Department of Clinical Pharmacy, MAHSA University, Selangor, Malaysia; Department of Clinical Pharmacy and Pharmacy Practice, University of Jos, Plateau State, Nigeria.
Department of Clinical Pharmacy, MAHSA University, Selangor, Malaysia.
Value Health Reg Issues. 2020 Sep;22:15-22. doi: 10.1016/j.vhri.2019.08.478. Epub 2020 Jan 31.
To evaluate the validity and reliability of the 5-level EuroQol 5-dimensional questionnaire (EQ-5D-5L) through classical test theory and the Rasch measurement model.
Three hundred patients treated for uncomplicated malaria in selected primary healthcare facilities of Plateau state, Nigeria, completed the EQ-5D-5L scale. Classical test theory was used to establish validity and Cronbach's alpha reliability of the scale. Rasch analysis was used to confirm the unidimensionality, item fitness, item and person separations and reliabilities, and targeting of item difficulty to patient ability levels and presentation on Wright map (item-person map).
The outcome of classical test theory revealed unidimensional scale with average variance extracted values > 0.5, and the square root of the average variance extracted for construct was greater than the correlation coefficients, indicating convergent and discriminant validities of the scale whose Cronbach's alpha coefficient (α) was 0.87. Rasch analysis indicated variance explained values of 88.3% and the eigenvalues of the first contrast was 1.3, further confirming the unidimensionality of the scale, whose fit index values were within accepted ranges. The high item and person separation and reliability values indicated the instrument's strength in detecting and evenly spreading items and persons on the Wright map based on item difficulty and the respondents' ability levels, respectively.
The EQ-5D-5L scale performed well in uncomplicated malaria, hence, it is recommended for use in the assessment of health-related quality of life in this patient population.
通过经典测试理论和 Rasch 测量模型评估 5 级欧洲五维健康量表（EQ-5D-5L）的有效性和可靠性。
在尼日利亚高原州选定的初级保健机构接受治疗的 300 名无并发症疟疾患者完成了 EQ-5D-5L 量表。经典测试理论用于建立量表的有效性和 Cronbach's alpha 可靠性。Rasch 分析用于确认量表的单维性、项目拟合度、项目和个体分离度和可靠性，以及项目难度对患者能力水平的针对性和 Wright 图（项目-个体图）上的呈现。
经典测试理论的结果显示出具有平均方差提取值>0.5 的单维量表，且结构的平均方差提取的平方根大于相关系数，表明量表具有收敛和判别有效性，其 Cronbach's alpha 系数（α）为 0.87。Rasch 分析表明解释方差值为 88.3%，第一对比的特征值为 1.3，进一步证实了量表的单维性，其拟合指数值在可接受范围内。高的项目和个体分离和可靠性值表明，该工具在根据项目难度和受访者的能力水平，在 Wright 图上检测和均匀分布项目和个体方面具有优势。
EQ-5D-5L 量表在无并发症疟疾中表现良好，因此建议在评估该患者群体的健康相关生活质量时使用。
