Rationale: Alternative scales to measure dyspnea and perceived exertion have been sought due to concerns regarding understanding and validity of any Borg scale in pediatric populations.
Objectives: To demonstrate content validity of Dalhousie Dyspnea and Perceived Exertion Scales developed for children and adolescents.
Methods: We obtained ratings for dyspnea and perceived exertion using both Borg CR-10 and Dalhousie Scales during incremental cycle exercise in 100 children and adolescents, healthy or with respiratory disease. Content validity was determined by correlating perceived leg exertion rating versus heart rate or %peak work capacity and dyspnea rating versus ventilation expressed as %peak ventilation. The stimulus-perceptual response was modeled as a quadratic function with a delay term. Reproducibility, cross-modality usage, and language effects were assessed in a small group of Italian children during treadmill exercise.
Measurements and main results: Pictorial ratings of dyspnea and perceived exertion measured by both scale ratings rose as expected with increasing exercise intensity in children and adolescents, demonstrating excellent correlation between perceived leg exertion versus exercise intensity and dyspnea rating versus ventilation (median Spearman ρ ≥ 0.9) with either scale. There were no systematic differences in dyspnea or perceived exertion ratings between children with or without respiratory disease. Understandability and reproducibility of the Dalhousie scales was affirmed in Italian-speaking subjects performing treadmill exercise.
Conclusions: Dalhousie Dyspnea and Perceived Exertion Scales offer an alternative to the Borg scale for use during exercise in pediatric subjects. Children and adolescents exhibit large variation in patterns of ratings of dyspnea and perceived exertion in incremental exercise.
Keywords: pediatric; psychophysical function; rating scale.