Validation of the Leicester Cough Questionnaire in Brazilian Portuguese.

Purpose: This study aimed to validate the Leicester Cough Questionnaire (LCQ) for Brazilian Portuguese.

Methods: Validation followed the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN). Data collection included a sociodemographic questionnaire, the translated version of LCQ-Brazil (LCQ-Br), self-perception of laryngeal sensitivity, cough frequency and intensity, the Cough Severity Index (CSI-Br), and the Newcastle Laryngeal Hypersensitivity Questionnaire (LHQ-Br). The LCQ-Br retained its original structure with 19 items across physical, psychological, and social domains. Participants completed the LCQ-Br on three occasions to assess validity, reliability, and responsiveness.

Results: Ninety-eight patients with chronic cough (79% women; mean age of 49) participated. Construct validation confirmed the LCQ-Br's factorial structure. For concurrent validity, negative correlations were observed between LCQ-Br domains and self-perceived laryngeal sensitivity, cough frequency and intensity, and CSI-Br factors (physical, social, psychological, and total scores). A positive correlation was found between the LCQ-Br total and LHQ-Br scores. Internal consistency was high (Cronbach's alpha = 0.952), and test-retest reliability yielded a coefficient of 0.455. The responsiveness analysis demonstrated significant reductions in LCQ-Br scores post-intervention for physical, psychological, and total domains.

Conclusion: The LCQ-Br is a valid, reliable, and responsive tool for assessing health status in chronic cough patients, making it suitable for clinical practice and research applications.