Journal•ISSN: 1740-7745
Clinical Trials
SAGE Publishing
About: Clinical Trials is an academic journal published by SAGE Publishing. The journal publishes majorly in the area(s): Clinical trial & Randomized controlled trial. It has an ISSN identifier of 1740-7745. Over the lifetime, 1764 publications have been published receiving 37079 citations.
Papers published on a yearly basis
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TL;DR: Although IPD meta-analyses have many advantages in assessing the effects of health care, there are several aspects that could be further developed to make fuller use of the potential of these time-consuming projects.
Abstract: Background Meta-analyses based on individual patient data (IPD) are regarded as the gold standard for systematic reviews. However, the methods used for analysing and presenting results from IPD met...
532 citations
TL;DR: A test to explore biases stemming from the pursuit of nominal statistical significance was developed and demonstrated a clear or possible excess of significant studies in 6 of 8 large meta-analyses and in the wide domain of neuroleptic treatments.
Abstract: Background The published clinical research literature may be distorted by the pursuit of statistically significant results.Purpose We aimed to develop a test to explore biases stemming from the pur...
529 citations
TL;DR: It is shown that missing outcome data are a common problem in randomized controlled trials, and are often inadequately handled in the statistical analysis in the top tier medical journals.
Abstract: Background Randomized controlled trials almost always have some individuals with missing outcomes. Inadequate handling of these missing data in the analysis can cause substantial bias in the treatment effect estimates. We examine how missing outcome data are handled in randomized controlled trials in order to assess whether adequate steps have been taken to reduce nonresponse bias and to identify ways to improve procedures for missing data.Methods We reviewed all randomized trials published between July and December 2001 in BMJ, JAMA, Lancet and New England Journal of Medicine, excluding trials in which the primary outcome was described as a time-to-event. We focused on trial designs, how missing outcome data were described and the statistical methods used to deal with the missing outcome data, including sensitivity analyses.Results We identified 71 trials of which 63 (89%) reported having partly missing outcome data: 13 trials had more than 20% of patients with missing outcomes. In 26 trials that measure...
479 citations
TL;DR: The Systolic Blood Pressure Intervention Trial will provide important information on the risks and benefits of intensive blood pressure treatment targets in a diverse sample of high-risk participants, including those with prior cardiovascular disease, chronic kidney disease, and those aged ≥75 years.
Abstract: Background:High blood pressure is an important public health concern because it is highly prevalent and a risk factor for adverse health outcomes, including coronary heart disease, stroke, decompensated heart failure, chronic kidney disease, and decline in cognitive function. Observational studies show a progressive increase in risk associated with blood pressure above 115/75 mm Hg. Prior research has shown that reducing elevated systolic blood pressure lowers the risk of subsequent clinical complications from cardiovascular disease. However, the optimal systolic blood pressure to reduce blood pressure–related adverse outcomes is unclear, and the benefit of treating to a level of systolic blood pressure well below 140 mm Hg has not been proven in a large, definitive clinical trial.Purpose:To describe the design considerations of the Systolic Blood Pressure Intervention Trial (SPRINT) and the baseline characteristics of trial participants.Methods:The Systolic Blood Pressure Intervention Trial is a multicen...
417 citations
TL;DR: It is recommended that all randomized clinical trials with substantial lack of adherence or loss to follow-up are analyzed using different methods, including an intention-to-treat analysis to estimate the effect of assigned treatment and ‘as treated’ and ’per protocol’ analyses to estimateThe effect of treatment after appropriate adjustment via inverse probability weighting or g-estimation.
Abstract: Background The intention-to-treat comparison is the primary, if not the only, analytic approach of many randomized clinical trials.Purpose To review the shortcomings of intention-to-treat analyses, and of ‘as treated’ and ‘per protocol’ analyses as commonly implemented, with an emphasis on problems that are especially relevant for comparative effectiveness research.Methods and Results In placebo-controlled randomized clinical trials, intention-to-treat analyses underestimate the treatment effect and are therefore nonconservative for both safety trials and noninferiority trials. In randomized clinical trials with an active comparator, intention-to-treat estimates can overestimate a treatment’s effect in the presence of differential adherence. In either case, there is no guarantee that an intention-to-treat analysis estimates the clinical effectiveness of treatment. Inverse probability weighting, g-estimation, and instrumental variable estimation can reduce the bias introduced by nonadherence and loss to fo...
355 citations