Clinical Trial Service Unit

About: Clinical Trial Service Unit is a based out in . It is known for research contribution in the topics: Population & Stroke. The organization has 428 authors who have published 1387 publications receiving 181920 citations.

The importance of reducing SFA to limit CHD.

Abstract: Jan I. Pedersen*, Philip T. James, Ingeborg A. Brouwer, Robert Clarke, Ibrahim Elmadfa, Martijn B. Katan, Penny M. Kris-Etherton, Daan Kromhout, Barrie M. Margetts, Ronald P. Mensink, Kaare R. Norum, Mike Rayner and Matti Uusitupa Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, POB 1046 Blindern, 0316 Oslo, Norway London School of Hygiene and Tropical Medicine, London, UK Department of Health Sciences, VU University, 1081 HV Amsterdam, The Netherlands Clinical Trial Service Unit, University of Oxford, Oxford, UK Institute of Nutritional Sciences, University of Vienna, 1090 Vienna, Austria Department of Nutritional Sciences, Penn State University, University Park, PA 16802, USA Division of Human Nutrition, Wageningen University, 6700 EV, Wageningen, The Netherlands Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK Department Human Biology, School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands British Heart Foundation Health Promotion Research Group, Department of Public Health, University of Oxford, Oxford, UK Institute of Public Health and Clinical Nutrition, Clinical Nutrition, Kuopio Campus, University of Eastern Finland, Kuopio, Finland

Post-trial follow-up methodology in large randomised controlled trials: a systematic review

Abstract: Randomised controlled clinical trials typically have a relatively brief in-trial follow-up period which can underestimate safety signals and fail to detect long-term hazards, which may take years to appear. Extended follow-up after the scheduled closure of the trial allows detection of both persistent or enhanced beneficial effects following cessation of study treatment (i.e. a legacy effect) and the emergence of possible adverse effects (e.g. development of cancer). A systematic review was conducted following PRISMA guidelines to qualitatively compare post-trial follow-up methods used in large randomised controlled trials. Five bibliographic databases, including Medline and the Cochrane Library, and one trial registry were searched. All large randomised controlled trials (more than 1000 adult participants) published from March 2006 to April 2017 were evaluated. Two reviewers screened and extracted data attaining > 95% concordance of papers checked. Assessment of bias in the trials was evaluated using the Cochrane Risk of Bias tool. Fifty-seven thousand three hundred and fifty-two papers were identified and 65 trials which had post-trial follow-up (PTFU) were included in the analysis. The majority of trials used more than one type of follow-up. There was no evidence of an association between the retention rates of participants in the PTFU period and the type of follow-up used. Costs of PTFU varied widely with data linkage being the most economical. It was not possible to assess associations between risk of bias during the in-trial period and proportions lost to follow-up during the PTFU period. Data captured during the post-trial follow-up period can add scientific value to a trial. However, there are logistical and financial barriers to overcome. Where available, data linkage via electronic registries and records is a cost-effective method which can provide data on a range of endpoints. Not applicable for PROSPERO registration.