Reliability of the selective motor control scale in children with cerebral palsy

• Published in: Advances in physiotherapy 2009, Vol.11 (2), p.58-63
• Main Authors: Löwing, Kristina, Brogren Carlberg, Eva
• Format: Article
• Language: English
• Subjects: Inter-rater reliability; test-retest reliability; weighted Kappa
• ISSN: 1403-8196; 1651-1948
• DOI: 10.1080/14038190801999620

The aim of this study was to determine inter-rater and test-retest reliability of a scale for assessing selective motor control (SMC) in the dorsiflexors of the ankle. A consecutive sample of 40 children with cerebral palsy (CP), aged 3-16 years (median age 7 years) participated in the study. Thirty children had a bilateral form of CP and 10 a unilateral form, and they were classified into Gross Motor Function Classification System levels I-V. The SMC scale ranges from 0 (indicating no ankle movement) to 4 (indicating isolated SMC through available range of motion with balanced activity in m. tibialis anterior). The inter-rater reliability was assessed simultaneously by three assessors. The test-retest reliability was achieved through a second assessment of 29 of the children, at a different occasion. The statistical analysis included a weighted kappa coefficient of agreement (Kw). The inter-rater reliability showed fair/good to strong agreement between pairs of raters (Kw=0.58-0.77). The test-retest reliability was strong (Kw=0.88-1). Since the inter-rater reliability varied between fair/good to strong and the test-retest reliability was strong, we conclude that repeated evaluations should preferably be performed by the same rater.