TY - JOUR
T1 - Eliciting willingness to pay: comparing closed-ended with open-ended and payment scale formats
AU - Frew, Emma
AU - Whynes, DK
AU - Wolstenholme, JL
PY - 2003/4/1
Y1 - 2003/4/1
N2 - Willingness to pay (WTP) is increasingly being used as a measure of valuation in health technology assessment. A variety of formats for eliciting values are available, although the relative virtues of each remain the subject of methodological controversy. This article compares valuation results obtained using a WTP survey instrument in a closed-ended format with those obtained from instruments using open-ended and payment scale formats. Samples of subjects were drawn from a general population, and all were asked to value the same intervention--alternative methods of screening for colorectal cancer. It was discovered that, whereas the open-ended and payment scale formats produced broadly similar valuations, the closed-ended format produced significantly higher WTP valuations and different justifications for those valuations. It is hypothesized that anchoring and yea-saying effects explain these differences and that the closed-ended format triggers a different response mode in subjects.
AB - Willingness to pay (WTP) is increasingly being used as a measure of valuation in health technology assessment. A variety of formats for eliciting values are available, although the relative virtues of each remain the subject of methodological controversy. This article compares valuation results obtained using a WTP survey instrument in a closed-ended format with those obtained from instruments using open-ended and payment scale formats. Samples of subjects were drawn from a general population, and all were asked to value the same intervention--alternative methods of screening for colorectal cancer. It was discovered that, whereas the open-ended and payment scale formats produced broadly similar valuations, the closed-ended format produced significantly higher WTP valuations and different justifications for those valuations. It is hypothesized that anchoring and yea-saying effects explain these differences and that the closed-ended format triggers a different response mode in subjects.
UR - http://www.scopus.com/inward/record.url?scp=0037348260&partnerID=8YFLogxK
U2 - 10.1177/0272989X03251245
DO - 10.1177/0272989X03251245
M3 - Article
C2 - 12693877
SN - 1552-681X
VL - 23
SP - 150
EP - 159
JO - Medical Decision Making
JF - Medical Decision Making
IS - 2
ER -