Poor perception of airway obstruction in children with asthma.

The aims of this study were to evaluate children's perception of asthma symptoms and to determine a clinically useful method for identifying poor patient perception of airway obstruction. Three methods were used to analyze the relationships among indices of lung function and perception of breathlessness in 35 children. Approximately half the children in our sample did not perceive either airway obstruction or bronchodilation. We propose that <20% improvement in visual analog scale scores post-bronchodilation may provide a simple index for identifying patients with poor perception of airway obstruction, who may be at risk for fatal or near-fatal asthma.