Trying to estimate a monetary value for the QALY

In this paper we study the possibility of estimating a monetary value for the QALY. Using two different surveys of the Spanish population (n=900), we try to establish whether willingness to pay (WTP) is (almost) proportional to the health gains measured in QALYs. We also explore whether subjects’ responses are prone to any biases. We find that the monetary value of the QALY is higher the smaller the health gain, pointing to insensitivity in WTP. We also find two clear biases. One is the existence of sequencing effects. The other is the insensitivity of WTP to the duration of the period of payment. All these effects translate into a large variation in estimates of the monetary value of the QALY. We conclude that in order to be able to obtain consistent and stable estimates, we should try to understand better the causes of these problems with a view to developing ways of mitigating them.