       Document 0309
 DOCN  M9550309
 TI    Incorporating HIV test data into forecasts of the AIDS epidemic in
       Scotland.
 DT    9505
 AU    Raab GM; Fielding KL; Allardice G; MRC Biostatistics Initiative for HIV
       and AIDS in Scotland,; Edinburgh, U.K.
 SO    Stat Med. 1994 Oct 15-30;13(19-20):2009-20. Unique Identifier : AIDSLINE
       MED/95148998
 AB    For AIDS cases in Scotland the date of HIV antibody positive diagnosis
       (HIV test date) is recorded on the AIDS case reports. Data are also
       available on the total numbers of individuals with HIV positive test
       reports in Scottish laboratories in each year since testing became
       available. These data are incorporated into a model of the HIV epidemic
       described in terms of testing rates by calendar year. The HIV infection
       curve is modelled as a step function, and the testing rates are allowed
       to differ between steps. Results are presented for intravenous drug
       users (IDUs) and for homosexual/bisexual men. The estimated rates of
       testing for the IDUs (estimates from 19 per cent to 44 per cent per
       year) are considerably higher than those for homosexual/bisexual men
       (estimates of 10 per cent to 17 per cent per year). Data on the year of
       testing for AIDS diagnoses gave relatively little improvement in
       estimates of the HIV infection curve. However, when this information is
       combined with data on the total number of HIV positive diagnoses per
       year, there is a dramatic improvement in the estimate of the HIV
       infection curve. This is particularly marked for infections in the most
       recent period and for the estimates of cumulative infections up to the
       present. However, these improvements are gained at the cost of
       assumptions of similar testing rates applying to all sections of the HIV
       infected populations, which will be difficult to check in practice. This
       suggests that these methods should not be used in isolation but in
       combination with other evidence about the spread of HIV infection in a
       population.
 DE    Acquired Immunodeficiency Syndrome/*EPIDEMIOLOGY  Bayes Theorem
       Forecasting  Homosexuality, Male  Human  HIV
       Infections/DIAGNOSIS/*EPIDEMIOLOGY/TRANSMISSION  Immunoassay/STATISTICS
       & NUMER DATA  Likelihood Functions  Male  *Models, Biological
       Prevalence  Retrospective Studies  Risk Factors  Scotland/EPIDEMIOLOGY
       Substance Abuse, Intravenous  Support, Non-U.S. Gov't  Time Factors
       JOURNAL ARTICLE

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

