title: Portability of therapeutic effects (letter commenting: J Clin Epidemiol. 2015;68(11):1251--1260.).
authors.affiliation: Ruhr-Universität Bochum, Department of Medical Statistics, Universitätsstraße 150, 44801 Bochum, Germany. Electronic address: Hans.J.Trampisch@rub.de.
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Trampisch