Reliability and Validity of the Star Excursion Balance Test for Evaluating Dynamic Balance of Upper Extremities

Background: Upper extremity (UE) dynamic balance is a significant physical fitness ability, which includes high-level neuromuscular proprioception, joint mobility, force, and coordination. The evaluation methods of UE dynamic balance are insufficient and lack experimental support. The Star Excursion Balance Test (SEBT) is a reliable assessment of dynamic balance and injury risk of the lower extremity. Hypothesis: The UE-SEBT is a reliable and reproducible approach for evaluating dynamic balance of UEs. Study Design: Observational study. Level of Evidence: Level 4. Methods: This cross-sectional study recruited 65 healthy adults. All participants were required to complete UE-SEBT, UE Y-balance test (UE-YBT), maximal voluntary isometric contraction (MVIC) of UE, closed kinetic chain UE stability test (CKCUEST), trunk flexor endurance test (TFET), trunk extensor endurance test (TEET), and lateral trunk endurance test (LTET). Intra- and inter-rater reliability and the correlation of UE-SEBT with other outcomes were measured. Results: Among the participants, the intra- and interoperator reliability of UE-SEBT in all directions and composite score achieved a moderate-to-excellent (intraclass correlation coefficients [ICC], 0.729-0.946) reliability. For validity, the UE-SEBT had a moderate to very strong correlation with UE-YBT ( r = 0.315-0.755, P < 0.01) and a strong correlation with CKCUEST ( r = 0.4-0.67, P < 0.01). Furthermore, the UE-SEBT performance showed weak-to-strong correlations with MVIC ( r = 0.26-0.43, P < 0.05). UE-SEBT was also correlated with LTET, TEET, and TFET to varying degrees. Conclusion: UE-SEBT has good reliability and validity to assess UE dynamic balance compared with other tests. Clinical Relevance: UE-SEBT can be used as a clinical assessment method to evaluate UE dynamic balance and injury prevention.