Validation of a visual analogue score (LRTI-VAS) in non-CF bronchiectasis

Background and aim: Quality of life in patients with non-cystic fibrosis (non-CF) bronchiectasis is largely defined by respiratory symptoms. To date, no disease-specific tool for symptom measurement in this patient group was available. We developed the lower respiratory tract infections - visual analogue scale (LRTI-VAS) in order to quickly and conveniently quantify symptoms in non-CF bronchiectasis. This study aimed to validate LRTI-VAS for use in non-CF bronchiectasis.

Methods: This study included outpatients with radiologically proven bronchiectasis and no evidence of CF. Results of LRTI-VAS were compared with other markers of disease activity {lung function parameters, oxygen saturation and three health-related quality of life questionnaires [Medical Outcomes Study Short-Form 36 Health Survey (SF-36), St Georges Respiratory Questionnaire (SGRQ) and Leicester Cough Questionnaire (LCQ)]} and validity, reliability and responsiveness were assessed.

Results: Thirty stable and 30 exacerbating participants completed the LRTI-VAS questionnaire. When testing for repeatability on two separate occasions, no statistically significant difference between total scores was found {1.4 [standard deviation (SD)] 5.3}, P = 0.16). Internal consistency was high across items (Cronbach's alpha 0.86). Correlation with SGRQ, SF-36 and LCQ total scores was high. Following antibiotic treatment, mean (SD) LRTI-VAS total score improved from 18.1 (SD 9.9) to 26.1 (SD 6.6) (P < 0.001).

Conclusions: LRTI-VAS showed excellent validity, reliability and responsiveness to change and therefore appears a reliable tool for symptom measurement in non-CF bronchiectasis.