The Win Ratio: What Is It?

• Activity Number: 75 - Clinical Trial Design-1
• Type: Contributed
• Date/Time: Sunday, July 29, 2018 : 4:00 PM to 5:50 PM
• Sponsor: Biopharmaceutical Section
• Author(s): Victoria Chang* and Gaohong Dong and Marc Vandemeulebroecke and Junshan Qiu and Roland Matsouaka and Di Li and David Hoaglin
• Companies: AbbVie and iStats Inc. and Novartis and US Food and Drug Administration and Duke University School of Medicine and Bristol-Myers Squibb Co. and University of Massachusetts Medical School
• Keywords: Win ratio; Composite endpoint; Prioritized outcomes; Stratified win ratio; Prioritized pairwise comparison; Worst-event composite

Abstract

A composite endpoint combining multiple outcomes as a single endpoint is frequently used as the primary endpoint for clinical trials. Conventionally time-to-first-event of the multiple outcomes is analyzed. The win ratio (Pocock et al., 2012) considering the clinical importance order of the outcomes is appealing. This method is carried out by comparing each patient in the Treatment group with every patient in the Control group to determine the winner/loser/tie within each pair. Each pair comparison starts with the most important outcome (e.g. death), with lower priority outcomes (e.g. graft loss in transplant trials) being used only if higher priority outcomes are missing or result in a tie. The win ratio is the ratio of the numbers of wins in the two treatment groups. It has been applied to data analysis and study design of clinical trials. However, for clinical trialists, the interpretation of the win ratio seems to require clarification. In this talk, we will first demonstrate what the win ratio really is, then introduce the generalized solution to the win ratio (Dong et al., 2016) and the stratified win ratio (Dong et al., 2017) using clinical trial applications.