A systematic review of methods for specifying the target difference in randomised controlled trials (delta review)
نویسندگان
چکیده
Background Determining the sample size is a vital aspect of randomised control trial design; typically a (target) difference is specified. This provides reassurance that the study will be informative; i.e. should such a difference exist, it is likely to be detected with the required statistical precision. From both a scientific and ethical standpoint, selecting an appropriate target difference is of crucial importance; too large or small a study is arguable unethical, wasteful and potentially misleading. While a variety of methods have been proposed to specify a target difference, their relative merits are unclear.
منابع مشابه
Methods for Specifying the Target Difference in a Randomised Controlled Trial: The Difference ELicitation in TriAls (DELTA) Systematic Review
BACKGROUND Randomised controlled trials (RCTs) are widely accepted as the preferred study design for evaluating healthcare interventions. When the sample size is determined, a (target) difference is typically specified that the RCT is designed to detect. This provides reassurance that the study will be informative, i.e., should such a difference exist, it is likely to be detected with the requi...
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