Goniometric reliability for a child with spastic quadriplegia.

Intrarater and interrater reliabilities were assessed for upper-extremity goniometric measurements of a 5-year-old girl with severe spastic quadriplegia. Percentage agreement was the method used to evaluate goniometric reliability of three motions bilaterally: shoulder flexion, shoulder abduction, and elbow extension. Intrarater reliability for each of the two raters was higher than interrater reliability. The mean differences and the range of differences between raters for each of the six motions measured also were recorded. There was wide variability in measurements both within and between raters. These results suggest that a difference of +/- 10-15 degrees in range of motion over time does not justify conclusions of either significant improvement or significant regression in a child with severe spastic cerebral palsy.