From the Departments of Pediatrics and Radiology, Division of Rheumatology, and Center for Pediatric Clinical Effectiveness (CPCE) at the Children's Hospital of Philadelphia; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Medicine at the University of Alberta; Department of Radiology and Diagnostic Imaging, University of Alberta; Canadian Research and Education (CaRE) Arthritis Organization, Edmonton, Alberta, Canada.
P.F. Weiss, MD, MSCE, Department of Pediatrics, Division of Rheumatology at the Children's Hospital of Philadelphia and Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania; W.P. Maksymowych, MD, FRCP, Department of Medicine at the University of Alberta; R.G. Lambert, MB BCh, FRCR, FRCPC, Department of Radiology and Diagnostic Imaging at the University of Alberta; J.L. Jaremko, MD, PhD, Department of Radiology and Diagnostic Imaging at the University of Alberta; D.M. Biko, MD, Department of Radiology at the Children's Hospital of Philadelphia; J. Paschke, BSc, CaRE Arthritis; T.G. Brandon, MPH, Department of Pediatrics, Division of Rheumatology at the Children's Hospital of Philadelphia; R. Xiao, PhD, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania; Department of Radiology and Diagnostic Imaging, University of Alberta; N.A. Chauvin, MD, Department of Radiology at the Children's Hospital of Philadelphia.
J Rheumatol. 2018 Oct;45(10):1411-1417. doi: 10.3899/jrheum.171329. Epub 2018 Jun 15.
There is a critical need for measures to evaluate structural progression in the pediatric sacroiliac joint (SIJ). We aimed to evaluate the construct validity and reliability of the Spondyloarthritis Research Consortium of Canada SIJ Structural Score (SSS) in children with suspected or confirmed juvenile spondyloarthritis.
The SSS assesses structural lesions of the SIJ on magnetic resonance imaging (MRI) through the cartilaginous part of the joint. We conducted 3 sequential reading exercises with 6 readers (1 adult and 3 pediatric radiologists, 1 adult and 1 pediatric rheumatologist). Each exercise was preceded by a calibration module. Interobserver reliability was assessed using intraclass correlation coefficients (ICC). Prespecified acceptable reliability thresholds were ICC > 0.5 for erosion, backfill, and sclerosis, and ICC > 0.7 for ankylosis and fat metaplasia.
The SSS had face validity and was feasible to score in pediatric cases for all 3 reading exercises. Of the cases used in the 3 exercises, 58% were male and the median age was 14 years (range 6.8-18.7 yrs). After calibration, median ICC across all readers for each SSS component were the following: erosion 0.67 (interquartile range 0.54-0.80), backfill 0.33 (0.19-0.52), fat metaplasia 0.74 (0.62-0.85), sclerosis 0.63 (0.48-0.77), and ankylosis 0.44 (0.28-0.62). Prespecified reliability thresholds were achieved in the third exercise for erosion, sclerosis, and fat metaplasia but not for backfill or ankylosis.
The SSS was feasible to score and had acceptable reliability for pediatric SIJ MRI evaluation. The ICC improved with additional calibration and reading exercises, even for readers with limited experience.
评估儿童骶髂关节（SIJ）结构进展的方法至关重要。我们旨在评估疑似或确诊幼年特发性脊柱关节炎患儿的加拿大脊柱关节炎研究协会骶髂关节结构评分（SSS）的构建效度和可靠性。
SSS 通过关节软骨部分评估磁共振成像（MRI）上的 SIJ 结构病变。我们进行了 3 次连续的阅读练习，共有 6 名读者（1 名成人和 3 名儿科放射科医生，1 名成人和 1 名儿科风湿病医生）参与。每次阅读练习前都有一个校准模块。使用组内相关系数（ICC）评估观察者间的可靠性。预定的可接受可靠性阈值为 ICC > 0.5 用于侵蚀、填充和硬化，ICC > 0.7 用于强直和脂肪化生。
SSS 具有表面效度，在所有 3 次阅读练习中均能对儿科病例进行评分。在用于 3 次练习的病例中，58%为男性，中位年龄为 14 岁（范围 6.8-18.7 岁）。经过校准，所有读者的 SSS 各组成部分的中位数 ICC 如下：侵蚀 0.67（四分位距 0.54-0.80）、填充 0.33（0.19-0.52）、脂肪化生 0.74（0.62-0.85）、硬化 0.63（0.48-0.77）和强直 0.44（0.28-0.62）。在第三次练习中，侵蚀、硬化和脂肪化生达到了预定的可靠性阈值，但填充和强直没有达到。
SSS 评分可行，具有可接受的儿童 SIJ MRI 评估可靠性。即使对于经验有限的读者，ICC 也随着额外的校准和阅读练习而提高。
