Document 2323
 DOCN  M94A2323
 TI    Backcalculation using dates of HIV antibody tests.
 DT    9412
 AU    Dietz K; Dept. of Med. Biometry, Tuebingen, Germany.
 SO    Int Conf AIDS. 1994 Aug 7-12;10(1):330 (abstract no. PC0255). Unique
       Identifier : AIDSLINE ICA10/94370252
 AB    OBJECTIVE: To estimate past incidence of HIV infection, of HIV antibody
       testing and of treatment on the basis of data on AIDS incidence together
       with dates of HIV antibody tests for those cases for whom a test was
       performed before AIDS diagnosis and to estimate current HIV prevalence
       with and without an HIV diagnosis. METHODS: The backcalculation method
       is based on a Markov model for the incubation time distribution which
       describes as well the transitions from infection to AIDS as through the
       states not yet tested, tested, not yet treated and tested and treated.
       The method is illustrated using data on AIDS cases reported to the
       German Federal Office of Health in Berlin. RESULTS: The peak HIV
       incidence for homosexuals, IV drug users and heterosexual contacts
       occurred in 1983, 1984 and 1987, respectively. The proportion of the
       overall prevalence without a test is about one third. The absolute total
       prevalence at the end of 1993 is stimated between 30,000 and 40,000.
       DISCUSSION AND CONCLUSION: (i) The method may be applied in other
       countries where dates of tests are collected on a routine basis. (ii)
       The estimates of the prevalence of treated HIV positives agree well with
       the results of surveys among samples of medical practitioners.
 DE    Acquired Immunodeficiency Syndrome/*EPIDEMIOLOGY/TRANSMISSION  AIDS
       Serodiagnosis/*STATISTICS & NUMER DATA  Female  Germany/EPIDEMIOLOGY
       Homosexuality/STATISTICS & NUMER DATA  Human  HIV
       Infections/*EPIDEMIOLOGY/TRANSMISSION  HIV Seroprevalence/TRENDS  Male
       Population Surveillance  Substance Abuse,
       Intravenous/COMPLICATIONS/EPIDEMIOLOGY  MEETING ABSTRACT

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).