Two versions of the time-tradeoff (TTO) method were compared. In the personal TTO version, 31 prostate cancer patients decided whether they personally would give up some longevity to have perfect health rather than a longer life in a state of poor health associated with prostate cancer. In the impersonal version, 28 patients compared two hypothetical friends, one of whom has perfect health but will live less time than the other who is in poor health, and decided which person they would rather be. All patients evaluated three hypothetical health states. The two TTO methods were assessed by examining 1) how well they distinguished three health states of varying degrees of dysfunction and 2) patients' willingness to trade time for quality of life. Patients using the impersonal TTO version were more likely than those using the personal version to order the three health states appropriately (68% vs 16%, p < 0.0001) and were more willing to trade off length of life for quality of life (p < 0.05).