Putnam, 22-24 Torrington Place, Fitzrovia, London, WC1E 7HJ, UK.
Bristol Myers Squibb, Uxbridge, England, UK.
Health Qual Life Outcomes. 2024 Sep 20;22(1):81. doi: 10.1186/s12955-024-02294-3.
The minimal important difference (MID) is a useful tool to interpret changes in patients' health-related quality of life. This study aims to estimate MIDs for interpreting within-patient change for both components of the EQ-5D-5L questionnaire [EQ-Visual Analogue Scale (EQ-VAS) and utility index] and domains of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) for cancer patients.
Data were obtained from the Cancer 2015 dataset, a longitudinal cohort of Australian cancer patients. Anchor-based approaches were used to estimate MIDs for the EQ-5D-5L index-based utility index [Australia and the United States (US) tariff sets], EQ-VAS scores, and the EORTC QLQ-C30. Clinical [Eastern Cooperative Oncology Group (ECOG) performance status] and patient-reported (items 29 and 30 of the EORTC QLQ-C30 and the EQ-VAS) anchors were assessed for appropriateness by their correlation strength. Clinical change groups (CCGs) were defined a priori for improvement and deterioration based on estimates used in previous literature. MIDs were estimated via linear regression and distribution-based methods.
For the index-based utility scores in Australia, the anchor-defined MID estimates were 0.01 to 0.06 for improvement and - 0.04 to -0.03 for deterioration, with a weighted value of 0.03 for improvement and deterioration. The EQ-VAS MID estimate was 5 points for both improvement and deterioration. For the EORTC QLQ-C30, changes of at least 3.64 (improvement) and - 4.28 (deterioration) units on the physical functioning scale, 6.31 (improvement) and - 7.11 (deterioration) units on the role functioning scale, 4.65 (improvement) and - 3.41 (deterioration) units on the emotional functioning scale, and 5.41 (improvement) and - 5.56 (deterioration) units on the social functioning scale were estimated to be meaningful.
This study identified lower MIDs for the EQ-5D-5L utility index, EQ-VAS, and EORTC QLQ-C30 domain scores, than those reported previously. The use of a real-world cancer-specific panel dataset may reflect smaller MID estimates that are more applicable to cancer patients in the clinical practice, rather than using MIDs that have been estimated from clinical trials.
最小有意义差异（MID）是解释患者健康相关生活质量变化的有用工具。本研究旨在为澳大利亚癌症患者的 EQ-5D-5L 问卷[EQ-视觉模拟量表（EQ-VAS）和效用指数]和欧洲癌症研究与治疗组织生活质量问卷核心 30 项（EORTC QLQ-C30）的各个领域的患者内变化，估算 MID。
数据来自澳大利亚癌症 2015 年数据集，这是一个澳大利亚癌症患者的纵向队列。使用基于锚定的方法来估算 EQ-5D-5L 指数效用指数[澳大利亚和美国（US）关税集]、EQ-VAS 评分和 EORTC QLQ-C30 的 MID。临床[东部合作肿瘤学组（ECOG）表现状态]和患者报告（EORTC QLQ-C30 的项目 29 和 30 和 EQ-VAS）锚定通过其相关性强度来评估是否合适。根据以前文献中的估计，预先定义了临床变化组（CCG）用于改善和恶化。MID 通过线性回归和基于分布的方法来估算。
对于澳大利亚的指数效用评分，锚定定义的 MID 估计值为改善 0.01 至 0.06，恶化-0.04 至-0.03，加权值为改善 0.03 和恶化。EQ-VAS MID 估计值为改善和恶化均为 5 分。对于 EORTC QLQ-C30，身体功能量表上至少改善 3.64（改善）和恶化-4.28（恶化）单位，角色功能量表上至少改善 6.31（改善）和恶化-7.11（恶化）单位，情绪功能量表上至少改善 4.65（改善）和恶化-3.41（恶化）单位，社交功能量表上至少改善 5.41（改善）和恶化-5.56（恶化）单位，被认为具有意义。
本研究确定了 EQ-5D-5L 效用指数、EQ-VAS 和 EORTC QLQ-C30 域评分的较低 MID，低于之前报道的 MID。使用真实世界的癌症特定面板数据集可能反映了更小的 MID 估计值，这些估计值更适用于临床实践中的癌症患者，而不是使用从临床试验中估算出的 MID。
