Reliability and Concurrent Validity of a Low-Cost Handgrip Dynamometer: The Camry

Area of Science:

• Biomedical engineering
• Clinical kinesiology
• Health sciences

Background:

• Handgrip strength testing is a valid and reliable measure of health.
• High costs of traditional dynamometers limit accessibility in various settings.
• The Camry dynamometer presents a more affordable option for fitness surveillance.

Purpose of the Study:

• To evaluate the test-retest reliability of the Camry dynamometer.
• To assess intermodel and interinstrument reliability (Camry vs. TKK dynamometer).
• To determine the concurrent validity of the Camry dynamometer using calibrated weights.

Main Methods:

• A comparison study involving a TKK 5401 and two Camry EH101 dynamometers (new and old).
• Intrainstrument and interinstrument reliability were assessed.
• Concurrent validity was evaluated using calibrated known weights and the Bland-Altman method.

Main Results:

• The Camry dynamometer exhibited very high intrainstrument reliability (test-retest).
• Small mean differences were observed between Camry and TKK dynamometers.
• The Camry dynamometer demonstrated smaller systematic errors in concurrent validity compared to the TKK.

Conclusions:

• The Camry dynamometer is a highly reliable and valid tool for handgrip strength assessment.
• Its affordability makes handgrip strength testing more accessible in diverse healthcare and fitness settings.
• The device maintains accuracy and durability even after extensive use.