Reliability and validity of a load cell device for hand grip strength assessment

ABSTRACT The grip strength is a complex measure influenced by factors such as gender, age, motivation, muscle training, handedness, height, weight, socioeconomic variables, and participation in specific sports or professions. It can be measured by dynamometers or by tension meters such as load cells (strain gauges). Reliability and validity are important psychometric properties, which analyze consistency and applicability of an instruments' measurement. Thus, the aim of this study was to evaluate the test-retest reliability and construct validity of a load cell device in isometric grip force measurements using a sample of asymptomatic subjects and patients with wrist and hand dysfunctions. Standardized methods of the upper limb positioning and randomization of the sample order were used. Statistical analysis of reliability was conducted by the ICC (Intraclass Correlation Coefficient) and the construct validity by Pearson correlation coefficient (r), with p