title: Three types of extreme drug users identified by a replicated cluster analysis.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013029:Space-Time Clustering; D019966:Substance-Related Disorders / Q000175:diagnosis*