Análise das propriedades psicométricas do quality of life questionnaire bronchiectasis (QoL-B) para uso em pacientes com bronquiectasia não-fibrocística no Brasil

Abstract

Introduction: There is a considerable reduction in health-related quality of life (HRQoL) in individuals with bronchiectasis. The Quality of Life Questionnaire - Bronchiectasis (QoL-B), is a patient-reported outcome measure specific for bronchiectasis. Objectives: To test the psychometric properties of the Brazilian Portuguese version of QoL-B in individuals with bronchiectasis and to secondarily correlate their scores with the modified Medical Research Council dyspnea scale (mMRC) and the distance in the incremental shuttle walking test (ISWT). Method: Cross-sectional study with adults subjects with clinically stable bronchiectasis. They performed the spirometry, ISWT, mMRC dyspnea scale, and answered the HRQoL: Saint George's Respiratory Questionnaire (SGRQ) and QoL-B (version Bp-V3.1). Psychometric analyzes included internal consistency, test-retest reliability, concurrent and convergent validity, and interpretability. Results: One hundred and eight individuals were evaluated (mean age 48 ± 14 yrs), 61 (57%) women. Internal consistency was adequate on most scales (Cronbach's alpha ≥ 0.70). Test-retest coefficients were substantial (intraclass correlations r= 0.58 – 0.93). The standard error of measurement presented was good. Concurrent validity of QoL-B with SGRQ scores and convergent validity with mMRC and ISWT were moderate in most domains. No floor effect was observed. The ceiling effect was present only in the social and treatment burden domains. Conclusion: QoL-B is reliable, valid and has adequate internal consistency to assess the impact of bronchiectasis on the quality of life of Brazilian adults.