Anderson Wayne H, Ha Jae Wook, Couper David J, O'Neal Wanda K, Barr R Graham, Bleecker Eugene R, Carretta Elizabeth E, Cooper Christopher B, Doerschuk Claire M, Drummond M Bradley, Han MeiLan K, Hansel Nadia N, Kim Victor, Kleerup Eric C, Martinez Fernando J, Rennard Stephen I, Tashkin Donald, Woodruff Prescott G, Paine Robert, Curtis Jeffrey L, Kanner Richard E
Pulmonary and Critical Care Medicine, Department of Medicine, Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina United States of America.
Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
PLoS One. 2017 Sep 21;12(9):e0184606. doi: 10.1371/journal.pone.0184606. eCollection 2017.
Understanding the reliability and repeatability of clinical measurements used in the diagnosis, treatment and monitoring of disease progression is of critical importance across all disciplines of clinical practice and in clinical trials to assess therapeutic efficacy and safety.
Our goal is to understand normal variability for assessing true changes in health status and to more accurately utilize this data to differentiate disease characteristics and outcomes.
Our study is the first study designed entirely to establish the repeatability of a large number of instruments utilized for the clinical assessment of COPD in the same subjects over the same period. We utilized SPIROMICS participants (n = 98) that returned to their clinical center within 6 weeks of their baseline visit to repeat complete baseline assessments. Demographics, spirometry, questionnaires, complete blood cell counts (CBC), medical history, and emphysema status by computerized tomography (CT) imaging were obtained.
Pulmonary function tests (PFTs) were highly repeatable (ICC's >0.9) but the 6 minute walk (6MW) was less so (ICC = 0.79). Among questionnaires, the Saint George's Respiratory Questionnaire (SGRQ) was most repeatable. Self-reported clinical features, such as exacerbation history, and features of chronic bronchitis, often produced kappa values <0.6. Reported age at starting smoking and average number of cigarettes smoked were modestly repeatable (kappa = 0.76 and 0.79). Complete blood counts (CBC) variables produced intraclass correlation coefficients (ICC) values between 0.6 and 0.8.
PFTs were highly repeatable, while subjective measures and subject recall were more variable. Analyses using features with poor repeatability could lead to misclassification and outcome errors. Hence, care should be taken when interpreting change in clinical features based on measures with low repeatability. Efforts to improve repeatability of key clinical features such as exacerbation history and chronic bronchitis are warranted.
了解用于疾病诊断、治疗和监测疾病进展的临床测量的可靠性和可重复性，在所有临床实践学科以及评估治疗效果和安全性的临床试验中都至关重要。
我们的目标是了解用于评估健康状况真实变化的正常变异性，并更准确地利用这些数据来区分疾病特征和结果。
我们的研究是第一项完全旨在确定同一时期同一受试者用于慢性阻塞性肺疾病（COPD）临床评估的大量仪器的可重复性的研究。我们利用了SPIROMICS研究的参与者（n = 98），他们在基线访视后6周内返回临床中心，重复进行完整的基线评估。获取了人口统计学数据、肺功能测定、问卷、全血细胞计数（CBC）、病史以及通过计算机断层扫描（CT）成像得出的肺气肿状况。
肺功能测试（PFTs）具有高度可重复性（组内相关系数>0.9），但6分钟步行试验（6MW）的可重复性较差（ICC = 0.79）。在问卷中，圣乔治呼吸问卷（SGRQ）的可重复性最高。自我报告的临床特征，如加重病史和慢性支气管炎特征，其kappa值通常<0.6。报告的开始吸烟年龄和平均吸烟量的可重复性一般（kappa = 0.76和0.79）。全血细胞计数（CBC）变量的组内相关系数（ICC）值在0.6至0.8之间。
肺功能测试具有高度可重复性，而主观测量和受试者回忆的变异性更大。使用可重复性差的特征进行分析可能会导致错误分类和结果误差。因此，在基于可重复性低的测量来解释临床特征变化时应谨慎。有必要努力提高关键临床特征（如加重病史和慢性支气管炎）的可重复性。
