Reliability and validity of short‐term performance tests for wheelchair‐using children and adolescents with cerebral palsy

AIM: To investigate the test-retest reproducibility of the Muscle Power Sprint Test (MPST), the 10 × 5-m sprint test, and the arm-cranking Wingate Anaerobic Test (WAnT) in children and adolescents with cerebral palsy (CP). A secondary objective was to assess the construct validity of the MPST. METHOD: Twenty-three participants with spastic CP (mean age 13 y 3 mo, range 7-18 y, SD 3.6 y; 18 males, five females, two classified as having spastic unilateral CP, 21 as having spastic bilateral CP) using a manual wheelchair for at least part of the day were recruited and tested in different rehabilitation settings in the Netherlands. Participants were classified as in Gross Motor Function Classification System Expanded and Revised (GMFCS-E&R) levels III and IV. RESULTS: Intraclass correlation coefficients (range 0.93-0.99; 95% confidence interval 0.82-1.0) for all variables indicated highly acceptable reproducibility. Limits of agreement analysis revealed satisfactory levels of agreement. The MPST variables demonstrated very strong significant positive correlations for peak power and mean power from both tests (peak power: r=0.91, p<0.001; mean power: r=0.88, p<0.001). INTERPRETATION: The MPST, the 10 × 5-m sprint test, and the arm-cranking WAnT are reproducible tests for measuring anaerobic performance and agility in adolescents with spastic CP who self-propel a manual wheelchair. The MPST has been shown to be a valid test to measure anaerobic performance in this population.