Validation of the French version of the Leicester Cough Questionnaire in chronic obstructive pulmonary disease.

Cough is one of the three major symptoms reported by chronic obstructive pulmonary disease (COPD) patients. The Leicester Cough Questionnaire (LCQ) is a questionnaire exploring the impact of cough, but it does not exist in French. The aim of this study was to develop a French version of LCQ and to assess its psychometrics properties. A forward-backward translation process was used to develop the French version of the LCQ. COPD patients completed LCQ and Cough and Sputum Assessment Questionnaire (CASA-Q) to determine concurrent validity, content validity and internal consistency. Two weeks later, the LCQ was repeated to evaluate the reproducibility. Seventy-four COPD patients were recruited. The concurrent validity showed highly significant correlations between all scores of LCQ and CASA-Q (p < 0.001). The content validity was good with domain total scores correlations ranging from 0.918 to 0.953. The LCQ domains and total scores showed a very good internal consistency with Cronbach's α coefficients ranging between 0.802 and 0.917. The test-retest reliability was high in COPD patients with no change in cough. In conclusion, The French version of the LCQ is a valid and reliable instrument to measure health status in COPD patients.