Modelling the impact and cost-effectiveness of the HIV intervention programme amongst commercial sex workers in Ahmedabad, Gujarat, India.

BACKGROUND: Ahmedabad is an industrial city in Gujarat, India. In 2003, the HIV prevalence among commercial sex workers (CSWs) in Ahmedabad reached 13.0%. In response, the Jyoti Sangh HIV prevention programme for CSWs was initiated, which involves outreach, peer education, condom distribution, and free STD clinics. Two surveys were performed among CSWs in 1999 and 2003. This study estimates the cost-effectiveness of the Jyoti Sangh HIV prevention programme. METHODS: A dynamic mathematical model was used with survey and intervention-specific data from Ahmedabad to estimate the HIV impact of the Jyoti Sangh project for the 51 months between the two CSW surveys. Uncertainty analysis was used to obtain different model fits to the HIV/STI epidemiological data, producing a range for the HIV impact of the project. Financial and economic costs of the intervention were estimated from the providers perspective for the same time period. The cost per HIV-infection averted was estimated. RESULTS: Over 51 months, projections suggest that the intervention averted 624 and 5,131 HIV cases among the CSWs and their clients, respectively. This equates to a 54% and 51% decrease in the HIV infections that would have occurred among the CSWs and clients without the intervention. In the absence of intervention, the model predicts that the HIV prevalence amongst the CSWs in 2003 would have been 26%, almost twice that with the intervention. Cost per HIV infection averted, excluding and including peer educator economic costs, was USD 59 and USD 98 respectively. CONCLUSION: This study demonstrated that targeted CSW interventions in India can be cost-effective, and highlights the importance of replicating this effort in other similar settings.Published versio

Does scale matter? The costs of HIV-prevention interventions for commercial sex workers in India.

OBJECTIVE: To explore how the scale of a project affects both the total costs and average costs of HIV prevention in India. METHODS: Economic cost data and measures of scale (coverage and service volume indicators for number of cases of sexually transmitted infections (STIs) referred, number of STIs treated, condoms distributed and contacts made with target groups) were collected from 17 interventions run by nongovernmental organizations aimed at commercial sex workers in southern India. Nonparametric methods and regression analyses were used to look at the relationship between total costs, unit costs and scale. FINDINGS: Coverage varied from 250 to 2008 sex workers. Annual costs ranged from US$11 274 to US$ 52 793. The median cost per sex worker reached was US$19.21 (range = US$ 10.00-51.00). The scale variables explain more than 50% of the variation in unit costs for all of the unit cost measures except cost per contact. Total costs and unit costs have non-linear relationships to scale. CONCLUSION: Average costs vary with the scale of the project. Estimates of resource requirements based on a constant average cost could underestimate or overestimate total costs. The results highlight the importance of improving scale-specific cost information for planning

Does scale matter? The costs of HIV-prevention interventions for commercial sex workers in India

OBJECTIVE: To explore how the scale of a project affects both the total costs and average costs of HIV prevention in India. METHODS: Economic cost data and measures of scale (coverage and service volume indicators for number of cases of sexually transmitted infections (STIs) referred, number of STIs treated, condoms distributed and contacts made with target groups) were collected from 17 interventions run by nongovernmental organizations aimed at commercial sex workers in southern India. Nonparametric methods and regression analyses were used to look at the relationship between total costs, unit costs and scale. FINDINGS: Coverage varied from 250 to 2008 sex workers. Annual costs ranged from US$11 274 to US$ 52 793. The median cost per sex worker reached was US$19.21 (range = US$ 10.00-51.00). The scale variables explain more than 50% of the variation in unit costs for all of the unit cost measures except cost per contact. Total costs and unit costs have non-linear relationships to scale. CONCLUSION: Average costs vary with the scale of the project. Estimates of resource requirements based on a constant average cost could underestimate or overestimate total costs. The results highlight the importance of improving scale-specific cost information for planning