Baseline selection on a collider: a ubiquitous mechanism occurring in both representative and selected cohort studies
Lorenzo Richiardi, Neil Pearce, Eva Pagano, Daniela Di Cuonzo, Daniela Zugna, Costanza Pizzi
J Epidemiol Community Health May 2019, 73 (5) 475-480; DOI: 10.1136/jech-2018-211829