Does the Inclusion of a Cost Attribute Result in Different Preferences for the Surgical Treatment of Primary Basal Cell Carcinoma?: A Comparison of Two Discrete-Choice Experiments

Background: Nowadays, an increasing number of discrete-choice experiments (DCEs) incorporate cost as an attribute. However, the inclusion of a cost attribute, particularly within collectively funded healthcare systems, can be challenging because health services or goods are generally not traded in a market situation and individuals are not used to paying for a service or a good at the point of consumption. Objective: To examine whether the inclusion of a cost attribute in a DCE results in different preferences regarding a surgical treatment for primary basal cell carcinoma (BCC) compared with a DCE without a cost attribute. Methods: A randomized study was performed in which the impact of a cost attribute on the general public's preferences for a surgical treatment (Mohs micrographic surgery [MMS] or standard excision [SE]) to remove BCC was examined. This was done by comparing the outcomes of two DCEs, one with a cost attribute (DCE_cost) and one without (DCE_nocost). Six attributes (recurrence, re-excision, travel time, surgical time, waiting time for surgical results, costs) and their levels were selected, based on results of a clinical trial, a cost-effectiveness study, a review and a focus group of patients who had recently received treatment for BCC. Outcomes of both DCEs were compared in terms of theoretical validity, relative importance of the attributes and the rank order of preferences. Results: A total of 615 respondents (n - 303 for DCE_nocost; n - 312 for DCE_cost) were interviewed by telephone. This gave an overall response rate of 38%.  Respondents in DCE_nocost preferred a surgical treatment with a lower probability of recurrence, lower surgery time, lower waiting time and no risk for a re-excision. Respondents in DCE_cost showed the same preferences, but also preferred a treatment with less travel time and lower costs. Overall, respondents in both DCEs showed the same preference for a surgical treatment: MMS was preferred over SE. Conclusion: Results suggest that, in this population, the inclusion of a cost attribute in a DCE leads to the same preference regarding a surgical treatment to remove BCC as a DCE without a cost attribute. However, further research in different settings is needed to confirm these findings.