Non-monetary numeraires: Varying the payment vehicle in a choice experiment for health interventions in Uganda

Schistosomiasis is a serious health problem in many parts of Africa which is linked to poor water quality and limited sanitation resources. We administered a discrete choice experiment on water access and health education in rural Uganda, focussing on interventions designed to reduce cases of the disease. Unlike previous studies, we included a payment vehicle of both labour hours supplied per week and money paid per month within each choice set. We were thus able to elicit both willingness to pay and willingness to work for alternative interventions. Respondents exhibit high demand for new water sources. From the random parameter model, only households with knowledge about water-borne parasites are price sensitive and exhibit willingness to pay values. Through a latent class model specification, higher income respondents exhibit higher willingness to pay values for all programme attributes; however, lower income participants have higher willingness to work values for certain new water sources. We found a shadow wage rate of labour that is between 15 and 55% of the market wage rate.