Testing and validation of an isometric strength measurement device
University of New Brunswick
The reliability and validity of a novel isometric strength measurement device was found to be comparable to accepted commercial devices for elbow flexion and extension. Developed at UNB to test isometric elbow strength, the Limb Strength Measurement Device (LSMD), is a compact, accurate alternative to hand-held dynamometry (HHD) and isokinetic dynamometry (IKD). Simulated loading environments confirmed the reliability of the device’s measurement hardware and software in isolation, while indicating that the LSMD’s ability to self-stabilize was due in part to postural adjustments of the user. In situ analysis was based on a split-session, multiple-factors statistical design performed with 20 healthy adults. The resulting intersession, intra- and inter-rater reliability data showed that the LSMD was comparable to HHD and fixed-IKD. Modified Limits of Agreement plots and regression analysis provided validation of the LSMD compared to the fixed-IKD, yielding calibration formula that were capable of correcting for fixed and proportional measurement bias.