Luo Nan, Cheung Yin Bun, Ng Raymond, Lee Chun Fan
Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore.
Center for Quantitative Medicine, Duke-NUS Graduate Medical School, Singapore, Singapore.
Health Qual Life Outcomes. 2015 Oct 5;13:166. doi: 10.1186/s12955-015-0361-y.
Utility values of health states defined by health-related quality of life instruments can be derived from either direct valuation ('valuation-derived') or mapping ('mapping-derived'). This study aimed to compare the utility-based EQ-5D-5L index scores derived from the two approaches as a means to validating the mapping function developed by van Hout et al for the EQ-5D-5L instrument.
This was an observational study of 269 breast cancer patients whose EQ-5D-5L index scores were derived from both methods. For comparing discriminatory ability and responsiveness to change, multivariable regression models were used to estimate the effect sizes of various health indicators on the index scores. Agreement and test-retest reliability were examined using intraclass correlation coefficient (ICC). Whenever appropriate, the 90% confidence intervals (90% CI) were compared to predefined equivalence margins.
The mean difference in and ICC between the valuation- and mapping-derived EQ-5D-5L index scores were 0.015 (90% CI = 0.006 to 0.024) and 0.915, respectively. Discriminatory ability and responsiveness of the two indices were equivalent in 13 of 15 regression analyses. However, the mapping-derived index score was lower than the valuation-derived index score in patients experiencing extreme health problems, and the test-retest reliability of the former was lower than the latter, for example, their ICCs differed by 0.121 (90% CI = 0.051 to 0.198) in patients who reported no change in performance status in the follow-up survey.
This study provided the first evidence supporting the validity of the mapping function for converting EQ-5D-5L profile data into a utility-based index score.
健康相关生活质量工具所定义的健康状态的效用值可通过直接估值（“估值衍生”）或映射（“映射衍生”）获得。本研究旨在比较两种方法得出的基于效用的EQ-5D-5L指数得分，以此验证van Hout等人针对EQ-5D-5L工具开发的映射函数。
这是一项对269名乳腺癌患者的观察性研究，其EQ-5D-5L指数得分通过两种方法得出。为比较区分能力和对变化的反应性，使用多变量回归模型估计各种健康指标对指数得分的效应大小。使用组内相关系数（ICC）检验一致性和重测信度。在适当情况下，将90%置信区间（90%CI）与预先定义的等效界限进行比较。
估值衍生和映射衍生的EQ-5D-5L指数得分的平均差异和ICC分别为0.015（90%CI = 0.006至0.024）和0.915。在15项回归分析中的13项中，两个指数的区分能力和反应性相当。然而，在经历极端健康问题的患者中，映射衍生的指数得分低于估值衍生的指数得分，且前者的重测信度低于后者，例如，在随访调查中报告功能状态无变化的患者中，它们的ICC相差0.121（90%CI = 0.051至0.198）。
本研究提供了首个证据，支持将EQ-5D-5L简表数据转换为基于效用的指数得分的映射函数的有效性。
