       Document 1255
 DOCN  M9591255
 TI    A nonparametric analysis of the transmission rate of human
       immunodeficiency virus from mother to infant.
 DT    9509
 AU    Tsai WY; Goedert JJ; Orazem J; Landesman SH; Rubinstein A; Willoughby A;
       Gail MH; Division of Biostatistics, Columbia University, New York, New;
       York 10032.
 SO    Biometrics. 1994 Dec;50(4):1015-28. Unique Identifier : AIDSLINE
       MED/95306581
 AB    Infants born to mothers who are infected with the human immunodeficiency
       virus (HIV) may or may not become infected by perinatal transmission.
       Unfortunately, passively transferred maternal antibodies make it hard to
       determine the infant's infection status from HIV antibody testing,
       because shortly after birth it is not possible to distinguish passively
       transferred maternal antibodies from antibodies produced by an infected
       infant. Usually, the infection status is unobservable for each infant,
       unless the infant reaches the age of 15 months or develops an
       HIV-related disease such as the acquired immunodeficiency syndrome
       (AIDS). Traditionally, statistical analyses of the perinatal
       transmission rate of HIV are based on infants who had been born at least
       15 months before the date of analysis. Such analyses can be both
       inefficient and biased. In this note, we define a mixture model
       underlying the onset time of AIDS and then obtain the nonparametric
       maximum likelihood estimators of the HIV transmission rate and of the
       distribution function of AIDS onset time for infected infants.
       Nonparametric tests are also derived for detecting differences in HIV
       transmission rates among different groups of infants. Finally, the
       methods are applied to the Mothers and Infants Cohort Study in New York
       City. The transmission rate of HIV from infected mothers to their
       infants was estimated to be 30.0% with 95% confidence interval (22.3%,
       39.1%).
 DE    Age of Onset  Bias (Epidemiology)  Biometry/METHODS  Comparative Study
       Disease Transmission, Vertical/*STATISTICS & NUMER DATA  Female
       Follow-Up Studies  Human  HIV Antibodies/BLOOD  HIV
       Infections/*TRANSMISSION  Infant  Infant, Newborn  Infant, Premature
       Mathematics  Pregnancy  Pregnancy Complications, Infectious/*VIROLOGY
       Probability  Support, U.S. Gov't, P.H.S.  Time Factors  JOURNAL ARTICLE

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

