title: Sampling issues for natural history studies including intravenous drug abusers.
authors.affiliation: AIDS Outreach Intervention Program, School of Public Health, University of Illinois, Chicago 60612.
authors.forename: W W
authors.initials: WW
authors.lastname: Wiebel
mesh_terms: D015658:HIV Infections / Q000453:epidemiology*; D006801:Humans; D012107:Research Design; D012494:Sampling Studies; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*; D014481:United States