Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jun;30(2):90-99.
doi: 10.1177/17589983251322537. Epub 2025 Mar 13.

Establishing the reliability and validity for GripAble: A handheld sensor-based dynamometry device

Elise Yee Yan Li  1 , Luke Steven Robinson  1 , Claire Stockdale  1   2
Affiliations

Establishing the reliability and validity for GripAble: A handheld sensor-based dynamometry device

Elise Yee Yan Li et al. Hand Ther. 2025 Jun.

Abstract

Introduction: Evaluation of maximum grip strength (MGS) is commonly conducted to guide intervention planning and evaluate treatment outcomes for individuals with hand or upper limb impairments. While the hydraulic Jamar dynamometer is recognised as the gold standard measurement instrument, it has several limitations and there has not been a consensus on whether alternative instruments can replace or complement it. This study aimed to determine whether a new electronic rehabilitation device, the GripAble, is a reliable and valid instrument for measuring the MGS of healthy adults when compared to the gold standard hydraulic Jamar dynamometer. It also sought to compare the user's experience when using the two instruments.

Methods: Fifty-five healthy adults completed two MGS assessments ten minutes apart using a standardised protocol. Test-retest and inter-instrument reliability were evaluated using intraclass correlation coefficient. Concurrent validity was established using a Bland-Altman plot. Relationship and level of agreement between measurements on the two devices were evaluated. Participants' user experience was explored through a quantitative survey.

Results: The GripAble was found to have excellent test-retest reliability (ICC = 0.971-0.975) and good-to-excellent inter-instrument reliability (ICC = 0.898-0.922) with the Jamar dynamometer. Its measurement output is equivalent to approximately 63.3% of that of the Jamar dynamometer. The mean difference value between the measurements on the two devices was 9.44 kg (SD = 4.47). Users preferred the GripAble.

Discussion: While the GripAble is a reliable MGS assessment instrument, it should not be used interchangeably with the Jamar dynamometer for repeated measurements of the same individual owing to the differences in their readings.

Keywords: Hand grip strength; muscle strength dynamometer; reliability; validity.

PubMed Disclaimer

Conflict of interest statement

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
Relationship Between the MGS Measurements Obtained with the GripAble and Jamar Dynamometer. Note. The solid red line and red text indicate simple linear regression, while the dotted black line indicates the zero-intercept linear fit created using TLS. MGS: maximum grip strength; R2: coefficient of determination.
Figure 2.
Figure 2.
A Bland-Altman Plot Demonstrating the Level of Agreement Between Measurements on the GripAble and Jamar Dynamometer. Note. LoA: limits of agreement.
See this image and copyright information in PMC

References

    1. de Putter CE, Selles RW, Polinder S, et al. Economic impact of hand and wrist injuries: health-care costs and productivity costs in a population-based study. J Bone Joint Surg 2012; 94: 56. - PubMed
    1. Rosberg HE, Carlsson K, Cederlund RI, et al. Costs and outcome for serious hand and arm injuries during the first year after trauma – a prospective study. BMC Public Health 2013; 13: 501. - PMC - PubMed
    1. Şahin F, Akca H, Akkaya N, et al. Cost analysis and related factors in patients with traumatic hand injury. J Hand Surg 2012; 38: 673–679. - PubMed
    1. Robinson LS, O'Brien L. Description and cost-analysis of emergency department attendances for hand and wrist injuries. EMA 2019; 31: 772–779. - PubMed
    1. Amini D. Hand impairments. In: Dirette DP, Gutman S. (eds). Occupational Therapy and Physical Dysfunction. 8th ed. Philadelphia: Wolters Kluwer, 2021, pp. 895–921.

LinkOut - more resources