Centre for Eye Research Australia, the Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, VIC, Australia.
Invest Ophthalmol Vis Sci. 2010 Jun;51(6):2878-84. doi: 10.1167/iovs.09-4494. Epub 2010 Jan 20.
To determine the psychometric validity of the National Eye Institute-Visual Function Questionnaire (NEI VFQ-25) and its subscale structure for use in people with low vision.
Two hundred thirty-two participants completed the NEI VFQ-25. Rasch analysis was used to test the psychometric performance of the questionnaire and each subscale. Factor models were hypothesized and tested with confirmatory factor analysis (CFA) and subsequently validated with Rasch analysis.
For the overall scale, two rating scales had to be dichotomized and three misfitting items removed to improve fit to the Rasch model. There was evidence of multidimensionality, indicating that the scale would benefit from scale splitting. For the NEI VFQ-25 subscale structure, six of the original 12 subscales could not fit the Rasch model because of item insufficiency (fewer than two items) and the remaining six displayed poor item fit characteristics indicating that the NEI VFQ-25 does not have a viable subscale structure. CFA supported a two-factor model with visual functioning (10 items) and socioemotional (9 items) scales. Most goodness-of-fit statistics were within the recommended range of values. The factor loadings of items on their respective scales were statistically significant (P < 0.001) and ranged between 0.59 and 0.84. The two scales individually fitted the Rasch model and were found to be unidimensional with adequate psychometric characteristics.
The native NEI VFQ-25 is a better performing instrument when split into visual functioning and socioemotional scales. These scales possess valid parameters for assessment of the impact of low vision in this population.
确定国家眼科研究所视觉功能问卷（NEI VFQ-25）及其分量表结构在低视力人群中的心理测量有效性。
232 名参与者完成了 NEI VFQ-25。使用 Rasch 分析测试问卷和每个分量表的心理测量性能。假设并通过验证性因子分析（CFA）测试因子模型，随后使用 Rasch 分析进行验证。
对于总体量表，需要将两个评分量表二分，并删除三个拟合不良的项目，以改善对 Rasch 模型的拟合。存在多维性的证据，表明该量表将受益于量表拆分。对于 NEI VFQ-25 分量表结构，由于项目不足（少于两个项目），原始 12 个分量表中的 6 个无法适应 Rasch 模型，而其余 6 个显示出较差的项目拟合特征，表明 NEI VFQ-25 没有可行的分量表结构。CFA 支持具有视觉功能（10 个项目）和社会情感（9 个项目）量表的两因素模型。大多数拟合优度统计数据在推荐值范围内。项目在各自量表上的因子负荷具有统计学意义（P <0.001），范围在 0.59 到 0.84 之间。两个量表单独适应 Rasch 模型，并且被发现具有一维性和足够的心理测量特征。
当 NEI VFQ-25 分为视觉功能和社会情感量表时，其表现更好。这些量表具有评估该人群低视力影响的有效参数。
