Kay Stephen, Ferreira Alberto
Adelphi Real World , Bollington , UK and.
Ophthalmic Epidemiol. 2014 Apr;21(2):66-78. doi: 10.3109/09286586.2014.888456. Epub 2014 Feb 25.
To develop a mapping algorithm for the estimation of EQ-5D-based utility scores from observed 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) scores, a disease-specific, patient-reported outcome measure used in several retinal disorders to evaluate vision-specific functioning.
The dataset comprised 951 paired EQ-5D/NEI VFQ-25 observations from 344 patients in RESTORE, a 12-month, randomized, double-blind trial in individuals with visual impairment due to diabetic macular edema. EQ-5D index scores (utilities) were calculated based on the UK tariff. We evaluated 11 models using predictor sets based on the NEI VFQ-25 subscales to estimate utility as a function of NEI VFQ-25 score, based on four modeling techniques. Model performance was assessed by 10-fold cross-validation comparing root mean squared error (RMSE), mean absolute error (MAE) and correlation with EQ-5D score (Pearson and Spearman correlation coefficients).
Mapping results were similar across all techniques and predictor sets. The reverse two-part generalized estimating equation model used fewest predictors and had the best predictive performance (RMSE 0.200, MAE 0.140). Predicted and original EQ-5D values were not strongly correlated (squared Spearman correlation coefficient, 0.34).
Although mapping disease-specific instruments to EQ-5D utilities is a preferred method by some reimbursement bodies, finding an appropriate mapping equation is not straightforward. In this study, mapping NEI VFQ-25 scores to EQ-5D utilities provided low predictive power, independent of the modeling methodology applied, suggesting an inability of the EQ-5D to discriminate vision-related activities, and highlighting that mapping exercises may lead to inaccurate utility values that do not represent patients' preferences.
开发一种映射算法，用于根据观察到的25项美国国立眼科研究所视觉功能问卷（NEI VFQ - 25）得分来估计基于EQ - 5D的效用分数，NEI VFQ - 25是一种特定疾病的、患者报告的结局指标，用于多种视网膜疾病以评估特定视力功能。
数据集包括来自RESTORE研究中344例患者的951对EQ - 5D/NEI VFQ - 25观察值，RESTORE是一项为期12个月的随机双盲试验，受试对象为因糖尿病性黄斑水肿导致视力受损的个体。基于英国关税计算EQ - 5D指数得分（效用）。我们基于四种建模技术，使用基于NEI VFQ - 25分量表的预测变量集评估了11种模型，以将效用估计为NEI VFQ - 25得分的函数。通过10折交叉验证评估模型性能，比较均方根误差（RMSE）、平均绝对误差（MAE）以及与EQ - 5D得分的相关性（Pearson和Spearman相关系数）。
所有技术和预测变量集的映射结果相似。反向两部分广义估计方程模型使用的预测变量最少，且具有最佳预测性能（RMSE为0.200，MAE为0.140）。预测的和原始的EQ - 5D值相关性不强（Spearman相关系数平方为0.34）。
尽管将特定疾病的工具映射到EQ - 5D效用是一些报销机构青睐的方法，但找到合适的映射方程并非易事。在本研究中，将NEI VFQ - 25得分映射到EQ - 5D效用的预测能力较低，与所应用的建模方法无关，这表明EQ - 5D无法区分与视力相关的活动，并突出显示映射练习可能导致不代表患者偏好的不准确效用值。
