Páez A, Coba J M, Murillo N, Fernández P, de la Cal M A, Luján M, Berenguer A
Department of Urology, Hospital Universitario de Getafe, Madrid, Spain.
Eur Urol. 1999;35(3):228-32. doi: 10.1159/000019851.
To establish the reliability of three cytopathologists for cytological diagnosis of primary bladder tumors.
Preoperative voided urine specimens of 71 patients with bladder cancer and 55 noncancer controls were retrospectively and blindly reviewed by 3 independent cytologists, and their results compared. The estimation of the interobserver agreement was calculated using the weighted kappa coefficient. A multivariate analysis was carried out to identify the factors associated with the disagreement between the three observers. The sensitivity and specificity for each of the participants was calculated in order to clearly identify the origin of the disagreement, in terms of the performance of the diagnostic test in the hands of each observer. A comparison of the overall diagnostic performance was made by plotting sensitivity versus 1-specificity.
The weighted kappa coefficient among the 3 observers was 0.46. The multivariate analysis did not identify any variable that could have caused such disagreement. Vast differences in sensitivity and specificity were detected between observer 1 (sens. 0.90, spec. 0.45) and observers 2 (sens. 0.67, spec. 0.72) and 3 (sens. 0.71, spec. 0.80), but the overall diagnostic performance (sensitivity vs. 1-specificity) was superimposable in the 3 cases (p = NS).
Simple, reproducible and agreed-on-diagnostic criteria should be established to yield reliable results in a group of cytologists. The consideration of individual diagnostic performances can give a false idea of homogeneity between observers. In this field, concordance analysis makes quality control reliable and should be a routine procedure of any pathology department.
确定三位细胞病理学家对原发性膀胱肿瘤进行细胞学诊断的可靠性。
回顾性地、盲法审查71例膀胱癌患者和55例非癌对照者的术前排尿尿液标本，由3名独立的细胞学家进行评估，并比较他们的结果。使用加权kappa系数计算观察者间一致性的估计值。进行多变量分析以确定与三位观察者之间分歧相关的因素。计算每位参与者的敏感性和特异性，以便根据每位观察者手中诊断试验的表现明确分歧的来源。通过绘制敏感性与1-特异性的关系图对总体诊断性能进行比较。
三位观察者之间的加权kappa系数为0.46。多变量分析未发现任何可能导致这种分歧的变量。在观察者1（敏感性0.90，特异性0.45）与观察者2（敏感性0.67，特异性0.72）和观察者3（敏感性0.71，特异性0.80）之间检测到敏感性和特异性存在巨大差异，但在这3例中总体诊断性能（敏感性与1-特异性）是重叠的（p =无显著性差异）。
应建立简单、可重复且公认的诊断标准，以便在一组细胞学家中获得可靠的结果。考虑个体诊断性能可能会对观察者之间的同质性产生错误认识。在该领域，一致性分析使质量控制可靠，应成为任何病理科的常规程序。
