Determining the Reliability of a New Method for Measuring Joint Range of Motion Through a Randomized Controlled Trial

Objective To compare the reliability and validity of the Korean range of motion standard protocol (KRSP) for measuring joint range of motion (ROM) with those of the conventional ROM measurement using a goniometer. Methods We conducted a randomized controlled trial involving 91 healthy elderly individuals. We compared two strategies of measuring joint ROM to evaluate the reliability and validity of each standardized protocol: first, the KRSP based on the Chungnam National University guidelines and second, handheld goniometric measurement. In the first strategy, 3 examiners (1 rehabilitation doctor, 1 physical therapist, and 1 physical therapy student) independently measured joint ROM in 46 randomly selected subjects; in the second strategy, another 3 examiners (1 rehabilitation doctor, 1 physical therapist, and 1 physical therapy student) measured joint ROM in 45 randomly selected subjects. The reliability of each protocol was calculated using intraclass correlation coefficient, ICC(2,1), and root mean square error (RMSE). Results Both protocols showed good to excellent intra-rater reliability. With goniometer use, the inter-rater reliability was low-ICC(2,1), 95% confidence interval ranged from 0.643 (0.486-0.783) to -0.078 (-0.296-0.494)-and RMSE was high. With the KRSP, the inter-rater reliability ranged from 0.846 (0.686-0.931) to 0.986 (0.972-0.994) and RMSE was low. Conclusion ROM measurements using the KRSP showed excellent reliability. These results indicate that this protocol can be the reference standard for measuring ROM in clinical settings as an alternative to goniometers.