Starting from a finite or countable set of states of health, and assuming the existence of an objective transitive preference relation on that set, we propose a way of performing interpersonal comparisons of states of health. In so doing, we first consider the population divided into types, and consider that two individuals of a different type have a comparable state of health whenever they sit at the same centile of their respective type. A way of comparing and evaluating states of health for different groups is then proposed and rationalized. This can be viewed as both an alternative and an extension of the traditional QALY approach.