Abstract:

Since the beginning of the HIV epidemic billions of dollars have supported countless HIV prevention programs. Yet worldwide, between 4.3 and 6.4 million persons were infected with HIV in 2004. Furthermore, the epidemic is projected to continue to grow in the next decade, especially in Africa and Asia. In the absence of a cure or vaccine it is imperative that efforts to refine and increase the effectiveness of HIV interventions continue. Improved program evaluation is vital to these efforts.

Although the ultimate objective of HIV prevention programs is to reduce the transmission of HIV, their evaluation is generally limited to an assessment of sexual behavior change. Evaluations that extend beyond assessments of sexual behavior change to include assessments of averted potential infections are needed to assess the impact HIV interventions have on disease transmission.

This evaluation was conducted on data collected between 1994 and 1996 as part of a quasi-experimental community-based HIV prevention program targeting commercial sex workers employed in entertainment establishments in the Philippines. The Philippines HIV prevention program consisted of an individual-level intervention, a structural level intervention, an intervention that combined individual-level and structural-level elements and a standard care comparison group. In this evaluation, the effectiveness of the interventions in affecting sexual behavior change among commercial sex workers was assessed. A Bernoulli mathematical model was then utilized to estimate the number of averted potential HIV infections resulting from sexual behavior change among the targeted commercial sex workers. The cost per averted potential HIV infection was also determined.

The evaluation showed that compared with interventions based on individual-level factors or structural-level elements alone, the comprehensive HIV prevention approach that incorporated both individual-level and structural-level factors was more effective at achieving sustained behavior change and averting potential HIV infections in the establishment-based commercial sex worker population. The comprehensive HIV prevention approach was also found to be the most cost effective. The evaluation also showed that sexual behavior change though informative, provided an incomplete representation of intervention impact on disease transmission.

The findings of this evaluation have important implications for HIV prevention program planning and HIV program evaluation practice.