Measuring health preferences for use in cost-utility and cost-benefit analyses of interventions in children: theoretical and methodological considerations.

Valuing the health of children for cost-utility or cost-benefit analysis poses a number of additional challenges when compared with valuing adult health. Some of these challenges relate to the inability of young children to value changes in health directly and the potential biases associated with using proxy respondents. Other challenges arise from children not being able to perform as independent economic actors, but dependent on others for care and decision making. In addition, illness in children may affect parent/caregiver quality of life, further complicating the measurement of value associated with a change in a child's health status. We review the most common approaches (QALYs and willingness-to-pay values) for valuing health in economic evaluations and consider the methodological and practical issues associated with measuring child health using each framework. Recommendations for advancing the field of valuing child health for economic evaluations will vary by age; a 'one size fits all' approach does not readily fit. Although limitations exist for all of the methods considered for valuing child health, the currently recommended approach for infants and preschoolers is direct valuation by a proxy respondent. For school-age children and adolescents, existing multi-attribute instruments can be applied in some situations but direct valuation may be required for others. Future research should focus on minimising bias from proxy respondents, consideration of a family- or household-based approach to valuing health effects, and development of generic instruments with domains that are appropriate to children and that vary with age.