Pinto, J.L., C. Herrero and J.M. Abellán
The Oxford Handbook of Well-Being and Public Policy – Chapter 6, Oxford U. Press (2016)
Abstract: QALYs are one of the most influential output measures used by public agencies making decisions in the health area. In this chapter we develop the use of the QALY model in Health Decision Making as well as the most popular alternatives. We also analyse the conditions on preferences for them to be represented by the traditional QALY model both at the individual and at the collective decision making level, concluding that they are difficult to be fulfilled. We may then ask why is such a disputed model so widely used? Several explanations are possible. One is that all models are limited. Another explanation is that the linear QALY model has a long tradition in health policy. It was developed and proposed without an explicit appeal to preferences but it was found to be useful. A final explanation is that the model is simple—simple to explain, simple to apply, simple to use— and it is not clear how inaccurate the model is. In summary, one hypothesis is that the popularity of QALYs is not related to the theoretical and empirical strength of the model, but to its simplicity coupled with the fact that it has reasonable ordinal properties. Precisely because it is simple, it is easy to criticize but it is difficult to come up with better and more practical alternatives.