Department of Biostatistics, Singapore Clinical Research Institute, Singapore; Centre for Quantitative Medicine, Duke-NUS Medical School, Singapore; Tampere Center for Child Health Research, University of Tampere and Tampere University Hospital, Tampere, Finland.
Health Services Research Centre, Akershus University Hospital, Lørenskog, Norway; Department of Health Management and Health Economics, University of Oslo, Oslo, Norway.
Value Health. 2019 Mar;22(3):370-376. doi: 10.1016/j.jval.2018.10.002. Epub 2018 Nov 12.
To evaluate the discriminative ability of negative values measured in 5-level EuroQol 5-dimensional questionnaire (EQ-5D-5L) value set studies.
This is a secondary analysis of EQ-5D-5L value set studies from Singapore, the Netherlands, China, Thailand, and Canada in which health state values were elicited from a general population sample using a composite time trade-off (TTO) method. Mean values were calculated for health states with same severity. The association between the mean values and severity was evaluated using Pearson correlation (r). A linear mixed model using severity as the fixed effect was fitted for values. The analyses were performed separately for positive values (from a conventional TTO for health states considered "better than death") and negative values (from a lead time TTO for health states considered "worse than death").
In Singapore (N = 1000; negative values 32.6%), the mean decreased with severity from 0.89 to 0.21 for positive values and increased with severity from -0.98 to -0.89 for negative values. The correlation between values and severity was much lower for negative values (r = -0.016) than for positive values (r = -0.614). The coefficient of severity in the linear mixed model for negative values was much smaller (coefficient = -0.009; pseudo-R < 0.001) compared with the model for positive values (coefficient = -0.041; pseudo-R = 0.337). Results using data sets from the other countries were similar.
Negative values are not associated with severity of health states in EQ-5D-5L valuation studies, suggesting poor discriminative ability of the lead time TTO method in valuing health states considered worse than death.
评估五级欧洲五维健康量表（EQ-5D-5L）效用值测量中的负值的区分能力。
这是对来自新加坡、荷兰、中国、泰国和加拿大的 EQ-5D-5L 效用值研究的二次分析，其中使用综合时间权衡（TTO）方法从一般人群样本中得出健康状态值。对于具有相同严重程度的健康状态，计算平均值。使用 Pearson 相关系数（r）评估平均值与严重程度之间的关联。使用严重程度作为固定效应，为数值拟合线性混合模型。分别对正值（来自被认为“优于死亡”的健康状态的传统 TTO）和负值（来自被认为“劣于死亡”的健康状态的领先时间 TTO）进行分析。
在新加坡（N=1000；负值 32.6%），正值的平均值随严重程度从 0.89 降至 0.21，负值的平均值随严重程度从-0.98 增至-0.89。负值与严重程度之间的相关性远低于正值（r=-0.016 比 r=-0.614）。负值的线性混合模型中严重程度的系数要小得多（系数=-0.009；伪 R<0.001），而正值的模型中严重程度的系数则要大得多（系数=-0.041；伪 R=0.337）。来自其他国家的数据集中的结果也相似。
在 EQ-5D-5L 估值研究中，负值与健康状态的严重程度无关，这表明在评估被认为劣于死亡的健康状态时，领先时间 TTO 方法的区分能力较差。
