Youth with physical disabilities face greater restrictions to participation in community-based activities than their typically developing peers, which can lead to poor health outcomes. Emerging treatment approaches aimed at improving activity and participation have shifted from focusing only on impaired body functions towards the performance of functionally meaningful activities within the youth's natural environment. It is unclear, however, whether targeting intervention at the activity/participation level can, at the same time, result in improvement of personal functional skills (e.g., reaching) and body functions (e.g., range of motion) -components also important to address and maintain within the rehabilitation process. Together with key community-based stakeholders including youth/parents, clinicians, and policy-makers, the investigators plan, therefore, to examine whether engaging in a 6-week community based activity (e.g., joining a sledge hockey team, boccia) can lead to a significant improvement in three key body functions: motor, cognitive and affective functions. Eight participants with physical disabilities will take part in the study and engage in an activity program of their own choice. Changes in their body functions (e.g., movement-related functions, attention, behavior, mood) will be measured multiple times before, during and after the engagement in an individualized activity/program. Findings of this pilot study analyzed with input from key stakeholders can advance the investigators understanding about methods for testing complex and unique individual-based interventions. This can guide clinicians, families and policy-makers to select effective approaches that not only promote participation but can also facilitate additional (motor and mental) benefits from one single intervention. Such findings may also reduce the burdens on the healthcare system as well as on the youth and families.

Youth with physical disabilities experience restrictions to participation in community-based activities, which can lead to poor health outcomes. Currently, activity-based treatment approaches that are client-centered and implemented in the youth's natural environment are considered recommended practice. It is unclear, however, whether targeting intervention at the activity and participation level (e.g. playing boccia) can result in improvement of body functions (e.g., joint mobility, balance) as well as in participation - two key outcomes of pediatric rehabilitation programs. Research suggests that the opportunity to practice therapist-prescribed exercise programs is positively associated with physical gains. However, the impact of participation in a chosen real-life activity that is meaningful to the youth on a range of body functions has not yet been established and effective methods for testing complex individual-based interventions and outcomes are lacking. With funding received from the Canadian Institutes of Health Research, the investigators have proven the effectiveness of the PREP intervention, i.e., Pathways and Resources for Engagement and Participation, in promoting youth participation in meaningful activities across two provinces. Using the PREP approach, the purpose of this pilot study is to 1) employ an interrupted time series (ITS) design in order to generate preliminary evidence on the effectiveness of participants engagement in a 6-week community-based activity program (e.g., team sledge hockey) on 3 body functions (i.e., motor, cognitive and affective) as well as on the performance of the selected activity. An 18-week interrupted time series design with multiple baselines across 8 participants with physical disabilities (e.g., cerebral palsy, spina bifida) will be employed. Each activity, individually selected by the participants, will be analyzed using the task analysis approach in order to identify the underlying body functions necessary for the chosen activity. These functions, i.e., motor (measured using the Spinal Alignment and Range of Motion Measure, the Functional Reach Test, the Trunk Impairment Scale and the Jamar dynamometer), cognitive and affective (using the Behavior Assessment System for Children), will then be measured multiple times throughout the entire study, resulting in overall 32 trajectories of change in body functions (8 participants X 3 body functions) and additional 8 trajectories representing change in activity performance (using the Canadian Occupational Performance Measure). Two experts will independently analyze each trajectory using visual inspection and an innovative analytical solution, i.e., a combination of segmented regression and mixed-effect modelling, will be performed to estimate the overall effectiveness of the intervention across participants. This interdisciplinary research team, including three researchers in the field of childhood disability (occupational therapy, physical therapy and pediatric medicine), has partnered with seven key stakeholders and will work collaboratively throughout the research process. This early study in the area will build knowledge about alternative clinical trials that can generate evidence applicable to practice. Findings can eventually inform decision-making by guiding clinicians, families and policy-makers in appraising the benefits of participation-based therapies on improving functional capacities and actual performance of meaningful life activities. Describing the multiple benefits potentially generated by one single intervention can facilitate the development of efficient youth-engaging therapies, and thereby contributing to the improvement of the provision of pediatric rehabilitation services.

Inclusion Criteria:

• have a physical disability (e.g., cerebral palsy, spina bifida, musculoskeletal disorders, muscular dystrophy)
• restricted mobility, such as an inability to navigate all surfaces and stairs independently and safely without the use of aids, physical assistance or external support

Exclusion Criteria:

• Youth who are recovering within the first year following a severe brain injury or an orthopedic surgery will be excluded, as their functional capacities are less likely to be stable.