COMPARING COMMUNITY-PREFERENCE–BASED AND DIRECT STANDARD GAMBLE UTILITY SCORES: EVIDENCE FROM ELECTIVE TOTAL HIP ARTHROPLASTY

OBJECTIVES: Do utility scores based on patient preferences and scores based on community preferences agree? The purpose is to assess agreement between directly measured standard gamble (SG) utility scores and utility scores from the Health Utilities Index Mark 2 (HUI2) and Mark 3 (HUI3) systems. METHODS: Patients were assessed repeatedly throughout the process of waiting to see a surgeon, waiting for surgery, and recovery after total hip arthroplasty (THA). Group mean scores are compared using paired t-tests. Agreement is assessed using the intraclass correlation coefficient (ICC). RESULTS: The mean SG, HUI2, and HUI3 (SD) scores at assessment 1 are 0.62 (0.31), 0.62 (0.19), and 0.52 (0.21); n=103. At assessment 2, the means are 0.67 (0.30), 0.68 (0.30), and 0.58 (0.22); n=84. There are no statistically significant differences between group mean SG and HUI2 scores. Mean SG and HUI3 scores are significantly different. ICCs are low. CONCLUSIONS: At the mean level for the group, SG and HUI2 scores match closely. At the individual level, agreement is poor. HUI2 scores were greater than HUI3 scores. HUI2 and HUI3 are appropriate for group level analyses relying on community preferences but are not a good substitute for directly measured utility scores at the individual level.