Differential time preferences for money and quality of life.

backgroundThis study provides an empirical investigation into differential time preferences between money and quality of life. Thus far, time preference investigations in health have mostly involved life-years gained and lives saved. However, the quality-adjusted life-year, which is recommended by several bodies, is a multiplicative measure of life duration and quality of life. To our knowledge, our study is the first to follow this approach specifically for quality of life.

methodsA questionnaire was developed to elicit time preferences for quality of life and for money, and it was distributed to a representative sample of the Dutch population. We also investigated the impact of population characteristics, such as current health state, optimistic/pessimistic future views or gender, on time preferences.

resultsWe found that discount rates for both money and quality of life decrease with increasing time of delay, with rates of the former being consistently at least two times higher than those of the latter. Similar trends in time preferences were observed across the subgroups, with the exception of the relatively high education subgroup.

conclusionIn agreement with the results of other studies, our empirically derived discount rates are higher than the rates featured in national guidelines for health care economic assessment. Our empirical study adds to the evidence for differential discounting, both with regards to money and health, as well as in time.