Validation of an asthma symptom diary for interventional studies

Objective-The Pediatric Asthma Diary was developed and validated to assess efficacy of interventions in children with asthma. Design, patients, and setting-Diary validation was performed in a three week, prospective study of 106 children aged 6-14 years with asthma. Children were classified at baseline as either stable (requiring no additional asthma treatment) or new onset/worse (requiring either addition of or increase in antiinflammatory treatment). Results-A daytime symptom scale and "day without asthma" were defined from diary questions. Both measures demonstrated significant validity and responsiveness to anti-inflammatory treatment. The stable group experienced a higher percentage of days without asthma during week 1 compared with the new onset/worse group (39.6% v 11.6%, respectively). The new onset/worse patients experienced significant improvement in days without asthma (24.5%) compared with stable patients (6.4%). Conclusions-The Pediatric Asthma Diary daytime symptom scale and day without asthma are acceptable measures for use in asthma intervention studies of children aged 6-14 years.