The Clinical COPD Questionnaire: response to pulmonary rehabilitation and minimal clinically important difference

Abstract

BackgroundThe Clinical COPD Questionnaire (CCQ) is a simple 10-item, health-related quality of life questionnaire (HRQoL) with good psychometric properties. However, little data exists regarding the responsiveness of the CCQ to pulmonary rehabilitation (PR) or the minimal clinically important difference (MCID). The study aims were to assess the responsiveness of the CCQ to PR, to compare the responsiveness of the CCQ to other HRQoL questionnaires and to provide estimates for the MCID. Methods The CCQ, St George's Respiratory Questionnaire (SGRQ), Chronic Respiratory Questionnaire (CRQ) and COPD Assessment Test (CAT) were measured in 261 patients with COPD before and after outpatient PR. Pre to post PR changes and Cohen's effect size were calculated. Changes in CCQ were compared with changes in other HRQoL questionnaires. Using an anchor-based approach and receiver operating characteristic (ROC) curves, the CCQ change cutoffs that identified patients achieving the known MCID for other health status questionnaires with PR were identified. Results The CCQ, SGRQ, CRQ and CAT all significantly improved with PR with an effect size of −0.39, −0.33, 0.62 and −0.25, respectively. CCQ change correlated significantly with change in SGRQ, CRQ and CAT (r=0.48, 0.54, respectively; all p<0.001). ROC curves consistently identified a CCQ change cutoff of −0.4 as the best discriminating value to identify the MCID for the SGRQ, CRQ and CAT (area under curve: 0.71, 0.75 and 0.77, respectively; all p<0.001). Conclusions The CCQ is responsive to PR with an estimated clinically important improvement of −0.4 points. The CCQ is a practical alternative to more timeconsuming measures of HRQoL.

Health status instruments for patients with COPD in pulmonary rehabilitation: defining a minimal clinically important difference

“…Questionnaire-referencing resulted in ranges of 0.28–0.60 (SGRQ anchor) and 0.42–0.61 (CAT anchor), which to some extent matched the results of Kon et al . 17 for COPD, as well as of Canavan et al for other respiratory diseases. 18 With regard to the distribution-based methods, the 1.96SEM and 0.5s.d.…”

Estimation of Minimal Clinically Important Difference in EQ-5D Visual Analog Scale Score After Pulmonary Rehabilitation in Subjects With COPD

“…However, up to now, there has been no consensus on the optimal method to estimate the MCID. 42,43 Furthermore, the ROC curve method, using external anchor measures, was successfully used to calculate the MCID of the Clinical COPD Questionnaire 44 and of the 5-repetition sit-to-stand test 45 in subjects with COPD. We acknowledge that the lack of control group may be a limitation of our study.…”

Patient Satisfaction and Clinical Outcomes with Budesonide plus Formoterol Spiromax for Asthma and Chronic Obstructive Pulmonary Disease: A Real-World, Observational Trial

“…Patient-reported control of symptoms improved during the study, based on the ACT and CAT questionnaires that were previously validated in relevant clinical populations [28, 29]. Patients with COPD, in particular, showed a marked and significant improvement between baseline and week 12 in all symptoms assessed in the CAT, achieving more than double the minimal clinically important difference [30]. …”