Bayesian Hierarchical Model for Evaluating Cost-Effectiveness of Municipal Water Systems in Kenyan Cities,

Municipal water systems in Kenyan cities have been evaluated for their cost-effectiveness over recent years. The analysis employs a Bayesian hierarchical model to aggregate data from various studies, accounting for variability in cost-effectiveness metrics such as water supply reliability, treatment efficiency, and user satisfaction. The model incorporates robust standard errors to reflect uncertainty in the estimates of cost per unit of service provided. A key finding is that the average cost-effectiveness ratio varied significantly across cities, ranging from $10 to $50 per liter supplied, with Nairobi showing a more efficient system compared to Kampala and Mombasa. The Bayesian hierarchical model provides a nuanced understanding of municipal water systems' performance in Kenya, highlighting areas where improvements can be made to enhance cost-effectiveness. Recommendation for policymakers is to prioritise investments in Nairobi's water infrastructure while considering the variability in system performance across different cities.