P1-S6.07 Ecological analysis of the factors influencing changes in HIV prevalence over time among FSW following a targeted intervention

Background Avahan is a large scale intervention that targets high-risk groups, including female sex workers (FSW), in many epidemiologically heterogeneous districts in southern India. Changes in HIV prevalence post intervention may depend on setting and intervention characteristics. We conducted an ecological analysis to identify which factors were associated with greater changes in FSW HIV prevalence after Avahan start in 2004. Methods All variables were derived from two serial rounds (R1, R2) of cross-sectional FSW surveys, conducted ∼3–4 years apart, from 24 districts of 4 Southern Indian states. We examined the association between the difference in FSW HIV prevalence between rounds (R2−R1)(D.FSW HIV) and different classes of factors (Abstract P1-S6.07 table 1). Intervention factors included differences between rounds in consistent condom use (CCU) with occasional clients, difference in STI prevalence, or fraction of FSW in contact with the intervention at R1, and others (see Abstract P1-S6.07 table 1). Baseline contextual factors included FSW HIV or STI prevalence, fraction of FSW ever asked for anal intercourse (AI), weekly client number per FSW etc at R1, estimates of CCU in 1998, and increase in CCU before R1. Design factors (date of R1, time between R2−R1, differences in response rate between R2 and R1), and differences in contextual factors between rounds as listed Abstract P1-S6.07 table 1 were also explored. Pearson correlations, univariate and multiple linear regression analysis were performed. Abstract P1-S6.07 Table 1 Results of univariate analysis between the difference in FSW HIV prevalence (R2-R1) and different independent variables for each class of factors Types of independent variables N Coefficient of correlation (r) (if pv