Reliability and validity of the hand reach star excursion balance test

Abstract

Measuring dynamic postural control and mobility using task-based full-body movements has been advocated. The star excursion balance test (SEBT) is well-established, but it does not elicit large upper body joint movements. Therefore, the hand reach star excursion balance test (HSEBT) was developed. The purpose of the current study was to assess the inter-rater and test-retest reliability and validity of the HSEBT. Twenty-nine healthy male subjects performed ten HSEBT reaches on each leg on four different occasions, led by three different raters. Reach distances were recorded in centimeters and degrees. Then, twenty-eight different healthy males performed the HSEBT while using a standard motion capture system. Reliability was assessed using the intraclass correlation coefficient (ICC) (range 0.77–0.98). Stability of measurement was assessed using the standard error of measurement (SEM) (range 0.3–2.8 cm and 1.7°–2.6°) and coefficient of variation (CV) (range 2.1–14.6%). Change scores were obtained using minimal detectable change (MDC 95 ) (range 0.9–7.9 cm and 4.7°–7.2°). Observed (Max m ) and calculated (Max kin ) maximum hand reach measurements showed good to excellent correlations. Bland Altman analysis established a fixed bias for all tests, which can be partially explained by the kinematic calculations. In conclusion, the HSEBT is a valid and reliable full-body clinical tool for measuring dynamic postural control and functional joint mobility.