Purpose: To investigate the association between physical therapy frequency and gross motor improvement in children with cerebral palsy (CP).
Materials and methods: This is a prospective cohort study of 442 children aged 2–12 years, Gross Motor Function Classification System levels I–V, from the Cerebral Palsy Follow-up Program and the Cerebral Palsy Register of Norway. Outcome was change in reference percentiles for the Gross Motor Function Measure (GMFM-66) between two subsequent assessments (N = 1056) analyzed in a linear mixed model.
Results: It was a dose response association between physical therapy frequency and gross motor improvement. Mean change was 4.2 (95% CI: 1.4–7.1) percentiles larger for physical therapy 1–2 times per week and 7.1 (95% CI: 2.6–11.6) percentiles larger for physical therapy >2 times per week, compared to less frequent physical therapy when analyzed in a multivariable model including multiple child and intervention factors. The only statistically significant confounder was number of contractures which was negatively associated with gross motor improvement.
Conclusions: When gross motor improvement is a goal for children with CP, more frequent physical therapy should be considered.