Protocol for "A Methodological Review of Response Adaptive Randomisation Methods, Trials, and Statistical Resources"

Introduction: Adaptive designs (ADs) give clinical trials more flexibility, allowing controlled modification of trial aspects by utilising accumulating outcome data. One such modification is RAR which provides the opportunity to update how participants are allocated to treatments using some method that gives more weight to the most promising and beneficial treatments as indicated by interim data. However, the uptake of RAR remains disproportionately low in comparison to other ADs (such as group sequential designs). There is a need for guidance resources to help bridge the gap between statisticalmethodology and implementation in a useful way for applied researchers

Objectives:This methodological review will be split into three work packages (WPs). The objectives of WP 1, 2, and 3 are, respectively, to identify statistical literature on response adaptive randomisation (RAR) methods applicable in clinical trials research, identify clinical trials that have used RAR methods, and identify RAR statistical implementation resources.