Does Dosage Matter? A Pilot Study of Hand-Arm Bimanual Intensive Training (HABIT) Dose and Dosing Schedule in Children with Unilateral Cerebral Palsy

Aim: We compared the efficacy of hand-arm bimanual intensive training (HABIT) in two doses (90 vs. 45 hours) and two schedules of the same dose (90 vs. 2 x 45 hours) on hand and daily functioning. Method: Eighteen children with unilateral cerebral palsy were randomized to receive 6 hours of daily training over 3 weeks, totaling 90 hours (Group 90, n = 9) or receive 6 hours of daily training over 1.5 weeks, totaling 45 hours (Group 2 x 45, n = 9). After 6 months, Group 2 x 45 received an additional 45 hours. Hand (Jebsen-Taylor Test of Hand Function, Assisting Hand Assessment) and daily functioning tests (Canadian Occupational Performance Measure, Pediatric Evaluation of Disability Inventory) were administered before, immediately after, and 6 months after interventions. Results: Both groups demonstrated significant improvements in hand and daily functioning after 90 hours (Group 90) or the first 45 hours (Group 2 x 45), without differences between groups. However, more children from Group 90 obtained smallest detectable differences in the Assisting Hand Assessment. The addition of the second bout of 45 hours (Group 2 x 45) did not lead to further improvements. Conclusions: As this study was powered to test for large differences between groups, future investigations on larger samples will be needed to compare differences at the two dosage levels.