Reliability and validity of the Body Awareness Rating Scale (BARS), an observational assessment tool of movement quality

Movement quality assessed by the Body Awareness Rating Scale (BARS) is used as an indicator of health and self-efficacy in patients with long-lasting musculoskeletal and mental health problems. The objective of the study was to examine reliability and construct validity of the movement quality scale. 25 patients and 25 healthy persons were included. Internal consistency was examined by Cronbach's α, reliability by intraclass correlation coefficient (ICCagreement) and measurement error reported by standard error of measurement (SEM) and smallest detectable change (SDC). Construct validity was examined by testing hypotheses of moderate association between the observational scale and the self-report Short-Form Health Survey (SF-36) subscales and the General Perceived Self-Efficacy Scale (GPSES). A hypothesis about the difference in scores between groups being expected to differ in health states was tested. Internal consistency (α) was 0.92. Inter-tester reliability was ICC = 0.99 and SEM = 0.8. The test-retest reliability was ICC = 0.96 and SEM = 1.4, implying that improvement should be above 3.3 (SDC) to claim a treatment effect. BARS was moderately correlated (0.30 ≤ rs < 0.60) with most SF-36 subscales and GPSES. The patients demonstrated less movement quality than healthy persons. Evidence was provided of high internal consistency and reliability in qualified testers. Construct validity was indicated, as BARS reflected various aspects of health and self-efficacy