Determination of the minimal important difference for Dyspnoea-12 questionnaire in patients with COPD, after pulmonary rehabilitation.

INTRODUCTION: The authors of the international task force about the management of Dyspnoea recommend assessing sensory and affective components of dyspnoea. The Dyspnoea-12 questionnaire (D-12) allows to assess both components of dyspnoea. D-12 is valid and reliable but its sensitivity to pulmonary rehabilitation was not studied. The aim of this study was to estimate the minimal important difference (MID) for D-12 in COPD patients undergoing a pulmonary rehabilitation programme (PRP). METHODS: Severe or very severe COPD patients undergoing a PRP were included. Dyspnoea was assessed using D-12, MMRC dyspnoea scale, London chest of Activity of Daily Living questionnaire (LCADL). Quality of life was assessed using Saint-George respiratory questionnaire (SGRQ) and COPD assessment Test (CAT); exercise capacity using 6-Minute walk Test (6MWT) and 1-minute sit to-stand test (1STST). The MID was evaluated using distribution and anchor-based methods. RESULTS: Sixty patients (age: 64.4 ± 8.2; FEV1 (%): 28.6 ± 8.1) were included. At the end of the PRP, patients had significantly decreased their dyspnoea measured with D-12, MMRC, LCADL (D-12:23.9 ± 8.9 to 17.6 ± 9.4; MMRC: 3 ± 0.7 to 2.2 ± 1.1, LCADL: 38 ± 13.9 to 31.6 ± 11; p < 0.0001). Using the distribution-based analysis, MID of -2.67 (standard error of measurement) or -4.45 (standard deviation) was found. According to methodology, we could only use SGRQ as anchor. With SGRQ as anchor, the receiver operating characteristic curve identified MID for the change in D-12 at -6.1 (sensibility: 58%, specificity: 79%). The correlation with SGRQ was modest (r = 0.33), so the calculated MID should be interpreted with caution. CONCLUSION: D-12 is a good tool to assess the decrease of dyspnoea after PR. We propose MID of -6 points. However, Future estimates of MID for the D-12 should use anchors that are more strongly correlated with it.

[Manual airway clearance techniques in adults and adolescents: What level of evidence?] / Techniques manuelles de drainage bronchique des adultes et adolescents : quel niveau de preuve ?

BACKGROUND: The aim of this systematic literature review was to grade the levels of evidence of the most widely used manual airway clearance techniques. METHODS: A literature search was conducted over the period 1995-2014 from the Medline, PEDro, ScienceDirect, Cochrane Library, REEDOC and kinedoc databases, with the following keywords: "postural drainage", "manual vibrations", "manual chest percussion", "directed cough", "increased expiratory flow", "ELTGOL", "autogenic drainage" and "active cycle of breathing technique". RESULTS: Two-hundred and fifty-six articles were identified. After removing duplicates and reading the titles and abstracts, 63 articles were selected, including 9 systematic reviews. This work highlights the lack of useful scientific data and the difficulty of determining levels of evidence for manual airway clearance techniques. Techniques were assessed principally with patients with sputum production (cystic fibrosis, DDB, COPD, etc.). It also shows the limited pertinence of outcome measures to quantify congestion and hence the efficacy of airway clearance techniques. CONCLUSION: The 1994 consensus conference summary table classifying airway clearance techniques according to physical mechanism provides an interesting tool for assessment, grouping together techniques having identical mechanisms of action. From the findings of the present systematic review, it appears that only ELTGOL, autogenic drainage and ACBT present levels of evidence "B". All other techniques have lower levels of evidence. LEVEL OF EVIDENCE: II.