Investigation of Inter-Device Reliability Between the Squegg® Smart Dynamometer and the Baseline BIMS Digital Hand Grip Dynamometer

Objective: Accurate measurement of grip strength is crucial for evaluating muscle function and monitoring the rehabilitation process. The aim of this study was to assess the inter-device reliability of grip strength measurements obtained using the Baseline BIMS digital hand dynamometer and the Squegg smart hand dynamometer and to compare intra-rater reliability alongside measurement precision. Methods: A cross-sectional repeated-measures design was conducted between March and April 2025 with 50 healthy young adults (mean age 19.52 ± 1.02 years; 90% right-hand dominant). The measurement order of the devices was randomized for each participant. Maximum grip strength was measured three times on both the dominant and nondominant hands using each device (Squegg® and Baseline BIMS). A 15-second rest was given between measurements, and a 15-minute rest was given between devices. Inter-device reliability was assessed using the mean of three trials with the Intraclass Correlation Coefficient (ICC). Intra-rater reliability was assessed using the ICC for three trials on each hand for each device. Measurement precision was evaluated using the standard error of measurement (SEM) and the minimal detectable change (MDC). Results: Overall inter-device agreement was found to be “good” (ICC = 0.857; 95% CI [0.749–0.919]). Intra-rater reliability coefficients ranged from ICC = 0.959–0.962 for Squegg and ICC = 0.976–0.981 for BIMS, indicating “excellent” reliability for both devices. SEM values were 1.3 kg for both devices, with MDC90 values of 3.6–3.7 kg (MDC% = 8.5–9.8) for Squegg and 3.7 kg (MDC% = 8.2–9.7) for Baseline BIMS. Conclusion: Both inter-device and intra-rater analyses demonstrated that the Squegg and Baseline BIMS devices provided consistent, reliable measurements of grip strength. Owing to its practicality, portability, and digital features, Squegg offers a reliable alternative to Baseline BIMS for clinical settings and remote monitoring applications.