The development and validation of the King's Brief Interstitial Lung Disease (K-BILD) health status questionnaire. Issue 9 (3rd May 2012)

• Record Type: Journal Article
• Authors: Patel, Amit S; Siegert, Richard J; Brignall, Katherine; Gordon, Patrick; Steer, Sophia; Desai, Sujal R; Maher, Toby M; Renzoni, Elisabetta A; Wells, Athol U; Higginson, Irene J; Birring, Surinder S
• Is Part Of: Thorax. Volume 67:Issue 9(2012)
• Page Start: 804
• Page End: 810
• Publication Date: 2012-05-03
• Subjects: Quality of life -- interstitial lung disease -- idiopathic pulmonary fibrosis -- connective tissue disease -- NSIP -- health status -- interstitial fibrosis -- sarcoidosis -- non-invasive ventilation -- COPD mechanisms -- ANCA related vasculitides -- systemic disease and lungs -- lung transplantation -- α1 antitrypsin deficiency -- cystic fibrosis -- respiratory measurement -- lung physiology -- bronchiectasis -- airway epithelium -- drug-induced lung disease -- rare lung diseases -- allergic alveolitis -- ANCA-related vasculitides -- asbestos-induced lung disease -- pulmonary eosinophilia -- pulmonary vasculitis -- cough/mechanisms/pharmacology; Chest -- Diseases -- Periodicals; Thorax; Chest -- Diseases; Periodicals; Periodicals; 617.54
• DOI: 10.1136/thoraxjnl-2012-201581
• Languages: English
• ISSNs: 0040-6376

Abstract

Abstract : Rationale: Health status is impaired in patients with interstitial lung disease (ILD). There is a paucity of tools that assess health status in ILD. The objective of this study was to develop and validate the King's Brief Interstitial Lung Disease questionnaire (K-BILD), a new health status measure for patients with ILD. Methods: Patients with ILD were recruited from outpatient clinics. The development of the questionnaire consisted of three phases: item generation; item reduction, allocation to domains by factor analysis, Rasch analysis to create unidimensional scales and validation; and repeatability testing. Results: 173 patients with ILD (49 with idiopathic pulmonary fibrosis) completed a preliminary 71-item questionnaire. 56 items were removed due to redundancy, low factor loadings or poor fit to the Rasch model. The final version of the K-BILD questionnaire consisted of 15 items and three domains (breathlessness and activities, chest symptoms and psychological). Internal consistency assessed with Cronbach's α coefficient was 0.94 for the K-BILD total score. Concurrent validity of the K-BILD questionnaire was high compared with St George's Respiratory Questionnaire (r=0.90) and moderate with lung function (vital capacity, r=0.50). The K-BILD questionnaire was repeatable over 2 weeks (n=44), with intraclass correlation coefficients for domains and total score 0.86–0.94. The K-BILD construct validity for patients with idiopathic pulmonary fibrosis was similar to that of other ILDs. Conclusion: The K-BILD questionnaire is a brief, valid, self-completed health status measure for ILD. It could be used in the clinic to assess ILD from the patients' perspective.