Societal Preferences for the Surgical Treatment of Basal Cell Carcinoma: Results of a Discrete Choice Experiment

Abstract

Rationale: Several therapeutic options are available to treat basal cell carcinoma, a slowly growing non-melanoma form of skin cancer. In general, a distinction can be made between non-surgical and surgical treatment modalities. Of the last category, Surgical excision (SE) and Mohs Micrographic Surgery (MMS) are perhaps the best well-known. Results of a trial which compared the recurrence rate and costs between MMS and SE showed that from a hospital point of view, it did not seem cost-effective to implement MMS on a large scale for both primary and recurrent BCC. However, it is possible that individuals value other attributes of a surgical treatment than those, which are included in the cost-effectiveness measure.

Objective: The objective of this study was to determine which attributes of a surgical treatment to treat BCC are important and to estimate the willingness to pay. Methods Six attributes and their levels (recurrence rate, duration of surgery, re-excision, waiting time for surgery results, travel time to hospital and the price for surgery) were selected based on a review, a previous randomised clinical trial and a focus group which involved patients who had undergone treatment for removing a BCC. A fractional factorial design was used to produce 32 scenarios which were divided into 16 pair-wise choices. All choice pairs were labelled "option A" and "option B" while a third option "no preference" was also included. Between April and July 2006, data were collected by using telephone interviews. A random effects ordered probit model (Limdep) was used to estimate utilities and calculate the willingness to pay. Results312 respondents were interviewed by telephone (response rate of 48 percent). The model appears to fit the data very well since 78 percent of the observations are correctly predicted. All coefficients were highly significant and of the anticipated negative sign which means that respondents were likely to prefer a surgical treatment with lower recurrence rate, lower surgery time, lower travelling time, less waiting time, no risk for a re-excision and lower costs. The marginal willingness to pay values show that respondents are willing to pay 462 euro for a decrease of 1 percent recurrence percentage,159 euro for a reduction of a week in waiting time for surgery results, 59 euro to avoid a re-excision, 7 euro to have 1 minute less travel time and 6 euro for a decrease of 1 minute in duration of the surgery.

Conclusion: These results show that based on the marginal willingness to pay values, the most important attribute for respondents is the recurrence percentage. However, the model also demonstrates that individuals do value other less health related factors like travel time or the duration of surgery.

Keywords: Basal cell carcinoma, discrete choice experiment, willingness to pay