Rating of arthritis health states by patients, physicians, and the general public. Implications for cost-utility analyses

We elicited preferences for 2 arthritis health states (mild and severe) using visual analog scales, time tradeoff, and standard gamble by interviewing 104 individuals from the general public, 51 patients with rheumatoid arthritis, and 43 health professionals. The health scenarios were based on attributes described in a health status classification instrument, the EuroQol (EQ-5D). In addition, we compared the ratings in our survey with those obtained for the same scenarios by one of the scoring algorithms used for the EQ-5D (York weights). Statistically significant differences were observed in the ratings of the health scenarios, mostly for the severe vignette. Most of the variability was related to the method employed. The cost-utility ratio for a hypothetical intervention varied according to the method employed to determine the utility of the health states, from $15,000 to $111,000 US per quality adjusted life year (QALY). Patient derived weights resulted in cost-utility ratios that ranged from $39,000 to $222,000. Our findings show that the methodology used to elicit and analyze utilities can have substantial implications in the economic evaluation of interventions for patients with RA.