The incorporation of income and leisure in health state valuations when the measure is silent: an empirical inquiry into the sound of silence.

OBJECTIVE: The objective of the present study is to evaluate whether people 1) expect income and leisure to be affected by certain health states, 2) include the effects of ill-health on income and leisure in health state valuations when the measure is silent on both, and 3) what effect this has on these valuations. DATA AND METHODS: A convenience sample of 75 individuals from the general public rated 3 different health states on a visual analogue scale without instruction on the incorporation of income and leisure. Different subgroups were created on the basis of expecting income and leisure to be affected and the indicated incorporation of these effects. Comparative and multivariate analyses were used to analyze the data.
RESULTS: The results show that most respondents (69%) did not consider income effects, whereas 61% did consider the effects on leisure. The expected influence of health states on income and leisure differed substantially between respondents. Only the incorporation of leisure proved to be influential in health state valuations.
CONCLUSIONS: Health state valuation methods that are silent and noninformative regarding leisure and income lead to interrespondent differences regarding how they expect leisure and income to be affected and regarding the inclusion of these effects. This may be especially problematic for leisure if productivity costs are captured at the cost side of the cost-effectiveness ratio.