Validity and reliability of the Health-Related Quality of Life Instrument with 8 Items (HINT-8) in Korean breast cancer patients

Objectives This study evaluated the validity and reliability of the Health-Related Quality of Life Instrument with 8 Items (HINT-8) in postoperative breast cancer patients in South Korea. Methods The study included 300 breast cancer patients visiting a tertiary hospital. We measured health-related quality of life (HRQoL) using the HINT-8, the 5-level EQ-5D version (EQ-5D-5L), and the Functional Assessment of Cancer Therapy-Breast (FACT-B). Discriminatory ability, known-group validity, and convergent validity were assessed. Reliability was evaluated with the Cohen kappa, weighted kappa, and intraclass correlation coefficient (ICC). Results The EQ-5D-5L indexes (p