白内障患者报告结局条目库的研制

目的:基于Rasch模型研制白内障患者报告结局(PROs)条目库,为准确、全面和动态评估白内障PROs奠定基础.方法:横断面调查研究.根据纳入标准选取我院已确诊的白内障住院患者,采用本课题组前期基于循证医学方法构建的白内障PROs条目池对其进行问卷调查.通过Rasch分析各维度条目选项概率曲线(CPC)、测量精密性、条目拟合指标(infit/outfit MNSQ)、单维性、匹配度和条目功能差异(DIF)等测量特性指标,并反复迭代、提炼,直至得到测量特性优良的条目.采用Pearson相关分析评估各维度和视力的相关性.结果:共纳入296例白内障患者,其中男130例,女166例,年龄70(63,77)岁,受过小学及以上教育者178例(60.1%),术前双眼日常生活视力(LogMAR)为0.0~3.0,中位数为0.6.条目库共纳入3个维度,其中视觉相关活动受限维度23个条目,视觉症状维度14个条目,精神心理健康11个条目,所有条目选项数量均为4个.视觉相关活动受限维度中,选项类别阈值分别为-1.84、0.04、1.79,被试分离信度/被试分离系数(PSR/PSI)为0.93/3.59,主成分分析(PCA)第一成分未解释方差特征值为2.61,匹配度为-0.81,DIF值均小于1;该维度得分与好眼视力(r=0.619,P<0.01)和双眼视力(r=0.622,P<0.01)有相关性.视觉症状维度中,选项类别阈值分别为-1.83、-0.18、2.00,PSR/PSI为0.88/2.68,PCA第一成分未解释方差特征值为2.53,匹配度为-1.35,2个条目在眼部并发症方面的DIF值大于1,其余DIF值均小于1;该维度得分与好眼视力(r=0.482,P<0.01)和双眼视力(r=0.492,P<0.01)有相关性.精神心理健康维度中,选项类别阈值分别为-2.83、0.03、2.80,PSR/PSI为0.88/2.68,PCA第一成分未解释方差特征值为2.79,匹配度为-0.34,所有条目DIF值均小于1;该维度得分与好眼视力(r=0.425,P<0.01)和双眼视力(r=0.426,P<0.01)有相关性.上述所有条目infit和outfit值均介于0.50~1.50之间.结论:基于Rasch分析研制的白内障PROs条目库覆盖了视觉相关活动受限、视觉症状和精神心理健康3个方面,全面地反应了白内障PROs的内涵,且条目简明易懂,临床可操作性好,具有较好的测量特性.

The Development of a Cataract-specific Item Bank to Measure Patient-reported Outcomes

Objective: To develop a Rasch-based item bank for the assessment of Cataract-specific patient-reported outcomes (PROs) that can be evaluated precisely, comprehensively and dynamically. Methods: In this cross-sectional study, patients diagnosed with cataract in the Eye Hospital of Wenzhou Medical University were enrolled. Cataract patients answered an item pool of cataract PROs that was established by following the guidelines of the international PRO development process. Rasch analysis was used to test the category probability curve (CPC), measure precision, infit/outfit MNSQ, unidimensionality, targeting and differential item functioning (DIF). The items were refined until reliable characteristics were developed for the item bank. A Pearson correlation analysis was used to test each dimension for its correlation with visual acuity. Results: A total of 296 patients (130 males) were recruited for this study. Of those, 60.1% were illiterate with a median age of 70 years, an interquartile range of 63 to 77 years, and a preoperative binocular visual acuity (LogMAR) range from 0.0 to 3.0 (median 0.6). The conceptual framework of the item bank consisted of three domains. The Rasch analysis led to the following item banks: "Vision-related activity limitation" (23 items), "Visual symptoms" (14 items) and "Emotional well-being" (11 items). All items had four response options. The vision-related activity limitation domain had a category threshold order of -1.84, 0.04, 1.79, a person separation reliability/person separation index (PSR/PSI) of 0.93/3.59, an eigenvalue of principal component analysis of 2.61, and targeting of -0.81 none of the items had a DIF. This domain had a moderate correlation with better visual acuity (r=0.619, P<0.01) and binocular visual acuity (r=0.622, P<0.01). The vision symptoms domain had a category threshold order of -1.83, -0.18, 2.00, a PSR/PSI of 0.88/2.68, an eigenvalue of principal components analysis of 2.53, and targeting of -1.35. Two items showing a DIF of ocular comorbidities. This domain had a moderate correlation with better visual acuity (r=0.482, P<0.01) and binocular visual acuity (r=0.492, P<0.01). The emotional well-being domain had a category threshold order of -2.83, 0.03, 2.80, a PSR/PSI of 0.88/2.68, an eigenvalue of principal components analysis of 2.79, targeting of -0.34. None of the items had a DIF. This domain showed moderate correlation with better visual acuity (r=0.425, P<0.01) and binocular visual acuity (r=0.426, P<0.01). All items were trimmed to meet the goodness of fit statistic criteria of 0.50-1.50. Conclusions: This study, which is based on the Rasch analysis, developed a cataract item bank that covers all three common concern domains of cataract patients. It is a comprehensive assessment denoting the PROs of cataract patients and is easy to understand and administer. It not only shows perfect psychometric properties but is also appropriate for measuring PROs in Chinese cataract patients.