title: Statistical issues in the planning of prevention studies.
authors.affiliation: Harvard School of Public Health, Boston, Massachusetts.
authors.forename: M
authors.initials: M
authors.lastname: Zelen
mesh_terms: D002986:Clinical Trials as Topic; D006801:Humans; D008962:Models, Theoretical; D009369:Neoplasms / Q000453:epidemiology / Q000517:prevention & control*; D010349:Patient Compliance; D012107:Research Design