Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante, Alicante, Spain.
Departamento de Oftalmología, Optometría, Otorrinolaringología y Anatomía Patológica, Universidad de Murcia, Murcia, Spain.
Transl Vis Sci Technol. 2022 Feb 1;11(2):7. doi: 10.1167/tvst.11.2.7.
To assess psychometric properties of the Symptom Questionnaire for Visual Dysfunctions (SQVD) questionnaire, including accuracy, validity, and reliability, in a clinical sample of patients having any type of visual dysfunction.
A clinical sample of 306 patients self-administered the SQVD. Rasch analysis was performed to analyze the functionality of the response categories, fit statistics, differential item functioning (DIF), person and item reliability, targeting, local dependency, unidimensionality, and transformation table. Accuracy was assessed by means of receiver operating characteristic (ROC) curves, using symptoms reported in each patient's clinical record as the gold standard for classifying patients with and without symptoms. The concurrent validity, known group validity, and test-retest reliability (repeatability, using the intraclass correlation coefficient [ICC]) were also examined.
SQVD showed orderly category responses. The 14 items fit the Rasch model without significant DIF for gender, presbyopia, and dysfunctions. Person and item reliabilities were 0.81 and 0.85, respectively. Targeting was -1.49 logits. Yen's Q3 statistic showed no local dependency. SQVD was unidimensional (first contrast of the residual = 1.852 eigenvalue with a variance explained by measures of 52.23%). The area under the ROC curve was 0.836 (95% confidence interval [CI], 0.792-0.879) with a cutoff of ≥6 showing good accuracy (sensitivity = 0.759; specificity = 0.783). SQVD showed good concurrent and known group validity and high repeatability (ICC, 0.857; 95% CI, 0.710-0.933) when administered twice 1 week apart.
SQVD has shown good psychometric properties. It can be considered an accurate, valid, and reliable questionnaire to detect visual symptoms related to any type of refractive, accommodative, and binocular dysfunction.
SQVD may be used for diagnostic purposes, as it can accurately detect symptoms related to any sort of visual dysfunction. It may also be useful to monitor the treatment outcomes of these conditions.
评估视觉障碍症状问卷（SQVD）在任何类型视觉功能障碍患者的临床样本中的心理测量学特性，包括准确性、有效性和可靠性。
对 306 例患者进行了临床样本的 SQVD 自我评估。进行了 Rasch 分析，以分析响应类别、拟合统计、差异项目功能（DIF）、个体和项目可靠性、目标、局部依赖性、单维性和转换表的功能。通过使用每个患者临床记录中报告的症状作为分类有症状和无症状患者的金标准，评估准确性。还检查了同时有效性、已知组有效性和测试-重测可靠性（使用组内相关系数 [ICC] 进行重复性）。
SQVD 显示出有序的类别反应。14 个项目符合 Rasch 模型，性别、老视和功能障碍无显著 DIF。个体和项目可靠性分别为 0.81 和 0.85。目标值为-1.49 对数单位。Yen 的 Q3 统计显示无局部依赖性。SQVD 是单维的（残差的第一对比为 1.852 特征值，可解释的测量值为 52.23%）。ROC 曲线下面积为 0.836（95%置信区间 [CI]，0.792-0.879），截断值≥6 显示出良好的准确性（敏感性=0.759；特异性=0.783）。SQVD 在两次相隔 1 周的测试中表现出良好的同时和已知组有效性和高度可重复性（ICC，0.857；95%CI，0.710-0.933）。
SQVD 具有良好的心理测量学特性。它可以被认为是一种准确、有效和可靠的问卷，用于检测与任何类型的屈光、调节和双眼功能障碍相关的视觉症状。它也可能有助于监测这些疾病的治疗结果。
