Mini-MACS: development of the Manual Ability Classification System for children younger than 4 years of age with signs of cerebral palsy

Abstract

Aim: To develop the Mini-Manual Ability Classification System (Mini-MACS) and to evaluate the extent to which its ratings are valid and reliable when children younger than 4 years are rated by their parents and therapists. Method: The Mini-MACS was created by making adjustments to the MACS. The development involved a pilot project, consensus discussions within an expert group, and the creation of a test version of the Mini-MACS that was evaluated for content validity and interrater reliability. A convenience sample of 61 children with signs of cerebral palsy aged 12 to 51 months (mean age 30.2mo [SD 10.1]) were classified by one parent and two occupational therapists across a total of 64 assessments. Agreement between the parents' and therapists' ratings was evaluated using the intraclass correlation coefficient (ICC) and the percentage of agreement. Results: The first sentence of the five levels in the MACS was kept, but other descriptions within the Mini-MACS were adjusted to be more relevant for the younger age group. The ICC between parents and therapists was 0.90 (95% confidence interval [CI] 0.79–0.92), and for the two therapists it was 0.97 (95% CI 0.78–0.92). Most parents and therapists found the descriptions in the Mini-MACS suitable and easy to understand. Interpretation: The Mini-MACS seems applicable for children from 1 to 4 years of age.