In this Perspective, we suggest a process to improve physical and occupational therapists’ and families’ collaboration to provide appropriate, efficient, and effective evidence-based services to improve motor function, self-care performance, and participation in family and recreation activities for children with cerebral palsy (CP). This process is informed by 2 multisite prospective cohort studies (Move & PLAY and On Track). The heterogeneity of children with CP is described, limiting the utility of evidence from randomized controlled trials and systematic reviews to inform service planning for children with CP. An evidence-based alternative using prospective cohort studies that produce knowledge of determinants of outcomes important to children and families and methods for developmental monitoring using longitudinal developmental and reference percentile curves to inform individualized care is suggested. Guiding questions are provided to explore how knowledge of determinants and developmental monitoring can inform family-centered, collaborative, strengths-based, and focused service programs to support early development and function. Although this perspective paper is focused on children with CP, the research approach described for collection of useful information and the clinical method of data use may be helpful for people with other heterogeneous chronic health conditions in which physical and occupational therapists face similar challenges
