Kinematic predictors of performance on the Star Excursion Balance Test.

CONTEXT The Star Excursion Balance Test (SEBT) is composed of 8 reaching directions that are potentially measuring the same functional component, leading to the suggestion that the number of reach directions could be reduced without compromising the assessment of dynamic postural control. OBJECTIVE To determine whether the relationship of stance-leg angular displacement on normalized reach distance is a source of dynamic-postural-control measurement redundancy. DESIGN Single-session within-subjects design. SETTING Athletic training research laboratory. PARTICIPANTS 10 women and 10 men. INTERVENTIONS None. MAIN OUTCOME MEASURES Normalized reach distance and angular displacement at the knee and hip. RESULTS Stepwise regression revealed that hip flexion and knee flexion, separately and in combination, accounted for 62% to 95% of the variance in reach distances. CONCLUSION Similarity in lower extremity function could account for the previously observed measurement redundancy in the SEBT.