title: Statistical evaluation of surrogate markers: validity, efficiency, and sensitivity.
abstract: Identification of surrogate markers for a marketed drug is important in monitoring the efficacy or safety after a patient uses the drug. In this article, we clarify the statistical definitions of the surrogate endpoint and surrogate marker and introduce the concept of the validity and efficiency of a surrogate marker. We also review some existing methods and suggest the proportion of information gain is appropriate to be used to evaluate the validity of a surrogate marker.
authors.affiliation: Department of Biometrics, Lilly Corporate Center, Eli Lilly and Company, Indianapolis, IN, USA.
authors.forename: Yongming
authors.initials: Y
authors.lastname: Qu
mesh_terms: D015415:Biomarkers; D002986:Clinical Trials as Topic / Q000379:methods*; D003627:Data Interpretation, Statistical; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers