Responsiveness of the generic EQ-5D summary measure compared to the disease-specific EORTC QLQ C-30

Introduction: We investigated whether the sensitivity of the generic health-related quality of life (HRQoL) EQ-5D summary measure (or index) to detect changes over time in a clinical setting is comparable with that of a disease-specific HRQoL questionnaire. Methods: Patients with liver metastases (n = 75) filled out the five domains of the EQ-5D self-classifier, the EQ VAS, and the EORTC QLQ C-30 (a disease-specific (cancer) HRQoL questionnaire). The HRQoL instruments were completed before intervention, and 1/2 month and 3 and 6 months after intervention. Three analyses were performed. First, the EQ-5D index (based on self-classification) was compared to the EQ VAS. Second, the EQ-5D domains were compared to corresponding EORTC QLQ C-30 scales. Third, EQ-5D index and EQ VAS were compared with the EORTC QLQ C-30 global health-status scale. Effect size was chosen as the metric of responsiveness. Results: The EQ-5D index was slightly less responsive than the EQ VAS. Overall, the responsiveness of the EQ-5D index and EQ VAS was equal to the EORTC QLQ C-30 global health-status scale. Conclusion: Despite its generic principle and the apparent crudeness of its framework, the responsiveness of the EQ-5D proved to be comparable to that of a disease-specific HRQoL questionnaire in this specific clinical setting.