Schneeweiss S
Harvard Medical School, USA.
Int J Technol Assess Health Care. 2000 Summer;16(3):834-41. doi: 10.1017/s0266462300102107.
The evaluation of the diagnostic value of endoscopic procedures usually lacks a gold standard when performed in cross-sectional studies. The objective is to demonstrate an easily applicable method to assess the possible range of sensitivity, specificity, and predictive values of endoscopic procedures in the absence of a gold standard method.
Data from a study of 328 endoscopies comparing two different methods to diagnose superficial bladder cancer were used as a numerical example. Both endoscopic procedures were performed in the same patients in one session. Under the assumption of a systematic misclassification process, a model to correct sensitivity estimates is developed.
The lowest possible sensitivity estimate for a new fluorescence endoscopy technique (FE) was 78%, the maximum 97.5%. Depending on realistic assumptions made upon the misclassification, a reasonable estimate for sensitivity was 93.4% (95% confidence interval [CI]: 90%-97.3%) for the FE technique. The sensitivity of the traditional white-light endoscopy method ranged from 47.2% to 53%, with a reasonable estimate of 46.7% (95% CI: 39.4%-54.3%).
This method to determine the theoretically possible range of sensitivity estimates in endoscopic procedures is helpful in cross-sectional studies with a missing gold standard method. It is easily applicable for a variety of endoscopic procedures, including upper and lower gastro-intestinal tract, urogenital tract, or diagnostic laparoscopic surgery.
在横断面研究中，内镜检查诊断价值的评估通常缺乏金标准。目的是证明一种易于应用的方法，用于在缺乏金标准方法的情况下评估内镜检查敏感性、特异性和预测值的可能范围。
一项对328例内镜检查进行研究的数据，该研究比较了两种诊断浅表性膀胱癌的不同方法，以此作为数值示例。两种内镜检查均在同一患者的同一时段进行。在系统错误分类过程的假设下，开发了一种校正敏感性估计值的模型。
一种新的荧光内镜技术（FE）的最低可能敏感性估计值为78%，最高为97.5%。根据对错误分类所做的实际假设，FE技术的敏感性合理估计值为93.4%（95%置信区间[CI]：90%-97.3%）。传统白光内镜检查方法的敏感性范围为47.2%至53%，合理估计值为46.7%（95%CI：39.4%-54.3%）。
这种确定内镜检查敏感性估计值理论上可能范围的方法，对于缺乏金标准方法的横断面研究很有帮助。它易于应用于各种内镜检查，包括上、下胃肠道、泌尿生殖道或诊断性腹腔镜手术。
