An Assessment of the Burden of Migraine using the Willingness to Pay Model

Abstract

Willingness to pay methods measure treatment preferences and also measure the burden of illness in economic terms. We used a contingent valuation method to measure migraine sufferers' willingness to pay (WTP) for acute medication for their most severe headache attacks, based on various profiles of treatment benefits and the characteristics of the migraine sufferer. Subjects were identified from a population-based database of migraine sufferers, previously recruited by random digit dialling. Telephone interviews ( n = 1428) were used to gather demographic and headache characteristics. Subjects who met the International Headache Society criteria for migraine with or without aura and satisfied the other inclusion criteria based on telephone interview ( n = 312) were invited to participate in a mailed questionnaire study. The questionnaire was mailed to the 310 subjects who agreed to participate and 201 (65%) surveys were returned. The survey included questions on the demographics, the migraine characteristics, and the psychological disposition of the respondents. WTP for an acute migraine treatment with 14 different hypothetical treatment profiles was explored. Responders and non-responders to the survey were generally similar. The newly designed WTP questionnaire had high internal consistency (Cronbach's α 0.90) and test-retest reliability (Spearman's corrleation coefficients 0.71-0.77). Study subjects were willing to pay a median price of 5 for a migraine treatment that provided complete relief in 30 min and worked 100% of the time, with no side-effects and no headache recurrence. Median WTP decreased as treatment attributes deviated from this ideal. For example, WTP declined to a median of 1 for complete relief in 2 h and to $0.25 for complete relief in 4 h. All of the medication attributes powerfully influenced WTP. Several variables predicted WTP including current payment for medication, MIDAS (Grade III), and those with headaches of long duration. Subjects who employed a greater number of coping skills were less willing to pay. Patient demographics and migraine severity predict WTP, but treatment attributes were also important. As treatment improves, WTP for migraine medications is likely to increase.