Inter-Rater Reliability of a 6-Item Movement Control Test Battery in Individuals With and Without Chronic Non-Specific Low Back Pain

Abstract

Objective: The purpose of this study was to investigate the inter-rater reliability of the 6-item movement control test battery (MCTB) in individuals with and without chronic non-specific low back pain (CNLBP) using different rating methods, including individual tests, summation, and direction-specific tests, for movement control impairment detection through real-time observation. Methods: Forty-seven participants with and without CNLBP were recruited. Participants were asked to perform MCTB (flexion-specific tests: waiter's bow, sitting knee extension, and quadruped rocking backward; extension-specific tests: pelvic tilt, prone knee flexion, and quadruped rocking forward), while 2 raters simultaneously and independently observed the movement control. Inter-rater reliability was analyzed using the chi-square test, percentage agreement (PA), kappa coefficient, and prevalence-adjusted and bias-adjusted kappa (PABAK). Results: The chi-square showed significant associations (P < .05) between the 2 raters in all tests and grading methods. For PA, all grading methods showed an acceptable level (PA > 70%), except prone knee flexion and extension-specific tests. The acceptable kappa levels (kappa > 0.4) were obtained in the flexion-specific tests and all individual tests except the prone knee flexion. The kappa of the summation did not reach the acceptable agreement level; however, this method yielded acceptable inter-rater reliability after using PABAK (PABAK = 0.62). Conclusions: The findings support inter-rater reliability of the flexion-specific tests, summation, and most individual tests for clinical use. However, the prone knee flexion and the extension-specific tests should be used with caution.