Introduction
Subject safety and scientific validity require sites to avoid enrolling subjects who are taking “concomitant” medications (“conmeds”) and to properly handle enrolled subjects who start taking these medications. In a typical study, the coordinator screens potential subjects against the list of prohibited (i.e., restricted) medications in the protocol’s eligibility requirements. Later, if the person enrolls in the study, the coordinator checks for problems with any new medications. The investigator presumably reviews the coordinators work. The site monitor verifies that the coordinator did not miss any prohibited medications. After data lock, the scientists and biostatisticians review the data to catch any remaining problems. This system relies on three troubling assumptions…
