The influence of subjective expectations about length and quality of life on time trade-off answers

When answering TTO questions respondents sometimes have to imagine being in a certain health state during their remaining lifespan, often based on objective life tables. Respondents however may have subjective expectations about length and quality of life that differ from the objective ones. If respondents do not fully from own expectations, TTO scores may be biased. In this note, we indicate how subjective expectations could influence TTO scores and present some empirical findings suggesting that they do. Our results indicate that subjective expectations may serve as unobserved reference points and as such influence TTO responses. Copyright © 2004 John Wiley & Sons, Ltd.