title: Toward a definition of the schizoid state: evidence from studies of twins and their families.
mesh_terms: D002605:Character; D004200:Diseases in Twins; D005260:Female; D005826:Genetics, Medical; D006801:Humans; D008297:Male; D009497:Neurotic Disorders / Q000235:genetics; D010554:Personality Disorders / Q000235:genetics; D012557:Schizoid Personality Disorder / Q000235:genetics; D012559:Schizophrenia / Q000145:classification / Q000235:genetics*; D012737:Sex Factors