title: Sample size: how many participants are needed in a cohort study?
authors.affiliation: Institute for Medical and Biomedical Education, St George's, University of London, London, UK p.sedgwick@sgul.ac.uk.
authors.forename: Philip
authors.initials: P
authors.lastname: Sedgwick
mesh_terms: D015331:Cohort Studies; D061366:Numbers Needed To Treat; D018401:Sample Size