Department of Rheumatology, Ghent University Hospital, 0K12-IB, De Pintelaan 185, Ghent B-9000, Belgium.
Ann Rheum Dis. 2010 Jun;69(6):1092-6. doi: 10.1136/ard.2009.115568. Epub 2010 May 3.
Investigation of the reliability of the qualitative and semiquantitative scoring of nailfold videocapillaroscopy (NVC) assessment between two raters in a systemic sclerosis (SSc) cohort.
Two raters from different centres blindly assessed the NVC images of 71 consecutive patients with SSc qualitatively as belonging to the scleroderma spectrum (SDS) category ('early', 'active', 'late' scleroderma pattern or 'scleroderma-like' pattern) or to the 'normal' category and semiquantitatively by calculating the mean score for capillary loss, giant capillaries, microhaemorrhages and capillary ramifications. Inter-rater/intrarater agreement was assessed by calculation of the proportion of agreement and by kappa coefficients. Rater agreement of mean score values of hallmark parameters was assessed by intraclass correlation coefficients.
The inter-rater/intrarater proportion of agreement to qualitatively assess an image as belonging to the SDS category or not was 90% and 96%, whereas the agreement to distinguish between only 'early', 'active' and 'late' scleroderma NVC patterns was 62% and 81%. The agreement of the semiquantitative scoring, as assessed by intraclass correlation coefficient, was 0.96 and 0.95 for capillary loss, 0.84 and 0.95 for giant capillaries, 0.90 and 0.95 for microhaemorrhages and 0.64 and 0.95 for capillary ramifications.
This is the first study to demonstrate reliability of the qualitative and semiquantitative NVC assessment in an SSc cohort between raters at different centres. Reliability of NVC assessment is essential for use of this tool in multicentre SSc trials.
调查在系统性硬化症（SSc）队列中，两名评分者之间对甲褶毛细血管镜（NVC）评估的定性和半定量评分的可靠性。
两名来自不同中心的评分者对 71 例连续 SSc 患者的 NVC 图像进行盲法评估，将其定性为属于硬皮病谱（SDS）类别（“早期”、“活动期”、“晚期”硬皮病模式或“硬皮病样”模式）或“正常”类别，并通过计算毛细血管缺失、巨毛细血管、微出血和毛细血管分支的平均评分进行半定量评估。通过计算一致性比例和kappa 系数评估组内/组间一致性。通过组内相关系数评估主要参数平均评分值的评分者一致性。
定性评估图像是否属于 SDS 类别的组内/组间一致性比例为 90%和 96%，而区分“早期”、“活动期”和“晚期”硬皮病 NVC 模式的一致性比例为 62%和 81%。通过组内相关系数评估的半定量评分一致性为毛细血管缺失 0.96 和 0.95，巨毛细血管 0.84 和 0.95，微出血 0.90 和 0.95，毛细血管分支 0.64 和 0.95。
这是第一项在不同中心的评分者之间对 SSc 队列中的 NVC 定性和半定量评估进行可靠性研究。NVC 评估的可靠性对于在多中心 SSc 试验中使用该工具至关重要。
