Katz M H, Hessol N A, Buchbinder S P, Mebane W R, O'Malley P, Lemp G F, Holmberg S D
AIDS Office, Department of Public Health, San Francisco, CA 94102-6033.
J Acquir Immune Defic Syndr (1988). 1993 Mar;6(3):295-7.
To assess the immediate impact of the proposed CD4-based expansion of the AIDS case definition, we determined two key proportions from a subsample of men from the San Francisco City Clinic Cohort (SFCCC). We then used Bayes theorem to project the number of persons fitting the proposed definition in the entire SFCCC and in the city of San Francisco. Among those men meeting the 1987 AIDS case definition, the proportion with a CD4 cell count < 200 cells (within 6 months of their AIDS diagnosis) is 0.70 (16 of 23). Among those with a CD4 count ever < 200 cells, the proportion with AIDS is 0.40 (29 of 73). Our estimates show that 446 persons in the SFCCC and 3,603 persons in San Francisco would fit only the expanded definition. Thus, the proposed definition would likely more than double the number of persons who could be diagnosed with AIDS. Bayes theorem offers a simple method for estimating the immediate impact of the proposed CD4-based expansion of the AIDS case definition.
为评估基于CD4细胞计数扩大艾滋病病例定义的直接影响，我们从旧金山城市诊所队列（SFCCC）的男性子样本中确定了两个关键比例。然后，我们使用贝叶斯定理来推算整个SFCCC以及旧金山市符合拟议定义的人数。在那些符合1987年艾滋病病例定义的男性中，CD4细胞计数<200个细胞（在其艾滋病诊断的6个月内）的比例为0.70（23人中的16人）。在那些CD4计数曾<200个细胞的人中，患艾滋病的比例为0.40（73人中的29人）。我们的估计表明，SFCCC中有446人，旧金山市有3603人仅符合扩大后的定义。因此，拟议的定义可能会使可被诊断为艾滋病的人数增加一倍以上。贝叶斯定理提供了一种简单的方法来估计基于CD4细胞计数扩大艾滋病病例定义的直接影响。
