A cost-benefit analysis of preventive schistosomiasis interventions in Kenya

The objectives of this paper are fourfold: first, to develop a model for a cost benefit analysis (CBA) to appraise various preventive schistosomiasis interventions; second, to identify the relevant types of data needed for such a model; third, to use the model to inform choices about optimal prevention strategies; and fourthly, to discuss the utility of this form of decision analysis to policy-makers. The following data were used: expected costs of each option over the 15 year project life; willingness-to-pay value for health states (outcomes); probabilities of health states with and without various interventions; 15 year population forecasts; discount factors for each year; and a standard conversion factor. All the interventions examined had a positive net present value, with the drip mollusciciding option dominating the other options. The study also highlighted the fact that there is as need for collaboration between tropical disease epidemiologists and health economists in the design and execution of randomized controlled trails to obtain the probabilistic effectiveness data needed in such decision analyzes.