Sample size re-estimation in an on-going NIH-sponsored clinical trial: the secondary prevention of small subcortical strokes experience. Contemp Clin Trials 2012;33:1088–1093.Leslie A. McClure, Jeff M. Szychow
sample size re-estimationsurvival dataerror ratesextrapolationThis paper presents practical approaches to the problem of sample size re-estimation in the case of clinical trials with survival data when proportional hazards can be assumed. When data are readily available at the time of the review, on...
Information before unblinding regarding the success of confirmatory clinical trials is highly uncertain. Current techniques using point estimates of auxiliary parameters for estimating expected blinded sample size: (i) fail to describe the range of likely sample sizes obtained after the anticipated data ...
The estimation step in the E + M approach may be able to generate a flatter tail probability curve, and this may increase the significance level of a test and finally lead to a possible power gain. Shan et al. [89] were the first to extend the E + M approach for the sample size ...
The sample size estimation is an extremely important part in the clinical trials of medical devices, which is directly related to whether the research conclusion can reach the expectations. Although mathematical statistics indicate that the larger the sample size, the closer...
These include methods such as Bayesian Assurance, where the effect size is parameterized in the form of a distribution of values as opposed to a single value, and unblinded sample size re-estimation, where the effect size can be updated midway through a study based on data collected up to ...
记录方案违反( Protocol deviation) 样本量大小的确定( sample size estimation) 稽查( Au…baike.baidu.com|基于3个网页 2. 样本含量估计 样本量计... ... ) Sampling size 统计样本量 ) Sample Size Estimation 样本含量估计 ) Sample Size Re-estimation 样本量再估计 ... www.dictall.com|基于2个网页 ...
Multi-centre randomized controlled clinical trials play an important role in modern evidence-based medicine. Advantages of collecting data from more than one site are numerous, including accelerated recruitment and increased generalisability of results.
Sample size re-estimation: a review and recommendations. Drug Information Journal, 2006; 40(4):475-484 Focus Late-stage (Phase III, IV) sample size re-estimation Frequentist methods Control of Type I error Potential for bias is critical in these ‘confirmatory’ trials ...
Sary The need for sample size calculations is briefly reviewed: many of the arguments against small trials are already wel known, and we only cursorily repeat them in passing. Problems that arise in the estimation of sample size are then sed, with particular to survival studies. However, most...