight percent of the participants had worked night shifts as a nurse (mean, 5.3 ± 4.3 nights per month). Approximately 80% of the participants had a body mass index below 23 kg/m 2 . Gastrointestinal diseases were the most prevalent health issues (25.9%). The findings from this prospective cohort study will help to identify the effects of lifestyle-related and occupational factors on reproductive health and development of chronic diseases in Korean women.

The Lothian Birth Cohort 1936: a study to examine influences on cognitive ageing from age 11 to age 70 and beyond

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Whalley Lawrence J

2007-12-01

Full Text Available Abstract Background Cognitive ageing is a major burden for society and a major influence in lowering people's independence and quality of life. It is the most feared aspect of ageing. There are large individual differences in age-related cognitive changes. Seeking the determinants of cognitive ageing is a research priority. A limitation of many studies is the lack of a sufficiently long period between cognitive assessments to examine determinants. Here, the aim is to examine influences on cognitive ageing between childhood and old age. Methods/Design The study is designed as a follow-up cohort study. The participants comprise surviving members of the Scottish Mental Survey of 1947 (SMS1947; N = 70,805 who reside in the Edinburgh area (Lothian of Scotland. The SMS1947 applied a valid test of general intelligence to all children born in 1936 and attending Scottish schools in June 1947. A total of 1091 participants make up the Lothian Birth Cohort 1936. They undertook: a medical interview and examination; physical fitness testing; extensive cognitive testing (reasoning, memory, speed of information processing, and executive function; personality, quality of life and other psycho-social questionnaires; and a food frequency questionnaire. They have taken the same mental ability test (the Moray House Test No. 12 at age 11 and age 70. They provided blood samples for DNA extraction and testing and other biomarker analyses. Here we describe the background and aims of the study, the recruitment procedures and details of numbers tested, and the details of all examinations. Discussion The principal strength of this cohort is the rarely captured phenotype of lifetime cognitive change. There is additional rich information to examine the determinants of individual differences in this lifetime cognitive change. This protocol report is important in alerting other researchers to the data available in the cohort.

Risk of lymphoma and leukaemia after bacille Calmette-Guérin and smallpox vaccination: a Danish case-cohort study

DEFF Research Database (Denmark)

Villumsen, Marie; Sørup, Signe; Jess, Tine

2009-01-01

Vaccines may have non-specific effects as suggested mainly in mortality studies from low-income countries. The objective was to examine the effects of BCG and smallpox vaccinations on subsequent risk of lymphoma and leukaemia in a Danish population experiencing rapid out-phasing of these vaccines...... cohort and analysed in a case-cohort design. BCG vaccination reduced the risk of lymphomas (HR=0.49 (95% CI: 0.26-0.93)), whereas smallpox vaccination did not (HR=1.32 (0.56-3.08)). With the small number of leukaemia cases, the analysis of leukaemia had limited power (BCG vaccination HR=0.81 (0.......31-2.16); smallpox vaccination HR=1.32 (0.49-3.53)). The present study with very reliable vaccine history information indicates a beneficial effect of BCG vaccination on the risk of lymphomas....

Etiology and prognosis of pregnancy-related pelvic girdle pain; design of a longitudinal study

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Kroese Mariëlle EAL

2005-01-01

Full Text Available Abstract Background Absence of knowledge of pregnancy-related pelvic girdle pain (PPGP has prompted the start of a large cohort study in the Netherlands. The objective of this study was to investigate the prevalence and incidence of PPGP, to identify risk factors involved in the onset and to determine the prognosis of pregnancy-related pelvic girdle pain. Methods/design 7,526 pregnant women of the southeast of the Netherlands participated in a prospective cohort study. During a 2-year period, they were recruited by midwives and gynecologists at 14 weeks of pregnancy. Participants completed a questionnaire at baseline, at 30 weeks of pregnancy, at 2 weeks after delivery, at 6 months after delivery and at 1 year after delivery. The study uses extensive questionnaires with questions ranging from physical complaints, limitations in activities, restriction in participation, work situation, demographics, lifestyle, pregnancy-related factors and psychosocial factors. Discussion This large-scale prospective cohort study will provide reliable insights in incidence, prevalence and factors related to etiology and prognosis of pregnancy-related pelvic girdle pain.

The German MultiCare-study: Patterns of multimorbidity in primary health care – protocol of a prospective cohort study

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Schäfer Ingmar

2009-08-01

Full Text Available Abstract Background Multimorbidity is a highly frequent condition in older people, but well designed longitudinal studies on the impact of multimorbidity on patients and the health care system have been remarkably scarce in numbers until today. Little is known about the long term impact of multimorbidity on the patients' life expectancy, functional status and quality of life as well as health care utilization over time. As a consequence, there is little help for GPs in adjusting care for these patients, even though studies suggest that adhering to present clinical practice guidelines in the care of patients with multimorbidity may have adverse effects. Methods/Design The study is designed as a multicentre prospective, observational cohort study of 3.050 patients aged 65 to 85 at baseline with at least three different diagnoses out of a list of 29 illnesses and syndromes. The patients will be recruited in approx. 120 to 150 GP surgeries in 8 study centres distributed across Germany. Information about the patients' morbidity will be collected mainly in GP interviews and from chart reviews. Functional status, resources/risk factors, health care utilization and additional morbidity data will be assessed in patient interviews, in which a multitude of well established standardized questionnaires and tests will be performed. Discussion The main aim of the cohort study is to monitor the course of the illness process and to analyse for which reasons medical conditions are stable, deteriorating or only temporarily present. First, clusters of combinations of diseases/disorders (multimorbidity patterns with a comparable impact (e.g. on quality of life and/or functional status will be identified. Then the development of these clusters over time will be analysed, especially with regard to prognostic variables and the somatic, psychological and social consequences as well as the utilization of health care resources. The results will allow the development of an

Primary Sjogren's syndrome and the risk of acute pancreatitis: a nationwide cohort study.

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Chang, Chi-Ching; Chang, Yu-Sheng; Wang, Shu-Hung; Lin, Shyr-Yi; Chen, Yi-Hsuan; Chen, Jin Hua

2017-08-11

Studies on the risk of acute pancreatitis in patients with primary Sjogren's syndrome (pSS) are limited. We evaluated the effects of pSS on the risk of acute pancreatitis in a nationwide, population-based cohort in Taiwan. Population-based retrospective cohort study. We studied the claims data of the >97% Taiwan population from 2002 to 2012. We identified 9468 patients with pSS by using the catastrophic illness registry of the National Health Insurance Database in Taiwan. We also selected 37 872 controls that were randomly frequency matched by age (in 5 year bands), sex and index year from the general population. We analysed the risk of acute pancreatitis by using Cox proportional hazards regression models including sex, age and comorbidities. From 23.74 million people in the cohort, 9468 patients with pSS (87% women, mean age=55.6 years) and 37 872 controls were followed-up for 4.64 and 4.74 years, respectively. A total of 44 cases of acute pancreatitis were identified in the pSS cohort versus 105 cases in the non-pSS cohort. Multivariate Cox regression analysis indicated that the incidence rate of acute pancreatitis was significantly higher in the pSS cohort than in the non-pSS cohort (adjusted HR (aHR) 1.48, 95% CI 1.03 to 2.12). Cyclophosphamide use increased the risk of acute pancreatitis (aHR 5.27, 95% CI 1.16 to 23.86). By contrast, hydroxychloroquine reduced the risk of acute pancreatitis (aHR 0.23, 95% CI 0.09 to 0.55). This nationwide, retrospective cohort study demonstrated that the risk of acute pancreatitis was significantly higher in patients with pSS than in the general population. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The effects of exercise and weight loss in overweight patients with hip osteoarthritis: design of a prospective cohort study

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van der Meer Klaas

2009-02-01

Full Text Available Abstract Background Hip osteoarthritis (OA is recognised as a substantial source of disability, with pain and loss of function as principal symptoms. An aging society and a growing number of overweight people, which is considered a risk factor for OA, contribute to the growing number of cases of hip OA. In knee OA patients, exercise as a single treatment is proven to be very effective towards counteracting pain and physical functionality, but the combination of weight loss and exercise is demonstrated to be even more effective. Exercise as a treatment for hip OA patients is also effective, however evidence is lacking for the combination of weight loss and exercise. Consequently, the aim of this study is to get a first impression of the potential effectiveness of exercise and weight loss in overweight patients suffering from hip OA. Methods/Design This is a prospective cohort study. Patients aged 25 or older, overweight (BMI > 25 or obese (BMI > 30, with clinical and radiographic evidence of OA of the hip and able to attend exercise sessions will be included. The intervention is an 8-month exercise and weight-loss lifestyle program. Main goal is to increase aerobic capacity, lose weight and stimulate a low-calorie and active lifestyle. Primary outcome is self-reported physical functioning. Secondary outcomes include pain, stiffness, health-related quality of life and habitual activity level. Weight loss in kilograms and percentage of fat-free mass will also be measured. Discussion The results of this study will give a first impression of potential effectiveness of exercise and weight loss as a combination program for patients with OA of the hip. Once this program is proven to be effective it may lead to postponing the moment of total hip replacement. Trial Registration number NTR1053

Incidence, severity, aetiology and type of neck injury in men's amateur rugby union: a prospective cohort study

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Pollard Henry P

2010-07-01

Full Text Available Abstract Background There is a paucity of epidemiological data on neck injury in amateur rugby union populations. The objective of this study was to determine the incidence, severity, aetiology and type of neck injury in Australian men's amateur rugby union. Methods Data was collected from a cohort of 262 participants from two Australian amateur men's rugby union clubs via a prospective cohort study design. A modified version of the Rugby Union Injury Report Form for Games and Training was used by the clubs physiotherapist or chiropractor in data collection. Results The participants sustained 90 (eight recurrent neck injuries. Exposure time was calculated at 31143.8 hours of play (12863.8 hours of match time and 18280 hours of training. Incidence of neck injury was 2.9 injuries/1000 player-hours (95%CI: 2.3, 3.6. As a consequence 69.3% neck injuries were minor, 17% mild, 6.8% moderate and 6.8% severe. Neck compression was the most frequent aetiology and was weakly associated with severity. Cervical facet injury was the most frequent neck injury type. Conclusions This is the first prospective cohort study in an amateur men's rugby union population since the inception of professionalism that presents injury rate, severity, aetiology and injury type data for neck injury. Current epidemiological data should be sought when evaluating the risks associated with rugby union football.

Computerized test versus personal interview as admission methods for graduate nursing studies: A retrospective cohort study.

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Hazut, Koren; Romem, Pnina; Malkin, Smadar; Livshiz-Riven, Ilana

2016-12-01

The purpose of this study was to compare the predictive validity, economic efficiency, and faculty staff satisfaction of a computerized test versus a personal interview as admission methods for graduate nursing studies. A mixed method study was designed, including cross-sectional and retrospective cohorts, interviews, and cost analysis. One hundred and thirty-four students in the Master of Nursing program participated. The success of students in required core courses was similar in both admission method groups. The personal interview method was found to be a significant predictor of success, with cognitive variables the only significant contributors to the model. Higher satisfaction levels were reported with the computerized test compared with the personal interview method. The cost of the personal interview method, in annual hourly work, was 2.28 times higher than the computerized test. These findings may promote discussion regarding the cost benefit of the personal interview as an admission method for advanced academic studies in healthcare professions. © 2016 John Wiley & Sons Australia, Ltd.

The Alberta moving beyond breast cancer (AMBER cohort study: a prospective study of physical activity and health-related fitness in breast cancer survivors

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Courneya Kerry S

2012-11-01

Full Text Available Abstract Background Limited research has examined the association between physical activity, health-related fitness, and disease outcomes in breast cancer survivors. Here, we present the rationale and design of the Alberta Moving Beyond Breast Cancer (AMBER Study, a prospective cohort study designed specifically to examine the role of physical activity and health-related fitness in breast cancer survivorship from the time of diagnosis and for the balance of life. The AMBER Study will examine the role of physical activity and health-related fitness in facilitating treatment completion, alleviating treatment side effects, hastening recovery after treatments, improving long term quality of life, and reducing the risks of disease recurrence, other chronic diseases, and premature death. Methods/Design The AMBER Study will enroll 1500 newly diagnosed, incident, stage I-IIIc breast cancer survivors in Alberta, Canada over a 5 year period. Assessments will be made at baseline (within 90 days of surgery, 1 year, and 3 years consisting of objective and self-reported measurements of physical activity, health-related fitness, blood collection, lymphedema, patient-reported outcomes, and determinants of physical activity. A final assessment at 5 years will measure patient-reported data only. The cohort members will be followed for an additional 5 years for disease outcomes. Discussion The AMBER cohort will answer key questions related to physical activity and health-related fitness in breast cancer survivors including: (1 the independent and interactive associations of physical activity and health-related fitness with disease outcomes (e.g., recurrence, breast cancer-specific mortality, overall survival, treatment completion rates, symptoms and side effects (e.g., pain, lymphedema, fatigue, neuropathy, quality of life, and psychosocial functioning (e.g., anxiety, depression, self-esteem, happiness, (2 the determinants of physical activity and

A Prospective Cohort Study in Patients with Type 2 Diabetes Mellitus for Validation of Biomarkers (PROVALID – Study Design and Baseline Characteristics

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Susanne Eder

2018-02-01

Full Text Available Background/Aims: The prevalence of diabetes mellitus type 2 and kidney disease in these patients varies widely between European countries. Methods: In addition to store bio-samples the “Prospective cohort study in patients with type 2 diabetes mellitus for validation of biomarkers” collects information on history, physical status, laboratory measurements and medication in 4000 patients with diabetes mellitus type 2, being taken care of at the primary level of healthcare in 5 European countries (Austria, Hungary, Netherlands, Poland and Scotland. Next to comparing the rate of loss of eGFR between the countries, a further objective of the PROVALID study is to determine the 5-year cumulative incidence of renal and cardiovascular outcomes. Results: The mean age of the population recruited is 62.9±10 years, 54.6% are male and the mean BMI is 30.9±5.4 kg/m2. Metabolic control (median HBA1c 6.8 % (6.2; 7.5 is achieved via administration of metformin in 67.4% of the patients and insulin in 30.3%. Median systolic and diastolic blood pressure at recruitment is 135 (125; 146 and 80 (72; 85 mmHg, 65.4% of subjects received RAAS blocking agents. Mean eGFR is 80.7±29.2 ml/min/1.73m2 and median baseline albumin/creatinine ratio 8.3 mg (IQR: 3.8 and 25.1. Conclusion: PROVALID will provide information on incidence and progression of renal and cardiovascular disease and therapy in patients with type 2 diabetes mellitus in different European countries. Thus, in contrast to many other cohort studies we will be able to associate national clinical practise pattern with outcome in this highly vulnerable patient population.

Anthropometry, physical activity, and endometrial cancer risk: Results from the Netherlands Cohort Study

NARCIS (Netherlands)

Schouten, L.J.; Goldbohm, R.A.; Brandt, P.A. van den

2004-01-01

Although obesity is an established risk factor for endometrial cancer, evidence linking risk to height, weight change since age 20, and physical activity is limited. In this case-cohort study, 62 573 women from The Netherlands Cohort Study on Diet and Cancer were followed up from 1986 to 1995, and

Historical cohort study of in utero exposure to uterotonic drugs and cognitive function in young adult life

DEFF Research Database (Denmark)

Sørensen, Henrik Toft; Steffensen, Flemming Hald; Sabroe, Svend

1999-01-01

Objective To examine whether in utero exposure to uterotonic drugs effects cognitive performance in draft-age men. Design Historical cohort study based on birth registry data and cognitive function measured during evaluations for military service. Subjects 4300 Danish conscripts born between 1973...... and those not exposed (n=3289), 43.1 versus 42.9 after adjustment for confounders. Conclusion Our data indicate that exposure to uterotonic drugs does not affect cognitive function 20 years later....

Designs for mechanical circulatory support device studies.

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Neaton, James D; Normand, Sharon-Lise; Gelijns, Annetine; Starling, Randall C; Mann, Douglas L; Konstam, Marvin A

2007-02-01

There is increased interest in mechanical circulatory support devices (MCSDs), such as implantable left ventricular assist devices (LVADs), as "destination" therapy for patients with advanced heart failure. Because patient availability to evaluate these devices is limited and randomized trials have been slow in enrolling patients, a workshop was convened to consider designs for MCSD development including alternatives to randomized trials. A workshop was jointly planned by the Heart Failure Society of America and the US Food and Drug Administration and was convened in March 2006. One of the panels was asked to review different designs for evaluating new MCSDs. Randomized trials have many advantages over studies with no controls or with nonrandomized concurrent or historical controls. These advantages include the elimination of bias in the assignment of treatments and the balancing, on average, of known and unknown baseline covariates that influence response. These advantages of randomization are particularly important for studies in which the treatments may not differ from one another by a large amount (eg, a head-to-head study of an approved LVAD with a new LVAD). However, researchers have found it difficult to recruit patients to randomized studies because the number of clinical sites that can carry out the studies is not large. Also, there is a reluctance to randomize patients when the control device is considered technologically inferior. Thus ways of improving the design of randomized trials were discussed, and the advantages and disadvantages of alternative designs were considered. The panel concluded that designs should include a randomized component. Randomized designs might be improved by allowing the control device to be chosen before randomization, by first conducting smaller vanguard studies, and by allowing crossovers in trials with optimal medical management controls. With use of data from completed trials, other databases, and registries, alternative

Course of bereavement over 8-10 years in first degree relatives and spouses of people who committed suicide : longitudinal community based cohort study

NARCIS (Netherlands)

de Groot, Marieke; Kollen, Boudewijn J.

2013-01-01

Objective To identify factors predicting the long term course of complicated grief, depression, and suicide ideation in a community based sample of relatives bereaved through suicide. Design Longitudinal cohort study. Included in the multilevel regression models were sociodemographic and personality

Course of bereavement over 8-10 years in first degree relatives and spouses of people who committed suicide: longitudinal community based cohort study

NARCIS (Netherlands)

de Groot, M.; Kollen, B.J.

2013-01-01

Objective To identify factors predicting the long term course of complicated grief, depression, and suicide ideation in a community based sample of relatives bereaved through suicide. Design Longitudinal cohort study. Included in the multilevel regression models were sociodemographic and personality

Incense use and respiratory tract carcinomas: a prospective cohort study

DEFF Research Database (Denmark)

Yuan, J.M.; Wang, R.; Koh, W.P.

2008-01-01

of cancer and ages 45 to 74 years completed a comprehensive interview regarding living conditions and dietary and lifestyle factors. Through linkage to population-based registries, the cohort was followed through 2005 and cancer occurrence determined. The relative risk for these cancers associated......BACKGROUND: Incense use is an integral part of daily life in large parts of Asia. The burning of incense is a powerful producer of particulate matter and the smoke contains a multitude of well-characterized carcinogens. However, to the authors' knowledge, no convincing association has been reported...... between exposure to incense smoke and the development of cancer. Therefore, the relation between incense use and the risk of respiratory tract carcinomas was analyzed in a prospective cohort study. METHODS: Between 1993 and 1998, a population-based cohort of 61,320 Singapore Chinese who were free...

A Cohort Study on Meniscal Lesions among Airport Baggage Handlers

DEFF Research Database (Denmark)

Mikkelsen, Sigurd; Brauer, Charlotte; Pedersen, Ellen Bøtker

2016-01-01

socioeconomic background and less knee-straining work. Baggage handlers lifted suitcases with an average weight of approximately 15 kg, in total approximately five tonnes during a 9-hour workday. The cohort was followed in the National Patient Register and Civil Registration System. The outcome was a first time......Meniscal lesions are common and may contribute to the development of knee arthrosis. A few case-control and cross-sectional studies have identified knee-straining work as risk factors for meniscal lesions, but exposure-response relations and the role of specific exposures are uncertain...... of unskilled men employed at Copenhagen Airport or in other companies in the metropolitan Copenhagen area from 1990 to 2012 (the Copenhagen Airport Cohort). The cohort at risk included 3,307 airport baggage handlers with heavy lifting and kneeling or squatting work tasks and 63,934 referents with a similar...

Establishing a birth cohort to investigate the course and aetiology of asthma and allergies across three generations - rationale, design, and methods of the ACROSSOLAR study.

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Weinmann, Tobias; Gerlich, Jessica; Heinrich, Sabine; Nowak, Dennis; Gerdes, Jennifer; Schlichtiger, Jenny; von Mutius, Erika; Schaub, Bianca; Vogelberg, Christian; Roller, Diana; Radon, Katja

2015-12-04

Atopic diseases are a major burden of disease on a global scale. Regarding their aetiology, the early years of life are assumed to play a crucial role. In addition, there is growing evidence that elucidating the impact of cross-generational effects and epigenetic mechanisms such as DNA methylation can substantially widen the scientific knowledge of the occurrence and progression of these diseases. We are thus aiming at following the course of asthma, allergies, and potential risk factors for their occurrence across three generations by establishing a birth cohort in the offspring of an existing population-based cohort. 2051 young adults who have been recruited in 1995 for Phase II of the International Study of Asthma and Allergies in Childhood (ISAAC) and who have subsequently been followed-up by the Study on Occupational Allergy Risks (SOLAR) are asked bi-annually since 2009 if they conceived a child in the meantime. If parenthood is reported, parents are invited to enrol along with their children in the ACROSSOLAR cohort. Participation involves completing a questionnaire assessing general and health-related information about the course of the pregnancy and the first year of life of their children. Subsequently, the children are followed up until primary school age when asthma and allergies can be diagnosed reliably. In addition, DNA for epigenetic analysis will be collected and analysed. Longitudinal data analysis techniques will then be used to assess potential associations between early-life exposures and onset of childhood asthma and allergies taking into account epigenetics. Birth cohorts are especially suited to elucidate the impact of genetic predisposition, epigenetics, exposures during the first years of life, and gene-environment interactions on the occurrence and progression of asthma and allergies. By building upon an existing cohort, ACROSSOLAR offers a unique and cost-effective opportunity to investigate the aetiology of atopic disease in a

Promotoras Can Facilitate Use of Recreational Community Resources: The Mi Corazón Mi Comunidad Cohort Study.

Science.gov (United States)

Balcázar, Héctor G; de Heer, Hendrik D; Wise Thomas, Sherrie; Redelfs, Alisha; Rosenthal, E Lee; Burgos, Ximena; Duarte, Maria O

2016-05-01

Limited research has documented interventions aimed at promoting use of existing recreational community resources among underserved populations. This study (HEART [Health Education Awareness Research Team] Phase 2) reports findings of an intervention (Mi Corazón Mi Comunidad) where community health workers facilitated use of diet and exercise programming at local recreational facilities among Mexican American border residents. The aim was to evaluate overall attendance rates and to assess which factors predicted higher attendance. The design was a cohort study. From 2009 to 2013, a total of 753 participants were recruited across 5 consecutive cohorts. The intervention consisted of organized physical activity and nutrition programming at parks and recreational facilities and a free YWCA membership. Attendance at all activities was objectively recorded. Regression analyses were used to evaluate whether demographic factors, health status, and health beliefs were associated with attendance. Results Participants included mostly females at high risk for cardiovascular disease (72.4% were overweight/obese and 64% were [pre-]hypertensive). A total of 83.6% of participants attended at least one session. On average, total attendance was 21.6 sessions (range: 19.1-25.2 sessions between the different cohorts), including 16.4 physical activity and 5.2 nutrition sessions. Females (p = .003) and older participants (p benefits (p = .038), and healthy intentions (p = .024) were associated with higher attendance. Conclusions The intervention was successful in promoting use of recreational facilities among border residents at high risk for cardiovascular disease. Findings were similar across five different cohorts. © 2015 Society for Public Health Education.

Long-term exposure to ambient ozone and mortality: a quantitative systematic review and meta-analysis of evidence from cohort studies.

Science.gov (United States)

Atkinson, R W; Butland, B K; Dimitroulopoulou, C; Heal, M R; Stedman, J R; Carslaw, N; Jarvis, D; Heaviside, C; Vardoulakis, S; Walton, H; Anderson, H R

2016-02-23

While there is good evidence for associations between short-term exposure to ozone and a range of adverse health outcomes, the evidence from narrative reviews for long-term exposure is suggestive of associations with respiratory mortality only. We conducted a systematic, quantitative evaluation of the evidence from cohort studies, reporting associations between long-term exposure to ozone and mortality. Cohort studies published in peer-reviewed journals indexed in EMBASE and MEDLINE to September 2015 and PubMed to October 2015 and cited in reviews/key publications were identified via search strings using terms relating to study design, pollutant and health outcome. Study details and estimate information were extracted and used to calculate standardised effect estimates expressed as HRs per 10 ppb increment in long-term ozone concentrations. 14 publications from 8 cohorts presented results for ozone and all-cause and cause-specific mortality. We found no evidence of associations between long-term annual O3 concentrations and the risk of death from all causes, cardiovascular or respiratory diseases, or lung cancer. 4 cohorts assessed ozone concentrations measured during the warm season. Summary HRs for cardiovascular and respiratory causes of death derived from 3 cohorts were 1.01 (95% CI 1.00 to 1.02) and 1.03 (95% CI 1.01 to 1.05) per 10 ppb, respectively. Our quantitative review revealed a paucity of independent studies regarding the associations between long-term exposure to ozone and mortality. The potential impact of climate change and increasing anthropogenic emissions of ozone precursors on ozone levels worldwide suggests further studies of the long-term effects of exposure to high ozone levels are warranted. 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/

Treatment of pregnancy-related pelvic girdle and/or low back pain after delivery design of a randomized clinical trial within a comprehensive prognostic cohort study [ISRCTN08477490

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Klabbers Aldegonda BA

2004-12-01

Full Text Available Abstract Background Pregnancy-related pelvic girdle and/or low back pain is a controversial syndrome because insight in etiology and prognosis is lacking. The controversy relates to factors eliciting pain and some prognostic factors such as the interpretation of pain at the symphysis. Recent research about treatment strategies also reflects those various opinions, in fact suggesting there is professional uncertainty about the optimal approach. Currently, physiotherapists often prescribe a pain-contingent treatment regime of relative rest and avoiding several day-to-day activities. Additionally, treatment more often includes an exercise program to guide rectification of the muscle imbalance and alignment of the pelvic girdle. Effectiveness of those interventions is not proven and the majority of the studies are methodologically flawed. Investigators draw particular attention to biomedical factors but there is growing evidence that important prognostic issues such as biopsychosocial factors appear to be even more important as point of action in a treatment program. Methods/design This pragmatic randomized controlled trial is designed to evaluate the effectiveness of a tailor-made treatment program with respect to biopsychosocial factors in primary care. The effect of the experimental intervention and usual care are evaluated as they are applied in primary health care. The trial is embedded in a cohort study that is designed as a longitudinal, prospective study, which studies prevalence, etiology, severity and prognosis during pregnancy until one year after delivery. The present paper focuses on choices regarding recruitment procedures, in-/exclusion criteria and the development of a well-timed intervention. Discussion This section briefly discusses the actions taken to minimize bias in the design, the proper time-window for the experimental intervention and the contrast between the experimental intervention and usual care.

Academic Achievement in Primary School in Offspring Born to Mothers With Type 1 Diabetes (the EPICOM Study): A Register-Based Prospective Cohort Study

DEFF Research Database (Denmark)

Knorr, Sine; Clausen, Tine D; Vlachová, Zuzana

2015-01-01

OBJECTIVE: This study examined the effect of maternal pregestational type 1 diabetes on offspring primary school performance. RESEARCH DESIGN AND METHODS: We performed a prospective combined clinical and register-based cohort study comparing primary school performance in offspring (n = 707......) of women with pregestational type 1 diabetes with matched control offspring (n = 60,341). We also examined the association between HbA1c levels during pregnancy and later school performance among offspring born to women with pregestational type 1 diabetes. RESULTS: Offspring of mothers with pregestational...

The MOBILIZE Boston Study: Design and methods of a prospective cohort study of novel risk factors for falls in an older population

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Hannan Marian T

2008-07-01

Full Text Available Abstract Background Falls are the sixth leading cause of death in elderly people in the U.S. Despite progress in understanding risk factors for falls, many suspected risk factors have not been adequately studied. Putative risk factors for falls such as pain, reductions in cerebral blood flow, somatosensory deficits, and foot disorders are poorly understood, in part because they pose measurement challenges, particularly for large observational studies. Methods The MOBILIZE Boston Study (MBS, an NIA-funded Program Project, is a prospective cohort study of a unique set of risk factors for falls in seniors in the Boston area. Using a door-to-door population-based recruitment, we have enrolled 765 persons aged 70 and older. The baseline assessment was conducted in 2 segments: a 3-hour home interview followed within 4 weeks by a 3-hour clinic examination. Measures included pain, cerebral hemodynamics, and foot disorders as well as established fall risk factors. For the falls follow-up, participants return fall calendar postcards to the research center at the end of each month. Reports of falls are followed-up with a telephone interview to assess circumstances and consequences of each fall. A second assessment is performed 18 months following baseline. Results Of the 2382 who met all eligibility criteria at the door, 1616 (67.8% agreed to participate and were referred to the research center for further screening. The primary reason for ineligibility was inability to communicate in English. Results from the first 600 participants showed that participants are largely representative of seniors in the Boston area in terms of age, sex, race and Hispanic ethnicity. The average age of study participants was 77.9 years (s.d. 5.5 and nearly two-thirds were women. The study cohort was 78% white and 17% black. Many participants (39% reported having fallen at least once in the year before baseline. Conclusion Our results demonstrate the feasibility of conducting

Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

DEFF Research Database (Denmark)

Breckenkamp, Jürgen; Berg-Beckhoff, Gabriele; Münster, Eva

2009-01-01

, in addition, a cohort of amateur radio operators were considered. Based on expert ratings, literature reviews and our set of predefined criteria, three of the cohorts were identified as promising for further evaluation: the personnel (technicians) of medium/short wave broadcasting stations, amateur radio......BACKGROUND: The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF) in Germany. METHODS: A set of criteria was developed to evaluate the feasibility of such a cohort study...... and mixture of exposures, e.g. plastic vapours), although exposure was highest in this occupational setting. The advantage of the cohort of amateur radio operators was the large number of persons it includes, while the advantage of the cohort of personnel working at broadcasting stations was the quality...

Exclusion and Inclusion of Nonwhite Ethnic Minority Groups in 72 North American and European Cardiovascular Cohort Studies.

Directory of Open Access Journals (Sweden)

2006-01-01

Full Text Available BACKGROUND: Cohort studies are recommended for understanding ethnic disparities in cardiovascular disease. Our objective was to review the process for identifying, including, and excluding ethnic minority populations in published cardiovascular cohort studies in Europe and North America. METHODS AND FINDINGS: We found the literature using Medline (1966-2005, Embase (1980-2001, Cinahl, Web of Science, and citations from references; consultations with colleagues; Internet searches; and RB's personal files. A total of 72 studies were included, 39 starting after 1975. Decision-making on inclusion and exclusion of racial/ethnic groups, the conceptual basis of race/ethnicity, and methods of classification of racial/ethnic groups were rarely explicit. Few publications provided details on the racial/ethnic composition of the study setting or sample, and 39 gave no description. Several studies were located in small towns or in occupational settings, where ethnic minority populations are underrepresented. Studies on general populations usually had too few participants for analysis by race/ethnicity. Eight studies were explicitly on Caucasians/whites, and two excluded ethnic minority groups from the whole or part of the study on the basis of language or birthplace criteria. Ten studies were designed to compare white and nonwhite populations, while five studies focused on one nonwhite racial/ethnic group; all 15 of these were performed in the US. CONCLUSIONS: There is a shortage of information from cardiovascular cohort studies on racial/ethnic minority populations, although this has recently changed in the US. There is, particularly in Europe, an inequity resulting from a lack of research data in nonwhite populations. Urgent action is now required in Europe to address this disparity.

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.

Opium use and mortality in Golestan Cohort Study: prospective cohort study of 50,000 adults in Iran.

Science.gov (United States)

Khademi, Hooman; Malekzadeh, Reza; Pourshams, Akram; Jafari, Elham; Salahi, Rasool; Semnani, Shahryar; Abaie, Behrooz; Islami, Farhad; Nasseri-Moghaddam, Siavosh; Etemadi, Arash; Byrnes, Graham; Abnet, Christian C; Dawsey, Sanford M; Day, Nicholas E; Pharoah, Paul D; Boffetta, Paolo; Brennan, Paul; Kamangar, Farin

2012-04-17

To investigate the association between opium use and subsequent risk of death. Prospective cohort study. The Golestan Cohort Study in north-eastern Iran collected detailed validated data on opium use and other exposures at baseline. Participants were enrolled between January 2004 and June 2008 and were followed to May 2011, with a follow-up success rate of over 99%. 50,045 participants aged 40-75 at baseline. Mortality, all cause and major subcategories. 17% (n = 8487) of the participants reported opium use, with a mean duration of 12.7 years. During the follow-up period 2145 deaths were reported. The adjusted hazard ratio for all cause mortality associated with ever use of opium was 1.86 (95% confidence interval 1.68 to 2.06). Opium consumption was significantly associated with increased risks of deaths from several causes including circulatory diseases (hazard ratio 1.81) and cancer (1.61). The strongest associations were seen with deaths from asthma, tuberculosis, and chronic obstructive pulmonary disease (11.0, 6.22, and 5.44, respectively). After exclusion of people who self prescribed opium after the onset of major chronic illnesses, the associations remained strong with a dose-response relation. Opium users have an increased risk of death from multiple causes compared with non-users. Increased risks were also seen in people who used low amounts of opium for a long period and those who had no major illness before use.

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

Perceived stress and risk of colorectal cancer in men and women: a prospective cohort study

DEFF Research Database (Denmark)

Nielsen, N R; Kristensen, T S; Strandberg-Larsen, Katrine

2008-01-01

OBJECTIVE: We aim to assess the relationship between stress and risk of primary colorectal cancer in men and women. DESIGN: A prospective cohort study. SETTING: The Copenhagen City Heart Study, Denmark. SUBJECTS: A total of 6488 women and 5426 men were included in the study. The participants were...... there was no clear relationship between stress and colorectal cancer in men....... asked about intensity and frequency of stress at baseline in 1981-1983 and were followed until the end of 2000 in the Danish Cancer Registry. Less than 0.1% was lost to follow-up. MAIN OUTCOME MEASURES: First time incidence of primary colorectal cancer. RESULTS: During follow-up 162 women and 166 men...

Cohort study of atypical pressure ulcers development.

Science.gov (United States)

Jaul, Efraim

2014-12-01

Atypical pressure ulcers (APU) are distinguished from common pressure ulcers (PU) with both unusual location and different aetiology. The occurrence and attempts to characterise APU remain unrecognised. The purpose of this cohort study was to analyse the occurrence of atypical location and the circumstances of the causation, and draw attention to the prevention and treatment by a multidisciplinary team. The cohort study spanned three and a half years totalling 174 patients. The unit incorporates two weekly combined staff meetings. One concentrates on wound assessment with treatment decisions made by the physician and nurse, and the other, a multidisciplinary team reviewing all patients and coordinating treatment. The main finding of this study identified APU occurrence rate of 21% within acquired PU over a three and a half year period. Severe spasticity constituted the largest group in this study and the most difficult to cure wounds, located in medial aspects of knees, elbows and palms. Medical devices caused the second largest occurrence of atypical wounds, located in the nape of the neck, penis and nostrils. Bony deformities were the third recognisable atypical wound group located in shoulder blades and upper spine. These three categories are definable and time observable. APU are important to be recognisable, and can be healed as well as being prevented. The prominent role of the multidisciplinary team is primary in identification, prevention and treatment. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Intrapartum and neonatal mortality in primary midwife-led and secondary obstetrician-led care in the Amsterdam region of the Netherlands: A retrospective cohort study

NARCIS (Netherlands)

Wiegerinck, M.M.J.; van der Goes, B.Y.; Ravelli, A.C.J.; van der Post, J.A.M.; Klinkert, J.; Brandenbarg, J.; Buist, F.C.D.; Wouters, M.G.A.J.; Tamminga, P.; de Jonge, A.; Mol, B.W.

2015-01-01

Objective: to compare intrapartum- and neonatal mortality and intervention rates in term women starting labour in primary midwife-led versus secondary obstetrician-led care. Design: retrospective cohort study. Setting: Amsterdam region of the Netherlands. Participants: women with singleton

Moderators of the longitudinal relationship between the perceived physical environment and outside play in children: The KOALA birth cohort study

OpenAIRE

Remmers, T.; Kann, D. van; Gubbels, J.; Schmidt, S.; Vries, S. de; Ettema, D.; Kremers, S.P.J.; Thijs, C.

2014-01-01

Objectives: Promoting unstructured outside play is a promising vehicle to increase children’s physical activity (PA). This study investigates if factors of the social environment moderate the relationship between the perceived physical environment and outside play. Study design: 1875 parents from the KOALA Birth Cohort Study reported on their child’s outside play around age five years, and 1516 parents around age seven years. Linear mixed model analyses were performed to evaluate (moderating)...

No certain predictors for mutation status in a Danish cohort with familial hypercholesterolemia: a descriptive study

DEFF Research Database (Denmark)

Nybo, Mads; Brusgaard, Klaus; Hansen, Annebirthe Bo

2007-01-01

OBJECTIVE: In order to enable clinicians to refer the right persons suspected of familial hypercholesterolemia (FH) for mutation screening, a retrospective study was conducted in a Danish FH cohort. DESIGN AND METHODS: The study comprised 643 probands and 395 relatives, of which 421 individuals had...... a pathogenic mutation, and 211 had cardiovascular disease (CVD). Logistic regression, Cox regression, and receiver operating characteristics (ROC) curves were used to find optimal predictive variables for mutation status and evaluate risk factors for CVD. RESULTS: Age alone had significant predictive power...... criteria should therefore be referred in order to facilitate family tracing and genetic counseling...

Rationale and study design of the Japan environment and children's study (JECS).

Science.gov (United States)

Kawamoto, Toshihiro; Nitta, Hiroshi; Murata, Katsuyuki; Toda, Eisaku; Tsukamoto, Naoya; Hasegawa, Manabu; Yamagata, Zentaro; Kayama, Fujio; Kishi, Reiko; Ohya, Yukihiro; Saito, Hirohisa; Sago, Haruhiko; Okuyama, Makiko; Ogata, Tsutomu; Yokoya, Susumu; Koresawa, Yuji; Shibata, Yasuyuki; Nakayama, Shoji; Michikawa, Takehiro; Takeuchi, Ayano; Satoh, Hiroshi

2014-01-10

There is global concern over significant threats from a wide variety of environmental hazards to which children face. Large-scale and long-term birth cohort studies are needed for better environmental management based on sound science. The primary objective of the Japan Environment and Children's Study (JECS), a nation-wide birth cohort study that started its recruitment in January 2011, is to elucidate environmental factors that affect children's health and development. Approximately 100,000 expecting mothers who live in designated study areas will be recruited over a 3-year period from January 2011. Participating children will be followed until they reach 13 years of age. Exposure to environmental factors will be assessed by chemical analyses of bio-specimens (blood, cord blood, urine, breast milk, and hair), household environment measurements, and computational simulations using monitoring data (e.g. ambient air quality monitoring) as well as questionnaires. JECS' priority outcomes include reproduction/pregnancy complications, congenital anomalies, neuropsychiatric disorders, immune system disorders, and metabolic/endocrine system disorders. Genetic factors, socioeconomic status, and lifestyle factors will also be examined as covariates and potential confounders. To maximize representativeness, we adopted provider-mediated community-based recruitment. Through JECS, chemical substances to which children are exposed during the fetal stage or early childhood will be identified. The JECS results will be translated to better risk assessment and management to provide healthy environment for next generations.

Development and validation of risk prediction equations to estimate survival in patients with colorectal cancer: cohort study

OpenAIRE

Hippisley-Cox, Julia; Coupland, Carol

2017-01-01

Objective: To develop and externally validate risk prediction equations to estimate absolute and conditional survival in patients with colorectal cancer. \\ud \\ud Design: Cohort study.\\ud \\ud Setting: General practices in England providing data for the QResearch database linked to the national cancer registry.\\ud \\ud Participants: 44 145 patients aged 15-99 with colorectal cancer from 947 practices to derive the equations. The equations were validated in 15 214 patients with colorectal cancer ...

Trends in adolescent alcohol use: Effects of age, sex and cohort on prevalence and heritability

NARCIS (Netherlands)

Geels, L.M.; Bartels, M.; van Beijsterveldt, C.E.M.; Willemsen, G.; van der Aa, N.; Boomsma, D.I.; Vink, J.M.

2012-01-01

Aims To determine the effect of age, sex and cohort on the prevalence and genetic architecture of adolescent alcohol use (AAU). Design Survey study in participants registered with the Netherlands Twin Register. Setting Twins from the general population. Participants Two cohorts (data collected in

Sensor, a population-based cohort study on gastroenteritis in the Netherlands: incidence and etiology.

NARCIS (Netherlands)

Wit, M.A.S. de; Koopmans, M.P.G.; Kortbeek, L.M.; Wannet, W.J.B.; Vinje, J; Leusden, F. van; Bartelds, A.I.M.; Duynhoven, Y.T.H.P. van

2001-01-01

A prospective population-based cohort study with a nested case- control study was conducted to estimate the incidence of gastroenteritis and the associated pathogens in the general Dutch population. Follow-up of two consecutive cohorts was performed by weekly reporting cards from december 1998 to

Depression and young age impact on hip fracture subsequent to stroke: A population-based cohort study.

Science.gov (United States)

Yeh, Hui-Fang; Hsu, Yao-Chun; Clinciu, Daniel L; Tung, Heng-Hsin; Yen, Yung-Chieh; Kuo, Hung-Chang

2018-06-03

The purpose of this study is to identify whether depression and other associated factors in stroke are related to subsequent hip fracture. There are very few studies that focus on depression and demographic impact on subsequent hip fracture after a stroke. This a retrospective cohort study design. The Taiwan Longitudinal Health Insurance Database between 1997 and 2010 was used. Two stroke patient cohorts were analysed: (1) depression within 1 year after newly diagnosed strokes; (2) without depression within 1 year after newly diagnosed strokes. Demographic characteristics, comorbidities, and hip fracture were compared using the Fine and Gray regression model for subdistribution hazard ratios. Patients with depression showed a higher risk of hip fracture (95% CI, 0.99-1.66). Depression was associated with increased risk of hip fracture for patients below 50 years old (95% CI, 1.45-7.34). Comorbidities and gender showed no significant correlation with hip fracture risk in the depressed or nondepressed groups. Poststroke depression was a significant contributor to hip fracture in patients who suffered strokes and had more negative impact on the younger population, regardless of the gender and presence of comorbidities. © 2018 John Wiley & Sons Australia, Ltd.

Shaping the ROTC Cohort

National Research Council Canada - National Science Library

Rittenhouse, Wiley P; Kwinn, Jr, Michael J

2005-01-01

...) - to meet the future needs of the Army for commissioned officers. It is designed to shape each cohort to meet the Army's specific needs in terms of component, academic disciplines, race/ethnic makeup goals, gender, and targeted missions...

Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

Directory of Open Access Journals (Sweden)

Wahrendorf Jürgen

2009-05-01

Full Text Available Abstract Background The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF in Germany. Methods A set of criteria was developed to evaluate the feasibility of such a cohort study. The criteria aimed at conditions of exposure and exposure assessment (level, duration, preferably on an individual basis, the possibility to assemble a cohort and the feasibility of ascertaining various disease endpoints. Results Twenty occupational settings with workers potentially exposed to RF-EMF and, in addition, a cohort of amateur radio operators were considered. Based on expert ratings, literature reviews and our set of predefined criteria, three of the cohorts were identified as promising for further evaluation: the personnel (technicians of medium/short wave broadcasting stations, amateur radio operators, and workers on dielectric heat sealers. After further analyses, the cohort of workers on dielectric heat sealers seems not to be feasible due to the small number of exposed workers available and to the difficulty of assessing exposure (exposure depends heavily on the respective working process and mixture of exposures, e.g. plastic vapours, although exposure was highest in this occupational setting. The advantage of the cohort of amateur radio operators was the large number of persons it includes, while the advantage of the cohort of personnel working at broadcasting stations was the quality of retrospective exposure assessment. However, in the cohort of amateur radio operators the exposure assessment was limited, and the cohort of technicians was hampered by the small number of persons working in this profession. Conclusion The majority of occupational groups exposed to RF-EMF are not practicable for setting up an occupational cohort study due to the small numbers of exposed subjects or due to exposure levels being only marginally higher

Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

Science.gov (United States)

2009-01-01

Background The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF) in Germany. Methods A set of criteria was developed to evaluate the feasibility of such a cohort study. The criteria aimed at conditions of exposure and exposure assessment (level, duration, preferably on an individual basis), the possibility to assemble a cohort and the feasibility of ascertaining various disease endpoints. Results Twenty occupational settings with workers potentially exposed to RF-EMF and, in addition, a cohort of amateur radio operators were considered. Based on expert ratings, literature reviews and our set of predefined criteria, three of the cohorts were identified as promising for further evaluation: the personnel (technicians) of medium/short wave broadcasting stations, amateur radio operators, and workers on dielectric heat sealers. After further analyses, the cohort of workers on dielectric heat sealers seems not to be feasible due to the small number of exposed workers available and to the difficulty of assessing exposure (exposure depends heavily on the respective working process and mixture of exposures, e.g. plastic vapours), although exposure was highest in this occupational setting. The advantage of the cohort of amateur radio operators was the large number of persons it includes, while the advantage of the cohort of personnel working at broadcasting stations was the quality of retrospective exposure assessment. However, in the cohort of amateur radio operators the exposure assessment was limited, and the cohort of technicians was hampered by the small number of persons working in this profession. Conclusion The majority of occupational groups exposed to RF-EMF are not practicable for setting up an occupational cohort study due to the small numbers of exposed subjects or due to exposure levels being only marginally higher than those of the general

Vegetarianism, low meat consumption and the risk of colorectal cancer in a population based cohort study

NARCIS (Netherlands)

Gilsing, A.M.J.; Schouten, L.J.; Goldbohm, R.A.; Dagnelie, P.C.; Brandt, P.A. van den; Weijenberg, M.P.

2015-01-01

To study how a vegetarian or low meat diet influences the risk of colorectal cancer compared to a high meat diet, and to assess the explanatory role of factors associated with these diets. In the Netherlands Cohort Study – Meat Investigation Cohort (NLCS-MIC) (cohort of 10,210 individuals including

VTE Risk assessment – a prognostic Model: BATER Cohort Study of young women

Directory of Open Access Journals (Sweden)

Schürmann Rolf

2005-04-01

Full Text Available Abstract Background Community-based cohort studies are not available that evaluated the predictive power of both clinical and genetic risk factors for venous thromboembolism (VTE. There is, however, clinical need to forecast the likelihood of future occurrence of VTE, at least qualitatively, to support decisions about intensity of diagnostic or preventive measures. Materials and methods A 10-year observation period of the Bavarian Thromboembolic Risk (BATER study, a cohort study of 4337 women (18–55 years, was used to develop a predictive model of VTE based on clinical and genetic variables at baseline (1993. The objective was to prepare a probabilistic scheme that discriminates women with virtually no VTE risk from those at higher levels of absolute VTE risk in the foreseeable future. A multivariate analysis determined which variables at baseline were the best predictors of a future VTE event, provided a ranking according to the predictive power, and permitted to design a simple graphic scheme to assess the individual VTE risk using five predictor variables. Results Thirty-four new confirmed VTEs occurred during the observation period of over 32,000 women-years (WYs. A model was developed mainly based on clinical information (personal history of previous VTE and family history of VTE, age, BMI and one composite genetic risk markers (combining Factor V Leiden and Prothrombin G20210A Mutation. Four levels of increasing VTE risk were arbitrarily defined to map the prevalence in the study population: No/low risk of VTE (61.3%, moderate risk (21.1%, high risk (6.0%, very high risk of future VTE (0.9%. In 10.6% of the population the risk assessment was not possible due to lacking VTE cases. The average incidence rates for VTE in these four levels were: 4.1, 12.3, 47.2, and 170.5 per 104 WYs for no, moderate, high, and very high risk, respectively. Conclusion Our prognostic tool – containing clinical information (and if available also genetic data

The effect of gender medicine education in GP training: a prospective cohort study.

Science.gov (United States)

Dielissen, Patrick; Verdonk, Petra; Waard, Magreet Wieringa-de; Bottema, Ben; Lagro-Janssen, Toine

2014-11-01

The purpose of this study is to compare the change in general practitioner (GP) trainees' gender awareness following a modular gender medicine programme or a mainstream gender medicine programme. In 2007, a prospective study was conducted in three cohorts of in total 207 GP trainees who entered GP training in the Netherlands. The outcome measure was the Nijmegen Gender Awareness in Medicine Scale and a 16-item gender knowledge questionnaire. Two gender medicine teaching methods were compared: a modular approach (n = 75) versus a mainstream approach (n = 72). Both strategies were compared with a control cohort (n = 60). Statistical analysis included analysis of variance and t-tests. The overall response rates for the modular, mainstream and control cohort were 78, 72 and 82 %, respectively. There was a significant difference in change in gender knowledge scores between the modular cohort compared with the mainstream and control cohort (p = 0.049). There were no statistical differences between the cohorts on gender sensitivity and gender role ideology. At entry and end, female GP trainees demonstrated significantly higher gender awareness than male GP trainees. A modular teaching method is not a more favourable educational method to teach gender medicine in GP training. Female GP trainees are more gender aware, but male GP trainees are not unaware of gender-related issues.

Termination of pregnancy among very preterm births and its impact on very preterm mortality : results from ten European population-based cohorts in the MOSAIC study

NARCIS (Netherlands)

Papiernik, E.; Zeitlin, J.; Delmas, D.; Draper, E. S.; Gadzinowski, J.; Kuenzel, W.; Cuttini, M.; Di Lallo, D.; Weber, T.; Kollee, L.; Bekaert, A.; Breart, G.

Objective To study the impact of terminations of pregnancy (TOP) on very preterm mortality in Europe. Design European prospective population-based cohort study. Setting Ten regions from nine European countries participating in the MOSAIC (Models of OrganiSing Access to Intensive Care for very

Effects of physical activity calorie expenditure (PACE) labeling: study design and baseline sample characteristics.

Science.gov (United States)

Viera, Anthony J; Tuttle, Laura; Olsson, Emily; Gras-Najjar, Julie; Gizlice, Ziya; Hales, Derek; Linnan, Laura; Lin, Feng-Chang; Noar, Seth M; Ammerman, Alice

2017-09-12

Obesity and physical inactivity are responsible for more than 365,000 deaths per year and contribute substantially to rising healthcare costs in the US, making clear the need for effective public health interventions. Calorie labeling on menus has been implemented to guide consumer ordering behaviors, but effects on calories purchased has been minimal. In this project, we tested the effect of physical activity calorie expenditure (PACE) food labels on actual point-of-decision food purchasing behavior as well as physical activity. Using a two-group interrupted time series cohort study design in three worksite cafeterias, one cafeteria was assigned to the intervention condition, and the other two served as controls. Calories from food purchased in the cafeteria were assessed by photographs of meals (accompanied by notes made on-site) using a standardized calorie database and portion size-estimation protocol. Primary outcomes will be average calories purchased and minutes of moderate to vigorous physical activity (MVPA) by individuals in the cohorts. We will compare pre-post changes in study outcomes between study groups using piecewise generalized linear mixed model regressions (segmented regressions) with a single change point in our interrupted time-series study. The results of this project will provide evidence of the effectiveness of worksite cafeteria menu labeling, which could potentially inform policy intervention approaches. Labels that convey information in a more readily understandable manner may be more effective at motivating behavior change. Strengths of this study include its cohort design and its robust data capture methods using food photographs and accelerometry.

Adaptation During a Great Economic Recession: A Cohort Study of Greek and Immigrant Youth.

Science.gov (United States)

Motti-Stefanidi, Frosso; Asendorpf, Jens B

2017-07-01

This study examined how Greek and immigrant youth adapted to school life during the economic recession in Greece. Two cohorts of adolescents (M age  = 12.6 years) were compared, one assessed before the crisis and the other during the crisis (N = 1,057 and 1,052, respectively). Cohort findings were disaggregated by immigrant status, generation, and ethnic group. Crisis-cohort youth experienced more economic problems, displayed worse conduct, higher levels of absenteeism, and lower self-efficacy than precrisis youth. The cohorts did not differ in well-being, school engagement, and academic achievement. Most crisis-cohort groups showed a pervasive increase in conduct problems compared to the precrisis cohort. However, some of these groups also showed an increase in academic achievement. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

POlish-Norwegian Study (PONS): research on chronic non-communicable diseases in European high risk countries - study design.

Science.gov (United States)

Zatoński, Witold A; Mańczuk, Marta

2011-01-01

A large-scale population study of health and disease would represent the most powerful tool to address these important issues in Poland. The aim is to extensively survey the study population with respect to important factors related to health and wellbeing, and subsequently, the intention is to follow-up the population for important health outcomes, including the incidence and mortality of cancer, cardiovascular disease, and other major causes of morbidity and mortality. The infrastructure for establishing a large cohort of people in Poland is needed; therefore, the PONS (Polish-Norwegian Study) project represents an eff ort to establish such infrastructure. The PONS Study is enrolling individuals aged 45-64 years. Structured lifestyle and food frequency questionnaires are administered. Study participants undergo medical check-up, anthropometric measurements and provide blood and urine sample for long-term storage. Fasting glucose and lipids profile are checked in the laboratory. This report describes the design, justification and methodology of the presented prospective cohort study. Recruitment of participants began in September 2010, and by the end of 2011 it is planned to achieve a total of between 10,000 – 15,000 participants. The PONS study is the fi rst prospective cohort study with blood and urine collection ever conducted in Central and Eastern Europe. It will provide reliable new data on both established and emerging risk factors for several major chronic diseases in a range of different circumstances.

Risk factors and study designs used in research of youths' suicide behaviour-an epidemiological discussion with focus on level of evidence

DEFF Research Database (Denmark)

Christiansen, Erik; Larsen, Kim Juul; Agerbo, Esben

2014-01-01

to level of evidence (LoE). Methods: We searched PubMed and psycINFO in order to identify relevant individual studies. Results: We included 36 studies of children and youth on suicidal behaviour and ideation-many rank low on LoE. For suicide, cohort design was often used, and mental illness (depression......Introduction: Many different epidemiology study designs have been used to analyse risk factors for suicide behaviour. The purpose of this study was to obtain an insight into the current study design used in research on youths' risk factors for suicide behaviour and to rank the studies according......, substance abuse and severity of mental illness) was the most common risk factor. Cohort studies are ranked 2b, which is high according to LoE. For suicide attempts, survey was often used, and psychopathology, substance abuse and being exposed to suicidal behaviour were the most common risk factors...

HIV incidence and risk factors in Chinese young men who have sex with men--a prospective cohort study.

Directory of Open Access Journals (Sweden)

Zhenxin Dong

Full Text Available OBJECTIVES: To assess HIV incidence and its associated risk factors among young men who have sex with men (YMSM in urban areas, China. DESIGN: The study used a prospective cohort study design and standard diagnostic tests. METHODS: A twelve-month prospective cohort study was conducted among YMSM (18-25 years old in 8 large cities in China. The participants were recruited via snowball sampling. A total of 1102 HIV-negative YMSM completed baseline assessment, 878 YMSM participants completed 6-month follow-up, and 902 completed 12-month follow-up. HIV was screened by an enzyme-linked immunosorbent assay and confirmed with Western Blot. Syphilis was screened via rapid plasma reagent and confirmed by treponema pallidum particle agglutination assay. RESULTS: 78 HIV seroconversions were identified within 1168.4 person-year observations yielding an incidence rate of 6.7 per 100 person-years. HIV seroconversion was associated with non-student status (RR = 2.61, 90% CI = 1.3-5.26, low HIV transmission knowledge (RR = 8.87, 90% CI = 2.16-36.43, and syphilis infection (RR = 5.04, 90% CI = 2.57-9.90. CONCLUSIONS: Incidence of HIV among YMSM is high in urban areas of China. Interventions measures are required to contain the HIV epidemic within this population.

Complex regional pain syndrome 1 – the Swiss cohort study

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Perez Roberto SGM

2008-06-01

Full Text Available Abstract Background Little is known about the course of Complex Regional Pain Syndrome 1 and potential factors influencing the course of this disorder over time. The goal of this study is a to set up a database with patients suffering from suspected CRPS 1 in an initial stadium, b to perform investigations on epidemiology, diagnosis, prognosis, and socioeconomics within the database and c to develop a prognostic risk assessment tool for patients with CRPS 1 taking into account symptomatology and specific therapies. Methods/design Prospective cohort study. Patients suffering from a painful swelling of the hand or foot which appeared within 8 weeks after a trauma or a surgery and which cannot be explained by conditions that would otherwise account for the degree of pain and dysfunction will be included. In accordance with the recommendations of International Classification of Functioning, Disability and Health (ICF model, standardised and validated questionnaires will be used. Patients will be monitored over a period of 2 years at 6 scheduled visits (0 and 6 weeks, 3, 6, 12, and 24 months. Each visit involves a physical examination, registration of therapeutic interventions, and completion of the various study questionnaires. Outcomes involve changes in health status, quality of life and costs/utility. Discussion This paper describes the rationale and design of patients with CRPS 1. Ideally, potential risk factors may be identified at an early stage in order to initiate an early and adequate treatment in patients with increased risk for delayed recovery. Trial registration Not applicable

Air pollution exposure estimation using dispersion modelling and continuous monitoring data in a prospective birth cohort study in the Netherlands

Directory of Open Access Journals (Sweden)

Van den Hooven Edith H

2012-02-01

Full Text Available Abstract Previous studies suggest that pregnant women and children are particularly vulnerable to the adverse effects of air pollution. A prospective cohort study in pregnant women and their children enables identification of the specific effects and critical periods. This paper describes the design of air pollution exposure assessment for participants of the Generation R Study, a population-based prospective cohort study from early pregnancy onwards in 9778 women in the Netherlands. Individual exposures to PM10 and NO2 levels at the home address were estimated for mothers and children, using a combination of advanced dispersion modelling and continuous monitoring data, taking into account the spatial and temporal variation in air pollution concentrations. Full residential history was considered. We observed substantial spatial and temporal variation in air pollution exposure levels. The Generation R Study provides unique possibilities to examine effects of short- and long-term air pollution exposure on various maternal and childhood outcomes and to identify potential critical windows of exposure.

E3N, a French cohort study on cancer risk factors. E3N Group. Etude Epidémiologique auprès de femmes de l'Education Nationale.

Science.gov (United States)

Clavel-Chapelon, F; van Liere, M J; Giubout, C; Niravong, M Y; Goulard, H; Le Corre, C; Hoang, L A; Amoyel, J; Auquier, A; Duquesnel, E

1997-10-01

This paper describes the design of E3N, a prospective cohort study conducted in France on risk factors for female cancers. The cohort comprises 100,000 women, aged 40-65 years at baseline in 1990. Participants were asked to complete questionnaires every 18 months. The main hypotheses studied concern the relationship between diet and cancer and between hormonal treatments and cancer. All cancers diagnosed are registered, together with other diseases (cardiovascular diseases, diabetes, osteoporosis). The study population and the follow-up procedure are described.

Open Access in Higher Education–Strategies for Engaging Diverse Student Cohorts

OpenAIRE

Signor, Luisa; Moore, Catherine

2014-01-01

With growth in online education, students gain tertiary qualifications through a mode more suited to their demographics such as work and life balance, learning styles and geographical accessibility. Inevitably this has led to a growth in diversity within student cohorts.The case study described in this paper illustrates strategies based on informed learning design for educating diverse student cohorts in an online program offered by Swinburne University of Technology. The case, an open-access...

The Danish National Cohort Study (DANCOS)

DEFF Research Database (Denmark)

Helweg-Larsen, Karin; Kjøller, Mette; Davidsen, Michael

2003-01-01

This article gives an overview of a nationally representive public health research database in Denmark, the Danish National Cohort Study (DANCOS). DANCOS combines baseline data from health interview surveys with both pre- and post-baseline data from national health registries with date from a re...... and administrative registries. All respondents and non-respondents were followed through 2002, a total of 3,796 had died and 249 had emigrated. The specific cause of death for 2,485 people was recorded in the Danish Register of Causes of Death, updated through 1998. For 1978-1977, the Danish National Hospital...

Folic acid knowledge and use in a multi-ethnic pregnancy cohort: the role of language proficiency

NARCIS (Netherlands)

van Eijsden, M.; van der Wal, M. F.; Bonsel, G. J.

2006-01-01

OBJECTIVE: To investigate the role of language proficiency as determinant of folic acid knowledge and use in a multi-ethnic pregnancy cohort. DESIGN: Prospective cohort study. SETTING AND POPULATION: Pregnant women from Amsterdam attending obstetric care for their first antenatal visit. Number

A case-control study of employment status and mortality in a cohort of Australian youth.

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Morrell, S; Taylor, R; Quine, S; Kerr, C; Western, J

1999-08-01

Recent studies have demonstrated a link in young populations between unemployment and ill health. The purpose of this study is to correlate mortality with employment status in two cohorts of young Australian males, aged 17-25 years, from 1984 to 1988. Two youth cohorts consisting of an initially unemployed sample (n = 1424 males) and a population sample (n = 4573 males), were surveyed annually throughout the study period. Those lost to follow-up during the survey period were matched with death registries across Australia. Employment status was determined from weekly diaries and death certificates and was designated as: employed or student; unemployed; not in the work force (excluding students). Conditional logistic regression, using age- and cohort- matched cases (deaths) and controls (alive), was used to estimate the odds ratio (OR) of dying with regard to employment status, taking into account potential confounders such as ethnicity, aboriginality, educational attainment, pre-existing health problems, socio-economic status of parents, and other factors. Twenty three male survey respondents were positively matched to death registry records. Compared to those employed or students (referent group), significantly elevated ORs were found to be associated with neither being in the workforce nor a student for all cause, external cause, and external cause mortality other than suicide. Odds ratios were adjusted for age, survey cohort, ethnicity, pre-existing physical and mental health status, education level, and socio-economic status of parent(s). A statistically significant increasing linear trend in odds ratios of male mortality for most cause groups was found across the employment categories, from those employed or student (lowest ORs), through those unemployed, to those not in the workforce (highest ORs). Suicide was higher, but not statistically significantly, in those unemployed or not in the workforce. Suicide also was associated, though not significantly, with

Nordic registry-based cohort studies: Possibilities and pitfalls when combining Nordic registry data.

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Maret-Ouda, John; Tao, Wenjing; Wahlin, Karl; Lagergren, Jesper

2017-07-01

All five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) have nationwide registries with similar data structure and validity, as well as personal identity numbers enabling linkage between registries. These resources provide opportunities for medical research that is based on large registry-based cohort studies with long and complete follow-up. This review describes practical aspects, opportunities and challenges encountered when setting up all-Nordic registry-based cohort studies. Relevant articles describing registries often used for medical research in the Nordic countries were retrieved. Further, our experiences of conducting this type of study, including planning, acquiring permissions, data retrieval and data cleaning and handling, and the possibilities and challenges we have encountered are described. Combining data from the Nordic countries makes it possible to create large and powerful cohorts. The main challenges include obtaining all permissions within each country, usually in the local language, and retrieving the data. These challenges emphasise the importance of having experienced collaborators within each country. Following the acquisition of data, data management requires the understanding of the differences between the variables to be used in the various countries. A concern is the long time required between initiation and completion. Nationwide Nordic registries can be combined into cohorts with high validity and statistical power, but the considerable expertise, workload and time required to complete such cohorts should not be underestimated.

The Study on Mental Health at Work: Design and sampling.

Science.gov (United States)

Rose, Uwe; Schiel, Stefan; Schröder, Helmut; Kleudgen, Martin; Tophoven, Silke; Rauch, Angela; Freude, Gabriele; Müller, Grit

2017-08-01

The Study on Mental Health at Work (S-MGA) generates the first nationwide representative survey enabling the exploration of the relationship between working conditions, mental health and functioning. This paper describes the study design, sampling procedures and data collection, and presents a summary of the sample characteristics. S-MGA is a representative study of German employees aged 31-60 years subject to social security contributions. The sample was drawn from the employment register based on a two-stage cluster sampling procedure. Firstly, 206 municipalities were randomly selected from a pool of 12,227 municipalities in Germany. Secondly, 13,590 addresses were drawn from the selected municipalities for the purpose of conducting 4500 face-to-face interviews. The questionnaire covers psychosocial working and employment conditions, measures of mental health, work ability and functioning. Data from personal interviews were combined with employment histories from register data. Descriptive statistics of socio-demographic characteristics and logistic regressions analyses were used for comparing population, gross sample and respondents. In total, 4511 face-to-face interviews were conducted. A test for sampling bias revealed that individuals in older cohorts participated more often, while individuals with an unknown educational level, residing in major cities or with a non-German ethnic background were slightly underrepresented. There is no indication of major deviations in characteristics between the basic population and the sample of respondents. Hence, S-MGA provides representative data for research on work and health, designed as a cohort study with plans to rerun the survey 5 years after the first assessment.

The Study on Mental Health at Work: Design and sampling

Science.gov (United States)

Rose, Uwe; Schiel, Stefan; Schröder, Helmut; Kleudgen, Martin; Tophoven, Silke; Rauch, Angela; Freude, Gabriele; Müller, Grit

2017-01-01

Aims: The Study on Mental Health at Work (S-MGA) generates the first nationwide representative survey enabling the exploration of the relationship between working conditions, mental health and functioning. This paper describes the study design, sampling procedures and data collection, and presents a summary of the sample characteristics. Methods: S-MGA is a representative study of German employees aged 31–60 years subject to social security contributions. The sample was drawn from the employment register based on a two-stage cluster sampling procedure. Firstly, 206 municipalities were randomly selected from a pool of 12,227 municipalities in Germany. Secondly, 13,590 addresses were drawn from the selected municipalities for the purpose of conducting 4500 face-to-face interviews. The questionnaire covers psychosocial working and employment conditions, measures of mental health, work ability and functioning. Data from personal interviews were combined with employment histories from register data. Descriptive statistics of socio-demographic characteristics and logistic regressions analyses were used for comparing population, gross sample and respondents. Results: In total, 4511 face-to-face interviews were conducted. A test for sampling bias revealed that individuals in older cohorts participated more often, while individuals with an unknown educational level, residing in major cities or with a non-German ethnic background were slightly underrepresented. Conclusions: There is no indication of major deviations in characteristics between the basic population and the sample of respondents. Hence, S-MGA provides representative data for research on work and health, designed as a cohort study with plans to rerun the survey 5 years after the first assessment. PMID:28673202

Perinatal and maternal outcomes by planned place of birth for healthy women with low risk pregnancies: the Birthplace in England national prospective cohort study.

NARCIS (Netherlands)

Brocklehurst, P.; Kwee, A.; Birthplace in England Collaborative Group

2011-01-01

Objective: To compare perinatal outcomes, maternal outcomes, and interventions in labour by planned place of birth at the start of care in labour for women with low risk pregnancies. Design: Prospective cohort study. Setting: England: all NHS trusts providing intrapartum care at home,

Locoregional first recurrence after mastectomy: prospective cohort studies with and without immediate chemotherapy

International Nuclear Information System (INIS)

Haylock, Brian J.; Coppin, Chris M.L.; Jackson, Jeremy; Basco, Vivien E.; Wilson, Kenneth S.

2000-01-01

Purpose: To evaluate prospectively the impact of combination chemotherapy in the combined modality treatment of isolated first locoregional recurrence (LRR) following mastectomy for breast cancer. Methods and Materials: Between 1979 and 1989, 120 chemotherapy-naive women with isolated LRR as first failure after mastectomy were prospectively identified, uniformly staged, and systematically followed. Treatment consisted of excision if feasible, radical locoregional radiotherapy, and a hormonal maneuver (unless estrogen receptor negative). The initial chemotherapy cohort also received 8 cycles of doxorubicin and cyclophosphamide. This was compared to a subsequent control cohort. Results: For all patients, the 10-year actuarial relapse-free survival ± 95% confidence interval was 42.1 ± 9.2%, and overall survival was 56.8 ± 9.1%. No difference was seen in locoregional control between cohorts. At 5 years, distant recurrence-free survival for chemotherapy and control cohort respectively was 75.4 ± 10.8% and 60.7 ±12.5% (p = 0.33) and overall survival was 81.9% ± 9.6 and 74.3% ± 11.2 (p = 0.24). Univariate analysis showed no prognostic importance for any imbalance between cohorts. Cox modeling confirmed that complete resection was strongly associated with fewer LRR (hazard ratio [HR] 0.32, p = 0.001) and also with better overall survival (HR 1.82, p = 0.019). Chemotherapy produced a substantial reduction in risk of death (HR 0.72 CI 0.421-1.235, p = 0.23). Conclusions: In this prospective but nonrandomized study of treatment for first LRR, the risk of death in the later control cohort was 1.39 times the risk in the chemotherapy cohort but failed to reach statistical significance. The results justify further study

The impact of attrition on the representativeness of cohort studies of older people

Directory of Open Access Journals (Sweden)

Brilleman Samuel L

2010-08-01

Full Text Available Abstract Background There are well-established risk factors, such as lower education, for attrition of study participants. Consequently, the representativeness of the cohort in a longitudinal study may deteriorate over time. Death is a common form of attrition in cohort studies of older people. The aim of this paper is to examine the effects of death and other forms of attrition on risk factor prevalence in the study cohort and the target population over time. Methods Differential associations between a risk factor and death and non-death attrition are considered under various hypothetical conditions. Empirical data from the Australian Longitudinal Study on Women's Health (ALSWH for participants born in 1921-26 are used to identify associations which occur in practice, and national cross-sectional data from Australian Censuses and National Health Surveys are used to illustrate the evolution of bias over approximately ten years. Results The hypothetical situations illustrate how death and other attrition can theoretically affect changes in bias over time. Between 1996 and 2008, 28.4% of ALSWH participants died, 16.5% withdrew and 10.4% were lost to follow up. There were differential associations with various risk factors, for example, non-English speaking country of birth was associated with non-death attrition but not death whereas being underweight (body mass index Conclusions Deaths occur in both the target population and study cohort, while other forms of attrition occur only in the study cohort. Therefore non-death attrition may cause greater bias than death in longitudinal studies. However although more than a quarter of the oldest participants in the ALSWH died in the 12 years following recruitment, differences from the national population changed only slightly.

Physical activity and influenza-coded outpatient visits, a population-based cohort study.

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Eric Siu

Full Text Available Although the benefits of physical activity in preventing chronic medical conditions are well established, its impacts on infectious diseases, and seasonal influenza in particular, are less clearly defined. We examined the association between physical activity and influenza-coded outpatient visits, as a proxy for influenza infection.We conducted a cohort study of Ontario respondents to Statistics Canada's population health surveys over 12 influenza seasons. We assessed physical activity levels through survey responses, and influenza-coded physician office and emergency department visits through physician billing claims. We used logistic regression to estimate the risk of influenza-coded outpatient visits during influenza seasons. The cohort comprised 114,364 survey respondents who contributed 357,466 person-influenza seasons of observation. Compared to inactive individuals, moderately active (OR 0.83; 95% CI 0.74-0.94 and active (OR 0.87; 95% CI 0.77-0.98 individuals were less likely to experience an influenza-coded visit. Stratifying by age, the protective effect of physical activity remained significant for individuals <65 years (active OR 0.86; 95% CI 0.75-0.98, moderately active: OR 0.85; 95% CI 0.74-0.97 but not for individuals ≥ 65 years. The main limitations of this study were the use of influenza-coded outpatient visits rather than laboratory-confirmed influenza as the outcome measure, the reliance on self-report for assessing physical activity and various covariates, and the observational study design.Moderate to high amounts of physical activity may be associated with reduced risk of influenza for individuals <65 years. Future research should use laboratory-confirmed influenza outcomes to confirm the association between physical activity and influenza.

Investing in Prospective Cohorts for Etiologic Study of Occupational Exposures

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Prospective cohorts have played a major role in understanding the role of diet, physical activity, medical conditions, and genes in the development of many diseases, but have not been widely used in the study of occupational exposures. Studies in agriculture are an exception. W...

A multinational clinical approach to assessing the effectiveness of catheter-based ultrasound renal denervation: The RADIANCE-HTN and REQUIRE clinical study designs.

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Mauri, Laura; Kario, Kazuomi; Basile, Jan; Daemen, Joost; Davies, Justin; Kirtane, Ajay J; Mahfoud, Felix; Schmieder, Roland E; Weber, Michael; Nanto, Shinsuke; Azizi, Michel

2018-01-01

Catheter-based renal denervation is a new approach to treat hypertension via modulation of the renal sympathetic nerves. Although nonrandomized and small, open-label randomized studies resulted in significant reductions in office blood pressure 6months after renal denervation with monopolar radiofrequency catheters, the first prospective, randomized, sham-controlled study (Symplicity HTN-3) failed to meet its blood pressure efficacy end point. New clinical trials with new catheters have since been designed to address the limitations of earlier studies. Accordingly, the RADIANCE-HTN and REQUIRE studies are multicenter, blinded, randomized, sham-controlled trials designed to assess the blood pressure-lowering efficacy of the ultrasound-based renal denervation system (Paradise) in patients with established hypertension either on or off antihypertensive medications, is designed to evaluate patients in 2 cohorts-SOLO and TRIO, in the United States and Europe. The SOLO cohort includes patients with essential hypertension, at low cardiovascular risk, and either controlled on 1 to 2 antihypertensive medications or uncontrolled on 0 to 2 antihypertensive medications. Patients undergo a 4-week medication washout period before randomization to renal denervation (treatment) or renal angiogram (sham). The TRIO cohort includes patients with hypertension resistant to at least 3 antihypertensive drugs including a diuretic. Patients will be stabilized on a single-pill, triple-antihypertensive-drug combination for 4weeks before randomization to treatment or sham. Reduction in daytime ambulatory systolic blood pressure (primary end point) will be assessed at 2months in both cohorts. A predefined medication escalation protocol, as needed for blood pressure control, is implemented between 2 and 6months in both cohorts by a study staff member blinded to the randomization process. At 6months, daytime ambulatory blood pressure and antihypertensive treatment score will be assessed. REQUIRE

Transcranial direct-current stimulation induced in stroke patients with aphasia: a prospective experimental cohort study

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Michele Devido Santos

Full Text Available CONTEXT AND OBJECTIVE: Previous animal and human studies have shown that transcranial direct current stimulation can induce significant and lasting neuroplasticity and may improve language recovery in patients with aphasia. The objective of the study was to describe a cohort of patients with aphasia after stroke who were treated with transcranial direct current stimulation. DESIGN AND SETTING: Prospective cohort study developed in a public university hospital. METHODS: Nineteen patients with chronic aphasia received 10 transcranial direct current stimulation sessions lasting 20 minutes each on consecutive days, using a current of 2 mA. The anode was positioned over the supraorbital area and the cathode over the contralateral motor cortex. The following variables were analyzed before and after the 10 neuromodulation sessions: oral language comprehension, copying, dictation, reading, writing, naming and verbal fluency. RESULTS: There were no adverse effects in the study. We found statistically significant differences from before to after stimulation in relation to simple sentence comprehension (P = 0.034, naming (P = 0.041 and verbal fluency for names of animals (P = 0.038. Improved scores for performing these three tasks were seen after stimulation. CONCLUSIONS: We observed that excitability of the primary motor cortex through transcranial direct current stimulation was associated with effects on different aspects of language. This can contribute towards future testing in randomized controlled trials.

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.

German new onset diabetes in the young incident cohort study: DiMelli study design and first-year results.

Science.gov (United States)

Thümer, Leonore; Adler, Kerstin; Bonifacio, Ezio; Hofmann, Frank; Keller, Manfred; Milz, Christine; Munte, Axel; Ziegler, Anette-Gabriele

2010-01-01

Diabetes incidence in childhood and youth is increasing worldwide, including autoimmune and non-autoimmune cases. Recent findings suggest that there is a larger than expected proportion of type 2 diabetes in youth, and potential cases of intermediate diabetes phenotypes. Most pediatric diabetes registries focus on type 1 diabetes. Also, there is an absence of reliable data on type 2 diabetes incidence in youth. The DiMelli study aims to establish a diabetes incidence cohort registry of patients in Germany, diagnosed with diabetes mellitus before age 20 years. It will be used to characterize diabetes phenotypes by immunologic, metabolic, and genetic markers. DiMelli will assess the contribution of obesity and socio-demographic factors to the development of diabetes in childhood and youth. Recruitment of patients started in 2009, and is expected to continue at a rate of 250 patients per year. 84% of the 216 patients recruited within the first year were positive for multiple islet autoantibodies, 12% for one islet autoantibody, and 4% were islet autoantibody-negative. Patients with multiple islet autoantibodies were younger and had lower fasting C-peptide levels, compared to islet autoantibody-negative patients (median age 10.0 vs. 14.1 years, p < 0.01). Results from the first year of the study show that DiMelli will help to reveal new knowledge on the etiology of diabetes, and the contribution of genetic predisposition and environmental risk factors to the different types of diabetes.

Early growth patterns and cardiometabolic function at the age of 5 in a multiethnic birth cohort: the ABCD study

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Vrijkotte Tanja GM

2009-03-01

Full Text Available Abstract Background The relation between fetal growth retardation and cardiovascular and metabolic diseases in later life has been demonstrated in many studies. However, debate exists around the potential independent role of postnatal growth acceleration. Furthermore, it is unknown whether a potential effect of growth acceleration on cardiovascular and metabolic function is confined to certain timeframes. The present study assesses the (predictive role of prenatal and postnatal growth on 5 components of cardiovascular and metabolic function in children aged 5. The potential association of timing of postnatal growth acceleration with these outcomes will be explored. Methods and design Prospective multiethnic community-based cohort study of 8266 pregnancies (Amsterdam Born Children and their Development, ABCD study. Up till now, anthropometry of 5104 children from the original cohort was followed during the first 5 years of life, with additional information about birth weight, pregnancy duration, and various potential confounding variables. At age 5, various components of cardiovascular and metabolic function are being measured. Outcome variables are body size, body composition and fat distribution, insulin sensitivity, lipid profile, blood pressure and autonomic regulation of cardiovascular function. Discussion This study will be one of the first population-based prospective cohort studies to address the association between measures of both prenatal and postnatal growth and various components of cardiovascular and metabolic function. Specific attention is paid to the timing of acceleration in growth and its potential association with the outcome variables. Importantly, the longitudinal design of this study gives us the opportunity to gain more insight into growth trajectories associated with adverse outcomes in later life. If identified as an independent risk factor, this provides further basis for the hypothesis that accelerated growth during

Unilateral Vocal Fold Paralysis and Risk of Pneumonia: A Nationwide Population-Based Cohort Study.

Science.gov (United States)

Tsai, Ming-Shao; Yang, Yao-Hsu; Liu, Chia-Yen; Lin, Meng-Hung; Chang, Geng-He; Tsai, Yao-Te; Li, Hsueh-Yu; Tsai, Ying-Huang; Hsu, Cheng-Ming

2018-05-01

Objective To investigate pneumonia risk among patients with unilateral vocal fold paralysis (UVFP). Study Design Retrospective population-based cohort study. Setting This study used data from the National Health Insurance Research Database of Taiwan, a nationwide population-based database. Subjects and Methods A total of 419 patients newly diagnosed with UVFP between January 1, 1997, and December 31, 2013, were identified from the Longitudinal Health Insurance Database 2000, a nationally representative database of 1 million randomly selected patients. Moreover, 1676 patients without UVFP were matched to patients with UVFP at a 1:4 ratio based on age, sex, socioeconomic status, urbanization level, and site-specific cancers. Patients were followed up until death or the end of the study period (December 31, 2013). The primary outcome was the occurrence of pneumonia. Results The cumulative incidence of pneumonia was significantly higher for patients with UVFP than those without UFVP ( P < .001). The adjusted Cox proportional hazard model showed that UVFP was significantly associated with a higher incidence of pneumonia (hazard ratio, 1.97; 95% CI, 1.35-2.86; P < .001). Subgroup analyses demonstrated that UVFP was an independent risk factor of pneumonia for 4 subgroups: young (18-50 years), older (≥51 years), male, and cancer. Conclusion This is the first nationwide population-based cohort study to investigate the association between UVFP and pneumonia. The findings indicate that UVFP is an independent risk factor of pneumonia. Given the study results, physicians should be aware of the potential for pneumonia occurrence following UVFP.

Dropout from exercise programs for seniors: A prospective cohort study

NARCIS (Netherlands)

Stiggelbout, M.; Hopman-Rock, M.; Tak, E.; Lechner, L.; Mechelen, W. van

2005-01-01

This study examines dropout incidence, moment of dropout, and switching behavior in organized exercise programs for seniors in the Netherlands, as determined in a prospective cohort study (with baseline measurements at the start of the exercise program and follow-up after 6 months; N = 1,725,

Prevalence and predictors of alcohol use during pregnancy: findings from international multicentre cohort studies.

Science.gov (United States)

O'Keeffe, Linda M; Kearney, Patricia M; McCarthy, Fergus P; Khashan, Ali S; Greene, Richard A; North, Robyn A; Poston, Lucilla; McCowan, Lesley M E; Baker, Philip N; Dekker, Gus A; Walker, James J; Taylor, Rennae; Kenny, Louise C

2015-07-06

To compare the prevalence and predictors of alcohol use in multiple cohorts. Cross-cohort comparison of retrospective and prospective studies. Population-based studies in Ireland, the UK, Australia and New Zealand. 17,244 women of predominantly Caucasian origin from two Irish retrospective studies (Growing up in Ireland (GUI) and Pregnancy Risk Assessment Monitoring System Ireland (PRAMS Ireland)), and one multicentre prospective international cohort, Screening for Pregnancy Endpoints (SCOPE) study. Prevalence of alcohol use pre-pregnancy and during pregnancy across cohorts. Sociodemographic factors associated with alcohol consumption in each cohort. Alcohol consumption during pregnancy in Ireland ranged from 20% in GUI to 80% in SCOPE, and from 40% to 80% in Australia, New Zealand and the UK. Levels of exposure also varied substantially among drinkers in each cohort ranging from 70% consuming more than 1-2 units/week in the first trimester in SCOPE Ireland, to 46% and 15% in the retrospective studies. Smoking during pregnancy was the most consistent predictor of gestational alcohol use in all three cohorts, and smokers were 17% more likely to drink during pregnancy in SCOPE, relative risk (RR)=1.17 (95% CI 1.12 to 1.22), 50% more likely to drink during pregnancy in GUI, RR=1.50 (95% CI 1.36 to 1.65), and 42% more likely to drink in PRAMS, RR=1.42 (95% CI 1.18 to 1.70). Our data suggest that alcohol use during pregnancy is prevalent and socially pervasive in the UK, Ireland, New Zealand and Australia. New policy and interventions are required to reduce alcohol prevalence both prior to and during pregnancy. Further research on biological markers and conventions for measuring alcohol use in pregnancy is required to improve the validity and reliability of prevalence estimates. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

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

The feasibility of matching on a propensity score for acupuncture in a prospective cohort study of patients with chronic pain

Directory of Open Access Journals (Sweden)

Eric S. Johnson

2017-03-01

scores to new patients, healthcare systems with electronic health records can conduct comparative effectiveness cohort studies that require prospective data collection, such as patient-reported outcomes, while approximately balancing numerous patient characteristics that might confound the benefit of an intervention. The approach offers a new study design option.

Risk of thyroid cancer in patients with thyroiditis: a population-based cohort study.

Science.gov (United States)

Liu, Chien-Liang; Cheng, Shih-Ping; Lin, Hui-Wen; Lai, Yuen-Liang

2014-03-01

The causative relationship between autoimmune thyroiditis and thyroid cancer remains a controversial issue. The aim of this population-based study was to investigate the risk of thyroid cancer in patients with thyroiditis. From the Longitudinal Health Insurance Database 2005 (LHID2005) of Taiwan, we identified adult patients newly diagnosed with thyroiditis between 2004 and 2009 (n = 1,654). The comparison cohort (n = 8,270) included five randomly selected age- and sex-matched controls for each patient in the study cohort. All patients were followed up from the date of cohort entry until they developed thyroid cancer or to the end of 2010. Multivariate Cox regression was used to assess the risk of developing thyroid cancer. A total of 1,000 bootstrap replicates were created for internal validation. A total of 35 patients developed thyroid cancer during the study period, of whom 24 were from the thyroiditis cohort and 11 were from the comparison cohort (incidence 353 and 22 per 100,000 person-years, respectively). After adjusting for potential confounding factors, the hazard ratio (HR) for thyroid cancer in patients with thyroiditis was 13.24 (95 % CI 6.40-27.39). Excluding cancers occurring within 1 year of follow-up, the HR remained significantly increased (6.64; 95 % CI 2.35-18.75). Hypothyroidism was not an independent factor associated with the occurrence of thyroid cancer. We found an increased risk for the development of thyroid cancer after a diagnosis of thyroiditis, independent of comorbidities.

Fish intake during pregnancy, fetal growth, and gestational length in 19 European birth cohort studies.

Science.gov (United States)

Leventakou, Vasiliki; Roumeliotaki, Theano; Martinez, David; Barros, Henrique; Brantsaeter, Anne-Lise; Casas, Maribel; Charles, Marie-Aline; Cordier, Sylvaine; Eggesbø, Merete; van Eijsden, Manon; Forastiere, Francesco; Gehring, Ulrike; Govarts, Eva; Halldórsson, Thorhallur I; Hanke, Wojciech; Haugen, Margaretha; Heppe, Denise H M; Heude, Barbara; Inskip, Hazel M; Jaddoe, Vincent W V; Jansen, Maria; Kelleher, Cecily; Meltzer, Helle Margrete; Merletti, Franco; Moltó-Puigmartí, Carolina; Mommers, Monique; Murcia, Mario; Oliveira, Andreia; Olsen, Sjúrður F; Pele, Fabienne; Polanska, Kinga; Porta, Daniela; Richiardi, Lorenzo; Robinson, Siân M; Stigum, Hein; Strøm, Marin; Sunyer, Jordi; Thijs, Carel; Viljoen, Karien; Vrijkotte, Tanja G M; Wijga, Alet H; Kogevinas, Manolis; Vrijheid, Martine; Chatzi, Leda

2014-03-01

Fish is a rich source of essential nutrients for fetal development, but in contrast, it is also a well-known route of exposure to environmental pollutants. We assessed whether fish intake during pregnancy is associated with fetal growth and the length of gestation in a panel of European birth cohort studies. The study sample of 151,880 mother-child pairs was derived from 19 population-based European birth cohort studies. Individual data from cohorts were pooled and harmonized. Adjusted cohort-specific effect estimates were combined by using a random- and fixed-effects meta-analysis. Women who ate fish >1 time/wk during pregnancy had lower risk of preterm birth than did women who rarely ate fish (≤ 1 time/wk); the adjusted RR of fish intake >1 but 1 but <3 times/wk and 15.2 g (95% CI: 8.9, 21.5 g) for ≥ 3 times/wk independent of gestational age. The association was greater in smokers and in overweight or obese women. Findings were consistent across cohorts. This large, international study indicates that moderate fish intake during pregnancy is associated with lower risk of preterm birth and a small but significant increase in birth weight.

Lack of Association Between Maternal or Neonatal Vitamin D Status and Risk of Childhood Type 1 Diabetes: A Scandinavian Case-Cohort Study.

Science.gov (United States)

Thorsen, Steffen U; Mårild, Karl; Olsen, Sjurdur F; Holst, Klaus K; Tapia, German; Granström, Charlotta; Halldorsson, Thorhallur I; Cohen, Arieh S; Haugen, Margaretha; Lundqvist, Marika; Skrivarhaug, Torild; Njølstad, Pål R; Joner, Geir; Magnus, Per; Størdal, Ketil; Svensson, Jannet; Stene, Lars C

2018-06-01

Studies on vitamin D status during pregnancy and risk of type 1 diabetes mellitus (T1D) lack consistency and are limited by small sample sizes or single measures of 25-hydroxyvitamin D (25(OH)D). We investigated whether average maternal 25(OH)D plasma concentrations during pregnancy are associated with risk of childhood T1D. In a case-cohort design, we identified 459 children with T1D and a random sample (n = 1,561) from the Danish National Birth Cohort (n = 97,127) and Norwegian Mother and Child Cohort Study (n = 113,053). Participants were born between 1996 and 2009. The primary exposure was the estimated average 25(OH)D concentration, based on serial samples from the first trimester until delivery and on umbilical cord plasma. We estimated hazard ratios using weighted Cox regression adjusting for multiple confounders. The adjusted hazard ratio for T1D per 10-nmol/L increase in the estimated average 25(OH)D concentration was 1.00 (95% confidence interval: 0.90, 1.10). Results were consistent in both cohorts, in multiple sensitivity analyses, and when we analyzed mid-pregnancy or cord blood separately. In conclusion, our large study demonstrated that normal variation in maternal or neonatal 25(OH)D is unlikely to have a clinically important effect on risk of childhood T1D.

Analysis of the bereavement effect after the death of a spouse in the Amish: a population-based retrospective cohort study

OpenAIRE

Seifter, Ari; Singh, Sarabdeep; McArdle, Patrick F; Ryan, Kathleen A; Shuldiner, Alan R; Mitchell, Braxton D; Schäffer, Alejandro A

2014-01-01

Objective This study investigates the association between bereavement and the mortality of a surviving spouse among Amish couples. We hypothesised that the bereavement effect would be relatively small in the Amish due to the unusually cohesive social structure of the Amish that might attenuate the loss of spousal support. Design Population-based cohort study. Setting The USA. Participants 10 892 Amish couples born during 1725–1900 located in Pennsylvania, Ohio and Indiana. All the participant...

pilot studies to test the feasibility of a birth cohort study investigating ...

African Journals Online (AJOL)

1991-04-20

Apr 20, 1991 ... of a birth cohort study investigating the effects of urbanisation in South Africa. S. FONN, M. DE ... is to determine the biological, environmental, economic and psychological factors that are associated with ... the South African Medical Research Council, Parowvallei,. CP. S. FONN, M.B. B.CH., D.O.H., D.EPL, ...

Presence and process of fear of birth during pregnancy-Findings from a longitudinal cohort study.

Science.gov (United States)

Hildingsson, Ingegerd; Haines, Helen; Karlström, Annika; Nystedt, Astrid

2017-10-01

The prevalence of fear of birth has been estimated between 8-30%, but there is considerable heterogeneity in research design, definitions, measurement tools used and populations. There are some inconclusive findings about the stability of childbirth fear. to assess the prevalence and characteristics of women presenting with scores ≥60 on FOBS-The Fear of Birth Scale, in mid and late pregnancy, and to study change in fear of birth and associated factors. A prospective longitudinal cohort study of a one-year cohort of 1212 pregnant women from a northern part of Sweden, recruited in mid pregnancy and followed up in late pregnancy. Fear of birth was assessed using FOBS-The fear of birth scale, with the cut off at ≥60. The prevalence of fear of birth was 22% in mid pregnancy and 19% in late pregnancy, a statistically significant decrease. Different patterns were found where some women presented with increased fear and some with decreased fear. The women who experienced more fear or less fear later in pregnancy could not be differentiated by background factors. More research is needed to explore factors important to reduce fear of childbirth and the optimal time to measure it. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

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

[Design and implementation of the ELSA-Brasil biobank: a prospective study in a Brazilian population].

Science.gov (United States)

Pereira, Alexandre C; Bensenor, Isabela M; Fedeli, Ligia M; Castilhos, Cristina; Vidigal, Pedro G; Maniero, Viviane; Leite, Claudia M; Pimentel, Robercia A; Duncan, Bruce B; Mill, Jose Geraldo; Lotufo, Paulo A

2013-06-01

The Brazilian Longitudinal Study for Adult Health (ELSA-Brasil) is a multicenter prospective cohort of civil servants designed to assess the determinants of chronic diseases, especially cardiovascular diseases and type 2 diabetes. The present article describes the main design and implementation points of the ELSA-Brasil biobank project. Economic, political, logistical and technological aspects of this study are characterized. Additionally, it discusses the final biorepository protocol and the facilities implemented to achieve this objective. The design and implementation process of the ELSA-Brasil biobank took three years to be performed. Both the central and local biobanks were built according to the best biorepository techniques, using different technological solutions for the distinct needs expected in this study.

Birth cohorts in Asia: The importance, advantages, and disadvantages of different-sized cohorts.

Science.gov (United States)

Kishi, Reiko; Araki, Atsuko; Minatoya, Machiko; Itoh, Sachiko; Goudarzi, Houman; Miyashita, Chihiro

2018-02-15

Asia contains half of the world's children, and the countries of Asia are the most rapidly industrializing nations on the globe. Environmental threats to the health of children in Asia are myriad. Several birth cohorts were started in Asia in early 2000, and currently more than 30 cohorts in 13 countries have been established for study. Cohorts can contain from approximately 100-200 to 20,000-30,000 participants. Furthermore, national cohorts targeting over 100,000 participants have been launched in Japan and Korea. The aim of this manuscript is to discuss the importance of Asian cohorts, and the advantages and disadvantages of different-sized cohorts. As for case, one small-sized (n=514) cohort indicate that even relatively low level exposure to dioxin in utero could alter birth size, neurodevelopment, and immune and hormonal functions. Several Asian cohorts focus prenatal exposure to perfluoroalkyo substances and reported associations with birth size, thyroid hormone levels, allergies and neurodevelopment. Inconsistent findings may possibly be explained by the differences in exposure levels and target chemicals, and by possible statistical errors. In a smaller cohort, novel hypotheses or preliminary examinations are more easily verifiable. In larger cohorts, the etiology of rare diseases, such as birth defects, can be analyzed; however, they require a large cost and significant human resources. Therefore, conducting studies in only one large cohort may not always be the best strategy. International collaborations, such as the Birth Cohort Consortium of Asia, would cover the inherent limitation of sample size in addition to heterogeneity of exposure, ethnicity, and socioeconomic conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

The Coordination and Activity Tracking in CHildren (CATCH) study: rationale and design.

Science.gov (United States)

Cairney, John; Missiuna, Cheryl; Timmons, Brian W; Rodriguez, Christine; Veldhuizen, Scott; King-Dowling, Sara; Wellman, Sarah; Le, Tuyen

2015-12-21

Past studies have found that children with Developmental Coordination Disorder (DCD) engage in less physical activity than typically developing children. This "activity deficit" may result in children with DCD being less physically fit and more likely to be overweight or obese, potentially increasing later risk for poor cardiovascular health. Unfortunately, the majority of DCD research has been limited to cross-sectional designs, leading to questions about the complex relationship among motor ability, inactivity and health-related fitness. Of the few longitudinal studies on the topic, determining precedence amongst these factors is difficult because study cohorts typically focus on mid to late childhood. By this age, both decreased physical fitness and obesity are often established. The Coordination and Activity Tracking in CHildren (CATCH) study will examine the pathways connecting DCD, physical activity, physical fitness, and body composition from early to middle childhood. The CATCH study is a prospective cohort study. We aim to recruit a cohort of 600 children aged 4 to 5 years (300 probable DCD [pDCD] and 300 controls) and test them once a year for 4 years. At Phase 1 of baseline testing, we assess motor skills, cognitive ability (IQ), basic anthropometry, flexibility and lower body muscle strength, while parents complete an interview and questionnaires regarding family demographics, their child's physical activity, and behavioural characteristics. Children who move on to Phase 2 (longitudinal cohort) have their body fat percentage, foot structure, aerobic and anaerobic fitness assessed. An accelerometer to measure physical activity is then given to the child and interested family members. The family also receives an accelerometer logbook and 3-day food dairy. At years 2 to 4, children in the longitudinal cohort will have all baseline assessments repeated (excluding the IQ test), and complete an additional measure of perceived self-efficacy. Parents will

Hyperthyroidism and female urinary incontinence: a population-based cohort study.

Science.gov (United States)

Chung, Shiu-Dong; Chen, Yi-Kuang; Chen, Yi-Hua; Lin, Herng-Ching

2011-11-01

The imbalanced autonomic nervous system present in hyperthyroidism may cause lower urinary tract symptoms. Urinary incontinence (UI) is the most bothersome lower urinary tract symptom; however, in the literature, reports regarding urinary dysfunction and/or incontinence among hyperthyroid patients are scarce. This population-based cohort study aimed to examine the relationship between hyperthyroidism in women and the risk of developing UI in Taiwan. This study used data from the Longitudinal Health Insurance Database. For this study, 10,817 female patients diagnosed with hyperthyroidism from 2001 to 2005 were recruited together with a comparison cohort of 54,085 matched enrollees who did not have a history of hyperthyroidism. All patients were tracked for a 3-year period from their index date to identify those who had a subsequent UI. The stratified Cox proportional hazards models were used to compute the risk of UI between study and comparison cohorts. During the follow-up period, of 64,169 patients, 173 (1·60%) from the hyperthyroidism group and 560 (1·04%) from the comparison group, had a diagnosis of UI. The regression analysis showed that, after adjusting for monthly income, geographic region, urbanization level of the community in which the patient resided, obesity and hysterectomy, patients with hyperthyroidism were more likely to have UI during the 3-year follow-up period than the comparison patients (hazard ratio = 1·54; 95% CI = 1·30-1·83; P hyperthyroidism at the 3-year follow-up. © 2011 Blackwell Publishing Ltd.

Association between diverticular disease and Ehlers-Danlos syndrome: a 13-year nationwide population-based cohort study.

Science.gov (United States)

Leganger, Julie; Søborg, Marie-Louise Kulas; Mortensen, Laura Quitzau; Gregersen, Rasmus; Rosenberg, Jacob; Burcharth, Jakob

2016-12-01

The aim of this study was to examine occurrence and consequences of diverticular disease in patients with Ehlers-Danlos syndrome (EDS) compared with a matched cohort. This nationwide population-based cohort study was conducted using data from medical registers in Denmark from year 2000 to 2012. The EDS cohort was identified using the specific diagnosis code for EDS and was randomly matched in a ratio of 1:20 by sex and date of birth (±1 year) with persons from the Danish general population. The occurrence of diverticular disease and the clinical characteristics of the initial diverticular event were compared between the EDS cohort and the comparison cohort. The first admission with diverticulitis was identified, and severity of diverticulitis, treatment, colonoscopies, length of stay, and 30-day mortality were investigated. We identified 1336 patients with EDS and matched a control cohort of 26,720 patients. The occurrence of diverticular disease in the EDS cohort (2.0 %) and the comparison cohort (0.68 %) differed significantly (p < 0.001). At the first diverticular event, the majority of patients were women (85 % for EDS and 87 % for the comparison cohort). Mean age, localization, and type of contact did not differ significantly. Admission with diverticulitis (1.0 % for EDS and 0.34 % for the comparison cohort) differed significantly (p < 0.001). We found no significant difference in severity of diverticulitis, treatment, length of stay, or 30-day mortality between the EDS and the comparison cohorts. Patients with EDS had an increased occurrence of overall diverticular events and admissions with diverticulitis compared with the general population.

Cohort-Sequential Study of Conflict Inhibition during Middle Childhood

Science.gov (United States)

Rollins, Leslie; Riggins, Tracy

2017-01-01

This longitudinal study examined developmental changes in conflict inhibition and error correction in three cohorts of children (5, 7, and 9 years of age). At each point of assessment, children completed three levels of Luria's tapping task (1980), which requires the inhibition of a dominant response and maintenance of task rules in working…

Computed tomography in children: multicenter cohort study design for the evaluation of cancer risk

International Nuclear Information System (INIS)

Krille, L.; Jahnen, A.; Mildenberger, P.; Schneider, K.; Weisser, G.; Zeeb, H.; Blettner, M.

2011-01-01

Exposure to ionizing radiation is a known risk factor for cancer. Cancer risk is highest after exposure in childhood. The computed tomography is the major contributor to the average, individual radiation exposure. Until now the association has been addressed only in statistical modeling. We present the first feasible study design on childhood cancer risk after exposure to computed tomography.

Workplace bullying, sleep problems and leisure-time physical activity: a prospective cohort study

DEFF Research Database (Denmark)

Hansen, Åse Marie; Gullander, Maria; Hogh, Annie

2015-01-01

and Harassment (WBH) cohort (N=3278) or the Psychosocial Risk Factors for Stress and Mental Disease (PRISME) cohort (N=4455). We measured workplace bullying using one question that was preceded by a definition of bullying. We used the Karolinska sleep questionnaire to assess sleep problems. The number of hours......OBJECTIVES: Workplace bullying is a potent stressor that may increase sleep problems. Since physical fitness improves resilience to stress, it seems plausible that recreational physical activities may moderate the association between bullying and sleep. The study aimed to examine prospectively...... whether (i) bullying increases the risk of sleep problems, and (ii) the association between bullying and sleep problems is moderated by leisure-time physical activity (LTPA). METHODS: The study sample comprised a cohort of public and private sector employees, who were enrolled into the Work Bullying...

Family history of psychiatric illness as a risk factor for schizoaffective disorder: a Danish register-based cohort study

DEFF Research Database (Denmark)

Laursen, Thomas Munk; Labouriau, Rodrigo; Licht, Rasmus Wentzer

2005-01-01

, or schizophrenia among parents and siblings is a risk factor for developing a schizoaffective disorder, and whether a specific pattern of family history of psychiatric illness exists in persons with schizoaffective disorder compared with persons with bipolar disorder or schizophrenia. DESIGN: Register-based cohort...... study. SETTING: Denmark. COHORT: The 2.4 million persons born in Denmark after 1952. MAIN OUTCOME MEASURES: Relative risks of the 3 illnesses estimated by Poisson regression. RESULTS: In total, 1925 persons had a schizoaffective disorder, 3721 had a bipolar disorder, and 12 501 had schizophrenia....... The relative risk of schizoaffective disorder was 2.76 (95% confidence interval, 2.49-3.06) if a first-degree relative had a history of mental illness compared with a person with no first-degree relatives with such a history. There was an additional risk (95% confidence interval) of 2.57 (2.11-3.13), 3.23 (2...

Risk of post-pregnancy hypertension in women with a history of hypertensive disorders of pregnancy: nationwide cohort study

OpenAIRE

Behrens, Ida; Basit, Saima; Melbye, Mads; Lykke, Jacob A; Wohlfahrt, Jan; Bundgaard, Henning; Thilaganathan, Baskaran; Boyd, Heather A

2017-01-01

Objectives To determine how soon after delivery the risk of post-pregnancy hypertension increases in women with hypertensive disorders of pregnancy and how the risk evolves over time.Design Nationwide register based cohort study.Setting Denmark.Populations 482 972 primiparous women with a first live birth or stillbirth between 1995 and 2012 (cumulative incidence analyses), and 1 025 118 women with at least one live birth or stillbirth between 1978 and 2012 (Cox regression analyses).Main outco...

Incidence of low- and high-energy fractures in persons with and without HIV-infection: a Danish population-based cohort study

DEFF Research Database (Denmark)

Hansen, Ann-Brit E; Gerstoft, Jan; Kronborg, Gitte

2012-01-01

significantly increased after HAART-exposure, IRR of 1.8 (95% CI; 1.5-2.1). The increased risk in HAART-exposed patients was not associated with CD4 cell count, prior AIDS, tenofovir or efavirenz exposure, but with comorbidity and smoking. CONCLUSIONS:: HIV-infected patients had increased risk of fracture......OBJECTIVE:: To compare fracture risk in persons with and without HIV-infection and to examine the influence of HAART initiation on risk of fracture. DESIGN:: Population-based nationwide cohort study using Danish registries. METHODS:: Outcome measures were time to first fracture at any site, time...... to first low-energy and high-energy fracture in HIV-infected patients (n¿=¿5,306) compared with a general population control cohort (n¿=¿26,530) matched by sex and age during the study period 1995 to 2009. Cox regression analyses were used to estimate incidence rate ratios (IRR). RESULTS:: HIV-infected...

Data linkage in an established longitudinal cohort: the Western Australian Pregnancy Cohort (Raine) Study.

Science.gov (United States)

Mountain, Jenny A; Nyaradi, Anett; Oddy, Wendy H; Glauert, Rebecca A; de Klerk, Nick H; Straker, Leon M; Stanley, Fiona J

2016-07-15

The Western Australian Data Linkage System is one of a few comprehensive, population-based data linkage systems worldwide, creating links between information from different sources relating to the same individual, family, place or event, while maintaining privacy. The Raine Study is an established cohort study with more than 2000 currently active participants. Individual consent was obtained from participants for information in publicly held databases to be linked to their study data. A waiver of consent was granted where it was impracticable to obtain consent. Approvals to link the datasets were obtained from relevant ethics committees and data custodians. The Raine Study dataset was subsequently linked to academic testing data collected by the Western Australian Department of Education. Examination of diet and academic performance showed that children who were predominantly breastfed for at least 6 months scored higher academically at age 10 than children who were breastfed for less than 6 months. A further study found that better diet quality at ages 1, 2 and 3 years was associated with higher academic scores at ages 10 and 12 years. Examination of nutritional intake at 14 years of age found that a better dietary pattern was associated with higher academic performance. The detailed longitudinal data collected in the Raine Study allowed for adjustment for multiple covariates and confounders. Data linkage reduces the burden on cohort participants by providing additional information without the need to contact participants. It can give information on participants who have been lost to follow-up; provide or complement missing data; give the opportunity for validation studies comparing recall of participants with administrative records; increase the population sample of studies by adding control participants from the general population; and allow for the adjustment of multiple covariates and confounders. The Raine Study dataset is extensive and detailed, and can be

The Alberta Pregnancy Outcomes and Nutrition (APrON) cohort study: rationale and methods.

Science.gov (United States)

Kaplan, Bonnie J; Giesbrecht, Gerald F; Leung, Brenda M Y; Field, Catherine J; Dewey, Deborah; Bell, Rhonda C; Manca, Donna P; O'Beirne, Maeve; Johnston, David W; Pop, Victor J; Singhal, Nalini; Gagnon, Lisa; Bernier, Francois P; Eliasziw, Misha; McCargar, Linda J; Kooistra, Libbe; Farmer, Anna; Cantell, Marja; Goonewardene, Laki; Casey, Linda M; Letourneau, Nicole; Martin, Jonathan W

2014-01-01

The Alberta Pregnancy Outcomes and Nutrition (APrON) study is an ongoing prospective cohort study that recruits pregnant women early in pregnancy and, as of 2012, is following up their infants to 3 years of age. It has currently enrolled approximately 5000 Canadians (2000 pregnant women, their offspring and many of their partners). The primary aims of the APrON study were to determine the relationships between maternal nutrient intake and status, before, during and after gestation, and (1) maternal mood; (2) birth and obstetric outcomes; and (3) infant neurodevelopment. We have collected comprehensive maternal nutrition, anthropometric, biological and mental health data at multiple points in the pregnancy and the post-partum period, as well as obstetrical, birth, health and neurodevelopmental outcomes of these pregnancies. The study continues to follow the infants through to 36 months of age. The current report describes the study design and methods, and findings of some pilot work. The APrON study is a significant resource with opportunities for collaboration. © 2012 John Wiley & Sons Ltd.

Dietary Fat Intake and Fecundability in 2 Preconception Cohort Studies

DEFF Research Database (Denmark)

Wise, Lauren A; Wesselink, Amelia K; Tucker, Katherine L

2018-01-01

American preconception cohort studies. Women who were attempting to become pregnant completed a validated food frequency questionnaire at baseline. Pregnancy status was updated bimonthly for 12 months or until pregnancy. Fecundability ratios (FR) and 95% confidence intervals were estimated using...

Maternal use of fertility drugs and risk of cancer in children--a nationwide population-based cohort study in Denmark

DEFF Research Database (Denmark)

Hargreave, Marie; Jensen, Allan; Nielsen, Thor Schütt Svane

2015-01-01

Large population-based studies are needed to examine the effect of maternal use of fertility drugs on the risk of cancer in children, while taking into account the effect of the underlying infertility. A cohort of 123,322 children born in Denmark between 1964 and 2006 to 68,255 women who had been...... evaluated for infertility was established. We used a case-cohort design and calculated hazard ratios (HRs) for cancer in childhood (0-19 years) and in young adulthood (20-29 years) associated with maternal use of six groups of fertility drugs (clomiphene, gonadotropins [i.e., human menopausal gonadotropins...... and follicle-stimulating hormone], gonadotropin-releasing hormone analogs, human chorionic gonadotropins, progesterone and other fertility drugs). We found no statistically significant association between maternal use of fertility drugs and risk for overall cancer in childhood or young adulthood. However...

Hyperthyroidism and thyroid cancer risk: a population-based cohort study.

Science.gov (United States)

Yeh, N-C; Chou, C-W; Weng, S-F; Yang, C-Y; Yen, F-C; Lee, S-Y; Wang, J-J; Tien, K-J

2013-07-01

Thyroid hormones regulate the rate of metabolism and affect the differentiation and growth of many tissues in the body. We investigated the association between hyperthyroidism and cancer risk in Taiwan. A random sample of 1 000 000 individuals from Taiwan's National Health Insurance database was enrolled. We found 17 033 patients to have newly diagnosed hyperthyroidism between 2000 and 2005. These patients were recruited along with a match cohort of 34 066 patients without hyperthyroidism. Starting from index date, we followed up all patients for 4 years to identify those who developed cancer. During the 4-year follow-up study, cancer was diagnosed in 1.23% of patients with hyperthyroidism and 1.02% of the member of the comparison cohort. Regression analysis showed that patients with hyperthyroidism were at greater risk of cancer incidence, especially thyroid cancer, compared the comparison cohort (HR: 1.213; 95% CI: 1.022-1.440; phyperthyroidism remained at increased risk of cancer incidence and thyroid cancer (Adjusted HR: 1.206; 95% CI: 1.015-1.433 and 6.803; 95% CI: 3.584-12.91, respectively) (both phyperthyroidism, the greater the risk of thyroid cancer. This 4-year follow up study suggests that patients with hyperthyroidism are at increased risk of cancer, especially thyroid cancer. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

Knee disarticulation : Survival, wound healing and ambulation. A historic cohort study

NARCIS (Netherlands)

Ten Duis, K.; Bosmans, J. C.; Voesten, H. G. J.; Geertzen, J. H. B.; Dijkstra, P. U.

2009-01-01

The aim of this study was to analyze survival, wound healing and ambulation after knee disarticulation (KD). A historic cohort study using medical records and nursing home records was performed. Data included demographics, reason for amputation, concomitant diseases, survival, wound healing,

Risk of Nephrotic Syndrome following Enteroviral Infection in Children: A Nationwide Retrospective Cohort Study.

Science.gov (United States)

Lin, Jiun-Nong; Lin, Cheng-Li; Yang, Chi-Hui; Lin, Ming-Chia; Lai, Chung-Hsu; Lin, Hsi-Hsun; Kao, Chia-Hung

2016-01-01

Nephrotic syndrome is a common chronic illness encountered during childhood. Infections have been identified as a cause of nephrotic syndrome. The aim of this study was to evaluate the association between enteroviral infection and nephrotic syndrome. A nationwide retrospective cohort study was conducted by analyzing data from the National Health Insurance Research Database in Taiwan. Children aged children were randomly selected as the comparison cohort. The primary endpoint was the occurrence of nephrotic syndrome. This study included 280,087 enterovirus-infected children and 280,085 non-enterovirus-infected children. The mean age of the enterovirus-infected children was 2.38 years, and 53.7% of these children were boys. The overall incidence densities of nephrotic syndrome for enterovirus- and non-enterovirus-infected children were 2.65 and 2.21 per 10,000 person-years, respectively. The enterovirus-infected cohort had a higher cumulative incidence of nephrotic syndrome than did the non-enterovirus-infected cohort (log-rank test, p = 0.01). Multivariable analyses revealed that children with enteroviral infection were significantly associated with an increased risk of nephrotic syndrome compared with those without enteroviral infection (adjusted hazard ratio, 1.20; 95% confidence interval, 1.04-1.39; p = 0.01), particularly in children infected with coxsackievirus. Subgroup analyses revealed that enterovirus-infected girls, children of blue-collar workers, and children without allergies had a higher risk of nephrotic syndrome than did children in the non-enterovirus-infected cohort. This study revealed a significant association between enteroviral infection and nephrotic syndrome. Additional studies elucidating the role and pathogenesis of enterovirus in nephrotic syndrome are warranted.