Pinkerton Steven David, Chesson Harrell Warren, Layde Peter Mark
Center for AIDS Prevention Research, Department of Psychiatry and Behavioral Medicine, Milwaukee, WI 53202, USA.
J Acquir Immune Defic Syndr. 2002 Sep 1;31(1):71-9. doi: 10.1097/00126334-200209010-00010.
Most sexually transmitted disease (STD)/HIV sexual risk reduction intervention trials are evaluated using behavioral outcomes as their main indicators of intervention effectiveness. How good are behavioral measures as surrogate markers for STD infection? Do the behavioral changes that are commonly assessed in risk reduction interventions accurately reflect changes in STD risk? We applied a mathematical model of STD/HIV transmission to empiric data from a large HIV prevention intervention to estimate pre- to postintervention changes in intervention participants' STD risk. We then used the coefficient of determination (R(2)) to assess the strength of association between changes in STD risk and changes in three behavioral measures: proportion of acts of intercourse for which condoms were used, number of sex partners, and number of acts of unprotected intercourse. The results indicate that change in the number of acts of unprotected intercourse is a superior marker of STD risk changes for less infectious STDs such as HIV, whereas change in the number of partners may be preferable for highly infectious STDs such as gonorrhea. Changes in the proportion of acts of intercourse for which condoms were used were not strongly correlated with changes in STD risk under most of the conditions examined in this analysis. The utility of different measures of sexual behavior change as markers for changes in STD risk and, hence, expected incidence, depends on the infectivity and prevalence of the target STD.
大多数性传播疾病（STD）/艾滋病病毒（HIV）性风险降低干预试验都是以行为结果作为干预效果的主要指标进行评估的。行为指标作为STD感染替代标志物的效果如何？降低风险干预中通常评估的行为变化是否准确反映了STD风险的变化？我们将STD/HIV传播的数学模型应用于一项大型HIV预防干预的实证数据，以估计干预参与者干预前后STD风险的变化。然后，我们使用决定系数（R²）来评估STD风险变化与三种行为指标变化之间的关联强度：使用避孕套的性交行为比例、性伴侣数量以及无保护性交行为的次数。结果表明，对于传染性较低的STD（如HIV），无保护性交行为次数的变化是STD风险变化的更佳标志物，而对于传染性较高的STD（如淋病），性伴侣数量的变化可能更合适。在本分析所考察的大多数情况下，使用避孕套的性交行为比例的变化与STD风险的变化没有很强的相关性。不同性行为变化指标作为STD风险变化及预期发病率变化标志物的效用，取决于目标STD的传染性和流行率。
