Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Including informal care in economic evaluations is increasingly advocated but problematic. We investigated three well‐known concerns regarding contingent valuation (CV): (1) the item non‐response of CV values, (2) the sensitivity of CV values to the individual circumstances of caring, and (3) the choice of valuation method by comparing willingness‐to‐pay (WTP) and willingness‐to‐accept (WTA) values for a hypothetical marginal change in hours of informal care currently provided. The study sample consisted of 1453 caregivers and 787 care recipients. Of the caregivers, 603 caregivers (41.5%) provided both WTP and WTA values, 983 (67.7%) provided at least one. Determinants of non‐response were dependent on the valuation method; primary determinants were education and satisfaction with amount of informal care provided. Caregivers' mean WTP (WTA) for reducing (increasing) informal care by 1 h was €9.13 (10.52). Care recipients' mean WTA (WTP) for reducing (increasing) informal care by 1 h was €8.88 (€6.85). Values were associated with a variety of characteristics of the caregiving situation; explanatory variables differed between WTP and WTA valuations. The differences between WTP and WTA valuations were small. Based on sensitivity CV appears to be a useful method to value informal care for use in economic evalations, non‐response, however, remains a matter of concern. Copyright © 2009 John Wiley & Sons, Ltd.