Do Model-Based Studies in Chronic Obstructive Pulmonary Disease Measure Correct Values of Utility? A Meta-Analysis.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a progressive chronic disease that has considerable impact on utility-based health-related quality of life. Utility is a key input of many decision analytic models used for economic evaluations. OBJECTIVE: To systematically review COPD-related utilities and to compare these with alternative values used in decision models. METHODS: The literature review comprised studies that generated utilities for COPD-related stages based on EuroQol five-dimensional questionnaire surveys of patients and of decision models of COPD progression that have been used for economic evaluations. The utility values used in modeling studies and those from the meta-analysis of actual patient-level studies were compared and differences quantified. RESULTS: Twenty decision modeling studies that used utility value as an input parameter were found. Within the same span of publication period, 13 studies involving patient-level utility data were identified and included in the meta-analysis. The estimated mean utility values ranged from 0.806 (95% confidence interval [CI] 0.747-0.866) for stage I to 0.616 (95% CI 0.556-0.676) for stage IV. The utility scores for comparable stages in modeling studies were different (significant difference 0.045 [95% CI 0.041-0.052] for stage III). Modeling studies consistently used higher utility values than the average reported patient-level data. CONCLUSIONS: COPD decision analytic models are based on a limited range of utility values that are systematically different from average values estimated using a meta-analysis. A more systematic approach in the application of utility measures in economic evaluation is required to appropriately reflect current literature.