Objective and background: The Fifteen-Count Breathlessness Score (15CBS) has been reported to quantify breathlessness. The aim of this study was to determine the reliability and validity of the 15CBS in adults with COPD.
Methods: Using an observational correlation design, subjects with clinical signs and symptoms of COPD were videotaped performing the 15CBS at a self-selected (task 1) and an 8-s counting pace (task 2), on two occasions with 5-min rest between attempts. Respiratory-related quality of life questionnaires, self-report shortness of breath measures and pulmonary function tests were completed by all subjects.
Results: Thirty subjects completed the protocol. No significant differences and good linear relationships were calculated for the 15CBS within subjects (task 1 P = 0.32, r = 0.75 and task 2 P = 1.00, r = 0.86) and between assessors (task 1 P = 0.57, r = 0.99 and task 2 P = 0.21, r = 0.75). No significant relationships were evident between the 15CBS and shortness of breath or quality of life scores. Significant relationships existed between the 15CBS and FVC (litres and per cent predicted).
Conclusion: Most subjects completed the 15CBS using one breath, limiting discrimination between subjects with differing degrees of breathlessness. Although data from this study confirmed that the 15CBS is a reliable procedure within people with COPD, further modification is required to increase the validity and discriminative ability of this instrument.