title: Strategies for enhancing existing studies of the natural history of HIV-1 infection among drug users.
authors.affiliation: Sylvester Comprehensive Cancer Center, University of Miami School of Medicine, FL 33136.
authors.forename: D D
authors.initials: DD
authors.lastname: Chitwood
authors.forename: M
authors.initials: M
authors.lastname: Comerford
authors.forename: E J
authors.initials: EJ
authors.lastname: Trapido
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D012107:Research Design; D015819:Substance Abuse, Intravenous / Q000150:complications*; D014481:United States