Willingness of patients with ankylosing spondylitis to pay for inpatient treatment is influenced by the treatment environment and expectations of improvement.

OBJECTIVE To assess the willingness to pay (WTP) for treatment in a spa resort of patients with ankylosing spondylitis (AS) and to assess if the experience of a spa influences the WTP. METHODS 120 patients participating in a randomised trial comparing 3 weeks' treatment in a spa resort in Austria or in the Netherlands with a control group completed a WTP questionnaire before and after spa treatment. Patients indicated on a payment card the maximal co-payment they wanted to contribute for three scenarios that included (a) two levels of improvement in pain and stiffness and (b) two treatment environments: a rehabilitation hospital and a spa resort. RESULTS At baseline, patients wanted to contribute more for the same improvement after treatment in a spa resort compared with a rehabilitation hospital (p<0.003), and were prepared to pay more when expected effects were higher (p<0.001). No differences were found between men and women, pain, or income. After the trial none of the treatment groups showed a change in their WTP. CONCLUSION The WTP of patients with AS for inpatient treatment is influenced by the treatment environment and the expected improvement. Experiencing treatment in a spa resort does not influence the co-payment.