Development and content validation of a self-completed, electronic Pediatric Asthma Symptom Diary

Childhood asthma is an important unmet need. To date, patient-reported outcome measures (PROMs) for children with asthma have used a combination of caregiver or proxy-reported and self-reported measures. No comprehensive measure is available to assess the severity and impact of daytime and nighttime asthma symptoms and rescue medication use for self-completion by children aged 6-11 years. This study aimed to develop a novel, interactive, electronic Pediatric Asthma Symptom Diary (ePASD) measuring self-reported key symptom severity and proximal impacts of asthma in young children with varying reading ability and disease severity, consistent with US Food and Drug Administration (FDA) PRO guidance and the International Society for Health Economics and Outcomes Research (ISPOR) good research practices.

A targeted literature review and clinician interviews were undertaken to characterize symptoms and impacts experienced by children with mild-to-severe asthma. Concept elicitation interviews (CEIs) were conducted with 44 children and their caregivers (30 US; 14 UK). Following item and digital application development, the ePASD was assessed for relevance, understanding, and interpretability through cognitive debriefing interviews (CDIs) with 21 US children. Face validity/translatability assessments were also performed.

Key measurement concepts included cough, wheeze, difficulty breathing, chest tightness/discomfort, nighttime awakening, and daytime activity limitations. Concept saturation was reached during CEIs for primary asthma-related daytime and nighttime symptoms and core impacts. Most CDI participants found the ePASD items clear, understandable, and comprehensive. Standardized training is anticipated to facilitate reliable child self-report.

The ePASD, a novel PROM for children aged 6-11 years with asthma, uses an innovative multimedia approach and has been developed in accordance with FDA PRO guidance and ISPOR good research practices, directly capturing the child's self-reported asthma symptoms, impacts on daily activities and nighttime awakening, and rescue medication use.