National Health and Medical Research Council Centre for Clinical Eye Research, Flinders Medical Centre and Flinders University of South Australia, Bedford Park, South Australia, Australia.
Invest Ophthalmol Vis Sci. 2012 Oct 25;53(11):7370-4. doi: 10.1167/iovs.12-9969.
To assess the psychometric properties of the National Eye Institute Refractive Error Quality of Life (NEI-RQL-42) questionnaire in keratoconus and compare these findings to patients with refractive error correction alone.
The Portuguese version of the NEI-RQL-42 Quality of Life questionnaire was completed by 44 patients who had keratoconus before and after implantation of intracorneal ring segments. Rasch analysis was used to assess the use of response categories, success in measuring a single trait per subscale (unidimensionality), ability to discriminate person ability (precision), and targeting of questions to person quality of life (QoL).
Rasch analysis was performed for the questionnaire subscales using stacked preoperative and postoperative data. Three subscales (Symptoms, Dependence on correction, and Suboptimal correction) contained response categories that were not used as intended. Six subscales contained misfitting items indicating multidimensionality. Eleven subscales exhibited inadequate measurement precision. Only the Near vision subscale demonstrated adequate precision with a person separation greater than 2.0. Targeting of items to person QoL was adequate in 11 of the 12 subscales with a mean item location of less than 1 logit.
Only one NEI-RQL-42 subscale (Near vision) performed adequately in keratoconus. Targeting was better in patients with keratoconus than in patients with refractive error correction alone, but 11 of the 12 subscales remain manifestly inadequate. Better instruments exist for measuring patient-reported outcomes in keratoconus.
评估圆锥角膜患者使用国家眼科研究所屈光不正生活质量（NEI-RQL-42）问卷的心理测量特性，并将这些发现与仅接受屈光不正矫正的患者进行比较。
对 44 例接受角膜内环段植入术的圆锥角膜患者进行了 NEI-RQL-42 生活质量问卷的葡萄牙语版本的填写。使用 Rasch 分析评估了反应类别、每个子量表测量单一特征的成功程度（单维性）、区分个体能力的能力（精度）以及问题针对个体生活质量（QoL）的定位。
使用堆叠的术前和术后数据对问卷子量表进行了 Rasch 分析。三个子量表（症状、对矫正的依赖和矫正不足）包含未按预期使用的反应类别。六个子量表包含不适合的项目，表明存在多维性。十一个子量表显示出测量精度不足。只有近视力子量表具有足够的精度，个体分离大于 2.0。12 个子量表中的 11 个子量表的项目定位都足够，平均项目位置小于 1 对数。
只有一个 NEI-RQL-42 子量表（近视力）在圆锥角膜中表现良好。在圆锥角膜患者中的定位优于仅接受屈光不正矫正的患者，但 11 个子量表中的 11 个仍明显不足。有更好的工具可用于测量圆锥角膜患者的患者报告结局。
