Intertester reliability of the hand-held dynamometer for wrist flexion and extension

Area of Science:

• Biomechanics
• Musculoskeletal assessment
• Rehabilitation science

Background:

• Accurate measurement of muscle strength is crucial for clinical assessment and research.
• Hand-held dynamometers are commonly used for quantifying muscle strength.
• Intertester reliability is essential for consistent and dependable strength evaluations.

Purpose of the Study:

• To evaluate the intertester reliability of a hand-held dynamometer for assessing wrist flexor and extensor muscle strength.
• To determine the consistency of strength measurements obtained by different testers.
• To identify potential limitations in using hand-held dynamometers for wrist muscle strength assessment.

Main Methods:

• Twenty healthy subjects participated in the study.
• Three testers performed the break test to measure wrist flexor and extensor muscle strength.
• Two strength measurements were recorded per muscle group by each tester.
• Data were analyzed using Pearson product-moment correlation coefficients, intraclass correlations, and ANOVA for repeated measures.

Main Results:

• High Pearson product-moment correlations (0.89–0.95) and intraclass coefficients (0.85–0.91) were observed between testers.
• Analysis of variance (ANOVA) revealed statistically significant differences between testers for both wrist flexion and extension (p < .05).
• Despite strong correlations, significant intertester variability was detected.

Conclusions:

• The hand-held dynamometer demonstrated good correlation between testers for wrist muscle strength measurement.
• However, significant differences between testers suggest limited intertester reliability.
• Clinical application requires careful consideration of potential variability in strength measurements obtained by different individuals.