Bilbao-González Amaia, González-Sáenz de Tejada Marta, Ferrer Montse, Ramallo-Fariña Yolanda, Paja-Fano Miguel, García-Forero Carlos, Mestre Daniela, Gorostiza-Hormaetxe Iñigo
Osakidetza Basque Health Service, Research and Innovation Unit, Basurto University Hospital, Bilbao, Spain.
Network for Research on Chronicity, Primary Care, and Health Promotion (RICAPPS), Bilbao, Spain.
J Patient Rep Outcomes. 2025 May 29;9(1):60. doi: 10.1186/s41687-025-00874-5.
The EQ-5D-5L five-dimensional instrument, is one of the most widely used generic preference-based questionnaires to measure health-related quality of life and to estimate utility indices for use in economic evaluation. This study aimed to assess the psychometric properties of the Spanish EQ-5D-5L questionnaire in patients with Diabetes Mellitus (DM) assessing reliability, validity, and item-level properties such as item functioning.
We included 133 patients with DM who completed the EQ-5D-5L, the Audit on Diabetes-Dependent Quality of Life (ADDQoL), the Hospital Anxiety and Depression Scale (HADS), one question about general health and sociodemographic, and clinical data. The reliability was assessed by Cronbach's alpha, and the item functioning by the item response theory (IRT). Convergent validity was tested using the Spearman correlation coefficient between EQ-5D-5L, ADDQoL, HADS and the general health question. We examined known-groups validity by comparing the EQ-5D-5L scores between subgroups defined by age, gender, BMI, regular physical activity, disease duration, glycemic control by glycosylated blood hemoglobin (HbA1c) (%), type of DM, general health and anxiety and depression level using t-test, ANOVA, Wilcoxon or Kruskal-Wallis tests.
The reliability was supported with a Cronbach's alpha of 0.78. The IRT results supported the unidimensionality and showed adequate item functioning, except for the anxiety/depression dimension. The item with highest discriminatory power was usual activities dimension, followed by self-care and mobility dimensions. The EQ-5D-5L showed adequate convergent validity, with high correlation with the ADDQoL, HADS and general health. Older age, women, obese, no regular physical activity, ≥ 10 years of disease duration, poor glycemic control, poorer general health and higher anxiety and depression level linked with lower EQ-5D-5L scores.
These findings support the adequate psychometric properties of the EQ-5D-5L in patients with DM, supporting its use for clinicians and researchers as an outcome measure and for use in economic evaluation studies.
EQ-5D-5L五维度量表是最广泛使用的基于偏好的通用问卷之一，用于测量健康相关生活质量并估计用于经济评估的效用指数。本研究旨在评估西班牙文版EQ-5D-5L问卷在糖尿病（DM）患者中的心理测量特性，评估其信度、效度以及项目水平特性，如项目功能。
我们纳入了133例DM患者，他们完成了EQ-5D-5L、糖尿病相关生活质量评估（ADDQoL）、医院焦虑抑郁量表（HADS）、一个关于总体健康及社会人口学的问题以及临床数据。通过克朗巴哈系数评估信度，通过项目反应理论（IRT）评估项目功能。使用EQ-5D-5L、ADDQoL、HADS与总体健康问题之间的斯皮尔曼相关系数检验收敛效度。我们通过使用t检验、方差分析、威尔科克森检验或克鲁斯卡尔-沃利斯检验，比较由年龄、性别、体重指数、规律体育活动、病程、糖化血红蛋白（HbA1c）（%）控制血糖水平、DM类型、总体健康以及焦虑抑郁水平定义的亚组之间的EQ-5D-5L得分，来检验已知群组效度。
克朗巴哈系数为0.78，支持了信度。IRT结果支持单维度性，除焦虑/抑郁维度外，显示出足够的项目功能。区分能力最高的项目是日常活动维度，其次是自我护理和行动能力维度。EQ-5D-5L显示出足够的收敛效度，与ADDQoL、HADS和总体健康高度相关。年龄较大、女性、肥胖、无规律体育活动、病程≥10年、血糖控制不佳、总体健康较差以及焦虑抑郁水平较高与较低的EQ-5D-5L得分相关。
这些发现支持了EQ-5D-5L在DM患者中具有足够的心理测量特性，支持其作为临床医生和研究人员的结局指标以及用于经济评估研究。
