The reliability and validity of willingness to pay surveys for reproductive health pricing decisions in developing countries

Abstract

This paper examines the reliability, theoretical and predictive validity of willingness to pay (WTP) surveys for setting prices for reproductive health services in developing countries. Four country applications were conducted; the surveys used similar elicitation methods (a series of three closed-ended questions to cover the range of target prices, followed by a single open ended question to elicit maximum WTP) and samples of current or potential users of family planning, gynecology, and prenatal care services. In all four applications, respondents were able to understand WTP questions and responded with high levels of internal consistency. Evidence supporting theoretical validity was also found in all surveys. Higher income and more highly motivated users had higher WTP than lower income and less motivated users. Predictive validity was assessed in one study. Services utilization predicted by a WTP survey was compared with actual post-price increase utilization. Adding WTP to information already possessed by program managers resulted in a threefold increase in ability to predict utilization change as a result of a price increase, and in nearly half of cases predicted percent change in utilization was within 10% of observed change. WTP surveys when used for reproductive services price setting appear reliable and valid, and improve a program manager's ability to predict client responses to price changes.