title: Personality differences of volunteer and nonvolunteer heroin and nonheroin drug users.
mesh_terms: D000328:Adult; D006556:Heroin Dependence / Q000534:rehabilitation*; D006801:Humans; D008950:MMPI; D008297:Male; D010342:Patient Acceptance of Health Care; D010551:Personality; D012917:Social Adjustment; D019966:Substance-Related Disorders / Q000534:rehabilitation*