Translation and linguistic validation of the bronchiectasis health questionnaire (BHQ) into Danish

Introduction: Patients with bronchiectasis suffer from breathlessness, cough and sputum production, which impairs quality of life. The Bronchiectasis Health Questionnaire (BHQ), a short and disease-specific questionnaire, has previously been developed and validated in English. The aim of this study was to translate and validate the BHQ in Danish, using established cross-cultural validation methods. Methods: To create a Danish version of the questionnaire, this study used linguistic validation, a pilot study in 17 patients and forward-backward translation. Thereafter, 111 patients with bronchiectasis were asked to complete the BHQ (BHQ1) as well as the St George Respiratory Questionnaire (SGRQ), and one in three patients were asked to repeat the BHQ after two weeks had passed (BHQ2). Results: There was a significant convergent validity between the BHQ1 and the SGRQ (ρ = –0,826, p = 0.0001), a satisfactory correlation coefficient between the BHQ1 and the BHQ2 (0.739) and a lower limit of agreement of –15.96 and 20.56 in the Bland Altmann plot. Conclusions: The BHQ is translated and validated in Danish and retains good validity properties. This questionnaire is ready for use in daily clinical practice among Danish-speaking patients.