RW: Test-retest reliability of handheld dynamometry during a single session of strength assessment. Phys Ther 66:206-209

This retrospective study was undertaken to determine the test-retest reliability of hand-held dynamometer strength testing for 18 extremity muscle groups. To assess reliability, I compared three dynamometer strength scores recorded for each muscle group on the strength score forms of 30 neurologically involved patients, using the Pearson product-moment correlation and a one-way analysis of variance (ANOVA) for repeated measures. All correlations were significant (p <.01); the median and modal correlations were all.97 or.98. The ANOVA revealed significant differences in repeated dynamometer test scores only for hip and shoulder abduction. The results suggest that hand-held dynamometry can be a reliable assessment technique when practiced by a single experienced tester. Key Words: Muscle contraction, Musculoskeletal system, Physical therapy. Beasley, in 1956, clearly established the need for muscle strength testing methods that are more precise and objective than manual muscle testing.1 Using a manual force gauge, he demonstrated that differences in strength of 20 % to 25 % ar