OBJECTIVES: To establish longitudinal validation of a new tool, the Asthma Symptom Tracker (AST). AST combines weekly use of the Asthma Control Test with a color-coded graph for visual trending. METHODS: Prospective cohort study of children age 2 to 18 years admitted for asthma. Parents or children (n = 210) completed baseline AST assessments during hospitalization, then over 6 months after discharge. Concurrent with the first 5 AST assessments, the Asthma Control Questionnaire (ACQ) was administered for comparison. RESULTS: Test-retest reliability (intraclass correlation) was moderate, with a small longitudinal variation of AST measurements within subjects during follow-ups. Internal consistency was strong at baseline (Cronbach's a 0.70) and during follow-ups (Cronbach's a 0.82-0.90). Criterion validity demonstrated a significant correlation between AST and ACQ scores at baseline (r = 20.80, P , .01) and during follow-ups (r = 20.64, 20.72, 20.63, and 20.69). The AST was responsive to change over time; an increased ACQ score by 1 point was associated with a decreased AST score by 2.65 points (P , .01) at baseline and 3.11 points (P , .01) during follow-ups. Discriminant validity demonstrated a strong association between decreased AST scores and increased oral corticosteroid use (odds ratio 1.13, 95% confidence interval, 1.10-1.16, P , .01) and increased unscheduled acute asthma visits (odds ratio 1.23, 95% confidence interval, 1.18-1.28, P , .01). CONCLUSIONS: The AST is reliable, valid, and responsive to change over time, and can facilitate ongoing monitoring of asthma control and proactive medical decision-making in children. Pediatrics 2013;132:e1554-e1561.
- Asthma control
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health