title: [Defining control groups in epidemiological studies--problems of documentation and evaluation (author's transl)].
mesh_terms: D004282:Documentation; D004341:Drug Evaluation / Q000379:methods*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D011247:Pregnancy; D013223:Statistics as Topic
vernacular_title: Dokumentations- und Auswertprobleme bei der Definition von Kontrollgruppen in epidemiologischen Studien