Measurement properties of the EQ-5D-5L and SF-6D in measuring the health-related quality of life of non-small cell lung cancer patients on active treatments in China

Lung cancer is the leading cause of cancer-related death globally, including China, with non-small cell lung cancer (NSCLC) accounting for 85% of cases. Novel NSCLC drugs need cost-utility analysis (CUA) for Chinese reimbursement. CUA relies on health utility values, but the only measures with value sets for Chinese populations, i.e., EQ-5D-5L and SF-6D, lack NSCLC-specific reliability and validity comparison evidence. This study examined their measurement properties in Chinese patients with NSCLC. A cross-sectional survey was conducted across 18 provincial-level jurisdictions in China (2022.10–2024.03) with 947 patients from 20 hospitals. EQ-5D-5L, SF-6D, and QLQ-C30 were administered to patients, and a total of 886 patients with complete responses to all three aforementioned measures were included in the analysis of this study. Measurement properties were evaluated via ceiling/floor effects, convergent validity (with QLQ-C30), known-groups validity (gender, age, cancer stage, surgery, brain metastasis, bone metastasis, and COVID-19 infection history), and Shannon (H′) and evenness (J′) indices. Among the analysis sample (n = 886), participants were 36.5% female with a mean age of 61.5 years and a mean disease duration of 1.8 years; 64.1% had stage IV disease. Ceiling effects for the EQ-5D-5L and SF-6D were 26.07% and 3.50%, respectively. Both tools showed moderate-to-strong correlations with relevant QLQ-C30 dimensions (|rho| = 0.58–0.84, all p < 0.001). For known-groups validity, small-to-medium effect sizes were found for subgroups of age, cancer stage, operation, and bone metastasis for EQ-5D-5L; and cancer stage, operation, bone metastasis, and COVID-19 infection history for SF-6D. Regarding informativity, H′/J′ ranged from 1.061/0.457 for “Self-care” to 1.737/0.748 for “Pain/discomfort” for EQ-5D-5L, and 1.925/0.829 for “mental health” to 2.223/0.957 for “social functioning” for SF-6D. Both the EQ-5D-5L and SF-6D have robust measurement properties for assessing health status in Chinese NSCLC patients. In China, economic evaluations for new drug reimbursement require reliable health utility data. This study was motivated by the lack of evidence on the measurement properties of the two primary Chinese preference-based measures—the EQ-5D-5L and SF-6D—in patients with non-small cell lung cancer (NSCLC). We aimed to address this gap by systematically comparing their performance to inform their suitability for cost-utility analysis. A cross-sectional survey of 947 NSCLC patients from 20 Chinese hospitals was conducted. After screening, 886 participants who had completed the EQ-5D-5L, SF-6D, and the QLQ-C30 were obtained. We evaluated response patterns, construct validity, known-groups validity, and informativity. Both instruments demonstrated robust and comparable measurement properties for assessing HRQoL in Chinese NSCLC patients. A key difference was the significantly higher ceiling effect for the EQ-5D-5L (26.07%) versus the SF-6D (3.50%). Both measures showed moderate-to-strong correlations with relevant QLQ-C30 domains, supporting construct validity. Known-groups validity was confirmed, as both effectively distinguished patients across clinical subgroups such as cancer stage and surgery status. Overall, the SF-6D exhibited marginally better informativity and discriminatory power across its dimensions. In conclusion, both the EQ-5D-5L and SF-6D are valid for deriving health utilities in Chinese NSCLC patients and are suitable for economic evaluations. The selection between them may involve weighing their relative strengths regarding ceiling effects and validated performance. These results provide essential evidence for health economic research and policy-making regarding NSCLC treatment in China.