On responder analyses in the framework of within subject comparisons - considerations and two case studies

A responder analysis is a common tool when clinical data are reported. In this paper, we extend the definition of responders to within subject comparisons and present a rigorous definition of the corresponding statistical functional. Via simulation studies, we get further insights under which conditions these analyses can even result in a higher power compared with an analysis based on the arithmetic mean. We report two case studies where these analyses contributed to a better understanding of the clinical data especially as some large observations were present that had a notable impact on the observed standard deviation.