McLachlan M S, Thomson J G, Taylor D W, Kelly M E, Sackett D L
AJR Am J Roentgenol. 1979 Feb;132(2):227-9. doi: 10.2214/ajr.132.2.227.
After agreeing on diagnostic criteria and after a pilot study, two experienced radiologists twice independently reviewed 40 lower limb venograms performed by a standard technique in patients suspected or known to have venous thrombosis. The observers reviewed 20 examinations at a time, their analysis requiring separate identification of 11 major veins. At each site observers stated whether thrombus was "absent," "doubtful," "presumed," or "definite," or declared "no opinion possible." They then rediscussed criteria of diagnosis and, using the same experimental design, examined another 40 venograms. To correct for agreement expected by chance, data were analyzed by using the kappa statistic. In general, levels of agreement were higher than those reported for many other clinical and radiologic investigations, probably because of refinement of criteria after the pilot study. Nonetheless, observers disagreed about the probable presence or absence of thrombus at some site in the limb in about 10% of examinations. Observer variation should be considered when venography is used as a reference standard to evaluate other methods of diagnosing thrombi.
在确定诊断标准并进行初步研究后，两名经验丰富的放射科医生两次独立审查了40例采用标准技术对疑似或已知患有静脉血栓形成的患者进行的下肢静脉造影。观察者每次审查20份检查，他们的分析需要分别识别11条主要静脉。在每个部位，观察者需说明血栓是“不存在”、“可疑”、“可能存在”还是“确定存在”，或者声明“无法给出意见”。然后他们重新讨论诊断标准，并采用相同的实验设计，审查另外40份静脉造影。为校正偶然因素导致的一致性，使用kappa统计量对数据进行分析。总体而言，一致性水平高于许多其他临床和放射学研究报告的水平，这可能是因为初步研究后标准得到了完善。尽管如此，在约10%的检查中，观察者对于肢体某些部位血栓可能存在或不存在的情况存在分歧。当静脉造影用作评估其他血栓诊断方法的参考标准时，应考虑观察者间差异。
