Caveat medicus : it's time to re-think stratification, you may not be helping

Abstract

Background The focus of the present Letter is on the large and seemingly fertile body of work captured under the umbrella of ‘patient stratification’. Objectives I identify and explain a fundamental methodological flaw underlying the manner in which the development of an increasingly large number of new stratification strategies is approached. Design I show an inherent conflict between the assumptions made, and the very purpose of stratification and its application in practice. Methods I analyse the methodological underpinnings of stratification as presently done and draw parallels with conceptually similarly flawed precedents which are now widely recognized. Results The highlighted flaw is shown to undermine the overarching ultimate goal of improved patient outcomes by undue fixation on an ill-founded proxy. Conclusion I issue a call for a re-think of the problem and the processes leading to the adoption of new stratification strategies in the clinic.