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Published on: June 12, 2019
Grip strength in children: test-retest reliability using Grippit
E Svensson1, K Waling, C Häger-Ross
1Department of Community Medicine and Rehabilitation, Section for Physiotherapy, Umeå University, Sweden.
Insights
Grip strength testing in children using the Grippit shows good reliability for both peak and sustained measurements. Using the mean or best of three trials is recommended for accurate grip strength assessment.
Area of Science:
- Pediatric physical assessment
- Musculoskeletal function evaluation
- Biomechanical analysis in children
Background:
- Accurate grip strength measurement is crucial for assessing pediatric health and development.
- The Grippit instrument is increasingly used for grip strength assessment in children.
- Understanding the reliability of grip strength testing in different age groups is essential for clinical practice.
Purpose of the Study:
- To evaluate the test-retest reliability of the Grippit for measuring peak and sustained grip strength in children.
- To compare the reliability of single versus multiple trials (mean and best of three) for grip strength assessment.
- To analyze reliability across different age groups (6, 10, and 14 years).
Main Methods:
- A test-retest reliability study design was employed.
- Grip strength was measured twice in 58 children using the Grippit instrument.
- Statistical analyses included Intraclass Correlation Coefficient (ICC), Standard Error of Measurement (SEM%), coefficient of repeatability, and coefficient of variation.
Main Results:
- Good test-retest reliability was observed for both peak and sustained grip strength.
- The mean and best of three trials demonstrated comparable reliability.
- Reliability varied by age group, with higher reliability for 6- and 14-year-olds compared to 10-year-olds for peak grip strength.
Conclusions:
- Grip strength assessment using the Grippit provides good relative and absolute reliability in children.
- Recommends using three test trials for grip strength assessment in pediatric populations.
- The mean and best of three trials are equally reliable and suitable for clinical use.
Aim:
To examine the reliability of peak and sustained grip strength in children using the Grippit. We compared the reliability of one trial, the best and mean of three trials and the reliability within 6-, 10- and 14-year-old groups.
Design:
Test-retest study.
Methods:
Grip strength with the Grippit instrument was evaluated at two test occasions in 58 children. Intraclass correlation coefficient 2.1 (ICC), standard error of measurement (SEM) also expressed as a percentage value (SEM%), coefficient of repeatability and coefficient of variation were calculated.
Results:
The test-retest reliability was good for both peak and sustained grip strength. The mean and best of three trials were equally reliable. Peak grip strength best of three trials, for example, was more reliable for the 6-year-olds (ICC 0.96, SEM% 6.3) and 14-year-olds (ICC 0.96, SEM% 5.2) compared to the 10-year-olds (ICC 0.78, SEM% 12.5). For peak grip strength in the whole sample, there was a systematic bias with better performance at the second measurement.
Conclusion:
Grip strength assessment in children with Grippit results in good relative and absolute reliability for peak and sustained grip strength. We recommend that three test trials are used. The mean of and the best of three trials are comparable.
