A Randomized Multicenter Trial to Evaluate Simple Utility Elicitation Techniques in Patients With Gastroesophageal Reflux Disease
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BACKGROUND: Despite recommendations that patients rating their own health using utility and preference measures such as the feeling thermometer (FT) and standard gamble (SG) should also rate hypothetical marker states, little evidence supports marker state use. We evaluated whether the administration of marker states improves measurement properties of the FT and SG. METHODS: We randomized 217 patients with gastroesophageal reflux disease to complete the FT (self-administered) and SG with marker states (FT+ / SG+, n = 112) or without marker states (FT- / SG-, n = 105) before and after 4 weeks of treatment with a proton pump inhibitor, esomeprazole. Patients also completed other health-related quality of life instruments. RESULTS: The use of marker states did not influence baseline utility scores (FT+ 0.66, FT- 0.68; SG+ 0.77, SG- 0.78, on a scale from 0 [dead] to 1.0 [full health]). Improvement after therapy was 0.21 in FT+ and 0.15 in FT- (both P < 0.001; difference between FT+ and FT- = 0.06, P = 0.02). Improvement in SG+ was 0.07 (P < 0.001) and 0.06 in SG- (P = 0.003) (difference between SG+ and SG- = 0.01, P = 0.63). Correlations with other health-related quality of life scores were generally stronger, with some statistically significant differences in correlations, for FT+ compared with FT-, but tended to be weaker for SG+ compared with SG-. CONCLUSION: The administration of marker states improved the responsiveness and validity of the FT but not of the SG. Decisions about administering marker states should depend on whether the FT and SG is of primary interest and the importance of optimal validity and responsiveness relative to competing objectives such as efficiency.