Back to Journals » International Journal of Chronic Obstructive Pulmonary Disease » Volume 11 » Issue 1

Investigating sensitivity, specificity, and area under the curve of the Clinical COPD Questionnaire, COPD Assessment Test, and Modified Medical Research Council scale according to GOLD using St George's Respiratory Questionnaire cutoff 25 (and 20) as reference

Authors Tsiligianni I, Alma H, de Jong C, Jelusic D, Wittmann M, Schuler M, Schultz K, Kollen B, van der Molen T, Kocks J

Received 3 November 2015

Accepted for publication 30 December 2015

Published 18 May 2016 Volume 2016:11(1) Pages 1045—1052

DOI https://doi.org/10.2147/COPD.S99793

Checked for plagiarism Yes

Review by Single-blind

Peer reviewers approved by Dr Glenda Ernst

Peer reviewer comments 2

Editor who approved publication: Dr Richard Russell


Ioanna G Tsiligianni,1,2 Harma J Alma,1,2 Corina de Jong,1,2 Danijel Jelusic,3 Michael Wittmann,3 Michael Schuler,4 Konrad Schultz,3 Boudewijn J Kollen,1 Thys van der Molen,1,2 Janwillem WH Kocks1,2

1Department of General Practice, 2GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands; 3Klinik Bad Reichenhall, Center for Rehabilitation, Pulmonology and Orthopedics, Bad Reichenhall, 4Department of Medical Psychology, Psychotherapy and Rehabilitation Sciences, University of Würzburg, Würzburg, Germany

Background: In the GOLD (Global initiative for chronic Obstructive Lung Disease) strategy document, the Clinical COPD Questionnaire (CCQ), COPD Assessment Test (CAT), or modified Medical Research Council (mMRC) scale are recommended for the assessment of symptoms using the cutoff points of CCQ ≥1, CAT ≥10, and mMRC scale ≥2 to indicate symptomatic patients. The current study investigates the criterion validity of the CCQ, CAT and mMRC scale based on a reference cutoff point of St George’s Respiratory Questionnaire (SGRQ) ≥25, as suggested by GOLD, following sensitivity and specificity analysis. In addition, areas under the curve (AUCs) of the CCQ, CAT, and mMRC scale were compared using two SGRQ cutoff points (≥25 and ≥20).
Materials and methods: Two data sets were used: study A, 238 patients from a pulmonary rehabilitation program; and study B, 101 patients from primary care. Receiver-operating characteristic (ROC) curves were used to assess the correspondence between the recommended cutoff points of the questionnaires.
Results: Sensitivity, specificity, and AUC scores for cutoff point SGRQ ≥25 were: study A, 0.99, 0.43, and 0.96 for CCQ ≥1, 0.92, 0.48, and 0.89 for CAT ≥10, and 0.68, 0.91, and 0.91 for mMRC ≥2; study B, 0.87, 0.77, and 0.9 for CCQ ≥1, 0.76, 0.73, and 0.82 for CAT ≥10, and 0.21, 1, and 0.81 for mMRC ≥2. Sensitivity, specificity, and AUC scores for cutoff point SGRQ ≥20 were: study A, 0.99, 0.73, and 0.99 for CCQ ≥1, 0.91, 0.73, and 0.94 for CAT ≥10, and 0.66, 0.95, and 0.94 for mMRC ≥2; study B, 0.8, 0.89, and 0.89 for CCQ ≥1, 0.69, 0.78, and 0.8 for CAT ≥10, and 0.18, 1, and 0.81 for mMRC ≥2.
Conclusion: Based on data from these two different samples, this study showed that the suggested cutoff point for the SGRQ (≥25) did not seem to correspond well with the established cutoff points of the CCQ or CAT scales, resulting in low specificity levels. The correspondence with the mMRC scale seemed satisfactory, though not optimal. The SGRQ threshold of ≥20 corresponded slightly better than SGRQ ≥25, recently suggested by GOLD 2015, with the established cutoff points for the CCQ, CAT, and mMRC scale.

Keywords:
pulmonary disease, chronic obstructive, health status

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]