Validity and reliability of a wearable-controlled serious game and goniometer for telemonitoring of wrist fracture rehabilitation.

Purpose: To determine the validity of wrist range of motion (ROM) measurements by the wearable-controlled ReValidate! wrist-rehabilitation game, which simultaneously acts as a digital goniometer. Furthermore, to establish the reliability of the game by contrasting ROM measurements to those found by medical experts using a universal goniometer.

Methods: As the universal goniometer is considered the reference standard, inter-rater reliability between surgeons was first determined. Internal validity of the game ROM measurements was determined in a test-retest setting with healthy volunteers. The reliability of the game was tested in 34 patients with a restricted range of motion, in whom the ROM was measured by experts as well as digitally. Intraclass-correlation coefficients (ICCs) were determined and outcomes were analyzed using Bland-Altman plots.

Results: Inter-rater reliability between experts using a universal goniometer was poor, with ICCs of 0.002, 0.160 and 0.520. Internal validity testing of the game found ICCs of - 0.693, 0.376 and 0.863, thus ranging from poor to good. Reliability testing of the game compared to medical expert measurements, found that mean differences were small for the flexion-extension arc and the radial deviation-ulnar deviation arc.

Conclusion: The ReValidate! game is a reliable home-monitoring device digitally measuring ROM in the wrist. Interestingly, the test-retest reliability of the serious game was found to be considerably higher than the inter-rater reliability of the reference standard, being healthcare professionals using a universal goniometer.

Trial Registration Number: (internal hospital registration only) MEC-AMC W17_003 #17.015.