RESUMO
BACKGROUND: Questionnaires are an important component of epidemiologic studies. Maintaining compliance in longitudinal studies is a challenge, particularly from children and adolescents. OBJECTIVE: To implement a Web-based questionnaire for children and adolescents with asthma for daily self-completion, minimizing recall bias and maximizing compliance. METHODS: We determined symptoms, exposure to asthma triggers, peak expiratory flow rate, and medications taken, including dose and dose time. The Web-based system can be less time-consuming and a source of fewer errors than paper questionnaires and permits review of the data and compliance during the study. The Web programming of the questionnaire included branching, so that questions deemed irrelevant based on a previous response were not presented to participants, minimizing the completion time. RESULTS: Sixty-four students with asthma participated nearly daily for between 2 and 4 months. Financial incentives for the participants were calculated in real time based on completion rates. Monitoring of the subject's completion included an extensive administrative hierarchical alert system, enabling the staff to target individuals who fell behind in entries and needed the most encouragement. CONCLUSIONS: Similar compliance and completion rates were obtained using the Web-based questionnaire as reported for smaller paper questionnaires by parents of children. The Web-based system provides a mechanism to obtain daily responses directly from an age group not often accessible by traditional questionnaire approaches.
