1 Department of Health, Kinesiology, & Applied Physiology, Concordia University, Montreal, QC, Canada. Electronic address: elizabeth.teel@concordia.ca.
2 School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada; Division of Neonatology, Department of Pediatrics, Montreal Children's Hospital, McGill University Health Centre, Montreal, QC, Canada; Department of Neurology and Neurosurgery, Montreal Children's Hospital, McGill University Health Centre, Montreal, QC, Canada.
3 Département des Sciences de l'Activité Physique, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada.
4 School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada; Division of Pediatric Emergency Medicine, Department of Pediatrics, Montreal Children's Hospital, McGill University Health Centre, Montreal, QC, Canada.

Objective: To determine if performance on symptom, cognitive, balance, fatigue, physical activity, and quality of life outcomes at 4-weeks post-injury in children with concussion differs based on acute 5P risk classification.

Design: Prospective cohort.

Setting: Laboratory.

Patients: Sixty-two children (age: 13.27 ± 2.50 years; 29 (46.7%) females) with diagnosed concussion.

Interventions: Not applicable.

Main outcome measures: Patient demographics and post-injury assessments were completed within 72 hours of concussion and used to classify patients as "high", "moderate", or "low" PPCS risk. Children then completed a multi-modal assessment battery at 4-weeks post-concussion. Kruskal-Wallis assessments analyzed whether study outcomes differed between 5P risk groups.

Results: Significant group differences were observed in symptom (?²(2)= 9.76, p=0.008), fatigue (?²(2)= 14.60, p<0.001), physical activity (?²(2)= 15.76, p<0.001), and quality of life (?²(2)= 7.82, p=0.02) outcomes. The low-risk group had fewer symptoms and less fatigue but increased physical activity levels and quality of life compared to the high-risk group. No significant differences in cognitive or balance outcomes were observed (p>0.05).

Conclusion: The 5P rule provides clinicians with valuable prognostic information related to PPCS and self-reported outcomes 4-weeks post-concussion, but not objective cognitive or balance outcomes. This information may help clinicians prioritize treatment resources to children most at-risk of prolonged concussion recovery.