Initial evaluation of the Parent Cystic Fibrosis Questionnaire—Revised (CFQ-R) in infants and young children

BackgroundThere is an urgent need to evaluate treatments for young children with cystic fibrosis (CF); however, efforts have been hampered by a lack of reliable, practical endpoints. To examine whether a patient-reported outcome could be reliable in children 4 to 60 months of age, we assessed the psychometric properties of the modified Parent Cystic Fibrosis Questionnaire—Revised (CFQ-R) using data from the Infant Study of Inhaled Saline (ISIS). We also characterized patterns of symptom presentation and daily functioning in children in this age range to inform future measure development.MethodsParents (N = 314) completed the CFQ-R and Treatment Adherence Questionnaire (TAQ) at five quarterly visits, as well as a weekly Parent Symptom Diary.ResultsThe Parent CFQ-R demonstrated good construct validity and adequate internal consistency (α's .58–.75). Associations with age, TAQ, and Parent Symptom Diary were observed. The Treatment Burden scale demonstrated responsiveness to change.ConclusionsParents were reliable observers of young children's symptoms and daily functioning, and PROs show promise for this age group. Research is needed to identify key symptoms in infants and young children with CF, and to develop a parent proxy PRO according to FDA/EMA guidelines.