Ophthalmology Unit, Hospital de la Esperanza, MAR Health Park, Barcelona, Spain.
Department of Optics and Optometry, Universitat Politècnica de Catalunya, Terrassa, Spain.
J Optom. 2022 Jul-Sep;15(3):199-209. doi: 10.1016/j.optom.2021.01.004. Epub 2021 Apr 18.
To validate the Spanish Low Vision Qualify of Life (SLVQOL) questionnaire, a quality of life instrument specifically designed for patients with visual impairment, and evaluate its psychometric properties.
The study included 170 visually impaired patients and 195 healthy subjects. Participants were administered the SLVQOL, the NEI VFQ-25, and the EQ 5D-5L questionnaires. Reliability, test-retest reproducibility, feasibility, and construct validity of the SLVQOL were assessed. The Generalized Partial Credit Model was used to fit the data and the performance of each item was characterized using category response curves and item information.
The reliability of the SLVQOL was 0.981 (95% CI: 0.978-0.985). Test-retest reproducibility was good (ρ=0.864, P<.001). A cut-off point of 105 or 106 was optimal to detect visual impairment, with a sensitivity of 95.4% and a specificity of 91.8%. Construct validity was shown by the corresponding convergence or divergence correlations between the score of the SLVQOL and its dimensions and the overall and partial scores of the NEI VFQ-25 and the EQ 5D-5L. Item response theory analysis showed discrimination and information parameters ranging from 0.539 to 3.063 and from -1.894 to 1.074, respectively.
The SLVQOL was able to quantitatively assess and identify differences in the quality of life among patients with visual impairment and normal subjects. The evaluated psychometric properties suggest that this tool has excellent validity, internal consistency, and reproducibility, but may benefit from a reduction of the number of items.
验证专门为视力障碍患者设计的生活质量工具——西班牙语低视力生活质量问卷（SLVQOL），评估其心理测量学特性。
本研究纳入了 170 名视力障碍患者和 195 名健康对照者。参与者完成了 SLVQOL、NEI VFQ-25 和 EQ 5D-5L 问卷。评估了 SLVQOL 的信度、重测信度、可行性和结构效度。使用广义部分信用模型对数据进行拟合，并用类别反应曲线和项目信息来描述每个项目的表现。
SLVQOL 的信度为 0.981（95%CI：0.978-0.985）。重测信度良好（ρ=0.864，P<.001）。105 或 106 分作为区分有无视力障碍的最佳截断值，灵敏度为 95.4%，特异度为 91.8%。SLVQOL 的评分与其维度以及 NEI VFQ-25 和 EQ 5D-5L 的总体和部分评分之间的相应收敛或发散相关性表明了结构效度。项目反应理论分析显示，辨别力和信息量参数范围分别为 0.539 至 3.063 和-1.894 至 1.074。
SLVQOL 能够定量评估和识别视力障碍患者和正常受试者之间的生活质量差异。评估的心理测量学特性表明，该工具具有极好的有效性、内部一致性和可重复性，但可能受益于项目数量的减少。
