Validation of the polish version of the chronic cough quality of life questionnaire (Leicester cough questionnaire)

Background. The Leicester Cough Questionnaire (LCQ) is one of the few specific quality-of-life questionnaires (QOLQ) dedicated to measuring the impact of chronic cough on patients' health/condition. Objectives. The aim of the study was to validate the Polish version of the LCQ. Material and Methods. The LCQ was translated forward and backward. The Polish version of the LCQ was tested on 35 patients suffering from chronic cough (23 women, median age 60 years, non- or ex-smokers, median cough duration of 23 weeks). Its validity was tested by comparison to a visual analogue scale (VAS) of cough intensity and other health questionnaires (hospital anxiety and depression scale - HADS, Euro-Quality of Life Questionnaire - EQ5D, St. George's Respiratory Questionnaire - SGRQ). The internal reliability of the Polish version of the LCQ was determined using the Cronbach alpha coefficient and its repeatability by the intraclass consistency coefficient. Results. The translation of the LCQ into Polish was accepted by the author of the original LCQ. The Cronbach's alpha coefficient for total LCQ was 0.89, and reached 0.82, 0.86 and 0.78 for the physical, psychological and social domain, respectively. There were significant negative correlations between cough severity measured by VAS, the results of the EQ5D and SGRQ and the Polish version of the LCQ. The intraclass correlation coefficient of the test-retest reliability was significant (0.99). Conclusions. The Polish version of the LCQ has been validated and is a reliable tool to measure the impact of chronic cough on quality of life of patients with chronic cough.