Time-dependent study entries and exposures in medical research: sources of different and avoidable types of bias

Martin Wolkewitz, Arthur Allignol, Stephan Harbarth, Giulia De Angelis, Martin Schumacher & Jan Beyersmann
Background: Survival bias is a common concern in medical applications of survival analysis since wrong results may directly impact patient care. We discuss two avoidable types of bias which might occur in presence of a time-dependent study entry ('length bias') or a time-dependent exposure[for full text, please go to the a.m. URL]