Magnitude and Reliability of Measurements of Muscle Strength across Trials for Individuals with Mental Retardation

The purpose of this investigation was to examine the magnitude and reliability of strength measures on the Nicholas Manual Muscle Tester for individuals with mental retardation. 17 subjects were given six trials with the dominant and nondominant flexor and extensor muscle groups. No significant differences were found between dominant and nondominant muscle groups by side or by muscle group. Interclass correlations ranged from .96 to .98 for six and three trials, respectively. It was concluded that the test was appropriate for reliably assessing strength in this population and that these individuals can achieve a sufficient magnitude on three trials for a reliable measure of strength.