Hypothetical versus real willingness to pay in the health care sector: results from a field experiment

We conducted a field experiment comparing hypothetical and red purchase dec isions for a pharmacist provided asthma management program among 172 subjec ts with asthma. Subjects received either a dichotomous choice contingent va luation question or were given the opportunity to actually enroll in the pr ogram. Three different prices were used: US$ 15, 40, and 80. In the hypothe tical group, 38% of subjects said that they would purchase the good at the stated price, but only 12% of subjects in the real group purchased the good (p = 0.000), We cannot, however, reject the null hypothesis that "definite ly sure" hypothetical yes responses, as identified in a follow-up question, correspond to real yes responses, We conclude that the dichotomous choice contingent valuation method overestimates willingness to pay, but that it m ay be possible to correct for this overestimation by sorting out "definitel y sure" yes responses. (C) 2001 Elsevier Science B.V. All rights reserved.