title: Problem of using cases with genetic anomalies as a reference group in case-control studies on drug use and birth defects.
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Martínez-Frías
authors.forename: Elvira
authors.initials: E
authors.lastname: Rodríguez-Pinilla
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000235:genetics*; D016022:Case-Control Studies; D000013:Congenital Abnormalities / Q000235:genetics*; D006801:Humans; D009154:Mutation