The EQ-5D and SF-6D are 2 health-related quality-of-life indexes that provide preference-weighted measures for use in cost-effectiveness analyses.
The National Cancer Institute's Cancer Care Outcomes Research and Surveillance (CanCORS) Consortium included the EQ-5D and SF-12v2 in their survey of newly diagnosed lung cancer patients. Utilities were calculated from patient-provided scores for each domain of the EQ-5D or the SF-6D. Utilities were calculated for categories of cancer type, stage, and treatment.
There were 5015 enrolled lung cancer patients with a baseline survey in CanCORS; 2396 (47.8%) completed the EQ-5D, and 2344 (46.7%) also completed the SF-12v2. The mean (standard deviation) utility from the EQ-5D was 0.78 (0.18), and from the SF-6D (derived from SF-12v2) was 0.68 (0.14). The EQ-5D demonstrated a ceiling effect, with 20% of patients reporting perfect scores, translating to a utility of 1.0. No substantial SF-6D floor effects were noted. Utilities increased with age and decreased with stage and comorbidities. Patient-reported (EQ-5D) visual analog scale scores for health status had a moderate (r = 0.48, p < 0.0001) positive correlation with utilities. A subset (n = 1474) completed follow-up EQ-5D questionnaires 11-13 months after diagnosis. Among these patients, there was a nonsignificant decrease in mean utility for stage IV and an increase in mean utility for stages I, II, and III.
This study generated a catalog of community-weighted utilities applicable to societal-perspective cost-effectiveness analyses of lung cancer interventions and compared utilities based on the EQ-5D and SF-6D. Potential users of these scores should be aware of the limitations and think carefully about their use in specific studies.