A willingness-to-pay (WTP) survey measures the value of a given intervention in money terms. We examined the WTP of Canadian patients with rheumatoid arthritis (RA) for a hypothetical cure for RA under private and public scenarios. The validity of the survey was explored by studying the association between WTP and variables thought to be associated with WTP and randomly-varied variables of the survey materials.
A telephone survey was carried out in a sample of 121 patients with RA from 5 rheumatologists affiliated with the McGill University Health Centre. In advance, patients had been sent a 4-page brochure providing a comprehensive description of the disease (including photos or no photos). The hypothetical cure for RA was presented through 2 scenarios: a private insurance implying an annual premium and a public coverage requiring additional income taxes. The survey included questions related to their WTP, socioeconomic status (ability to pay), general health, opinion about the performance of the healthcare system, and their opinion about the difficulty of the survey. For elicitation of WTP, patients were randomized to one of 3 payment cards. Mailed questionnaires concerning RA health status were also completed. A series of univariate comparisons and multivariate ordered logit regressions were carried out to examine the association of WTP and patient and study variables.
Patients were willing to pay annually significantly more for the private program (mean 1190 Canadian dollars) than for the public program (mean 502 Canadian dollars). Annual WTP was associated with age, household income, site of care (private program), private health insurance, opinion about the performance of the public healthcare system (public program), and presence of brochure photos. The payment card did not affect WTP for either program.
The WTP survey was well understood and accepted by the patients with RA. Although measures of RA-specific health status (e.g., Health Assessment Questionnaire) were not found to be associated with WTP, many variables thought to be associated with WTP were found to be related in the expected directions. Since WTP for the private program was higher than that for the public program, our study design did not fully capture altruistic valuations of RA patients. Thus, our estimates represent a lower bound on patients' WTP for an RA cure.