Y-balance test: a reliability study involving multiple raters

The Y-balance test (YBT) is one of the few field expedient tests that have shown predictive validity for injury risk in an athletic population. However, analysis of the YBT in a heterogeneous population of active adults (e.g., military, specific occupations) involving multiple raters with limited experience in a mass screening setting is lacking. The primary purpose of this study was to determine interrater test-retest reliability of the YBT in a military setting using multiple raters. Sixty-four service members (53 males, 11 females) actively conducting military training volunteered to participate. Interrater test-retest reliability of the maximal reach had intraclass correlation coefficients (2,1) of 0.80 to 0.85 with a standard error of measurement ranging from 3.1 to 4.2 cm for the 3 reach directions (anterior, posteromedial, and posterolateral). Interrater test-retest reliability of the average reach of 3 trails had an intraclass correlation coefficients (2,3) range of 0.85 to 0.93 with an associated standard error of measurement ranging from 2.0 to 3.5cm. The YBT showed good interrater test-retest reliability with an acceptable level of measurement error among multiple raters screening active duty service members. In addition, 31.3% (n = 20 of 64) of participants exhibited an anterior reach asymmetry of >4cm, suggesting impaired balance symmetry and potentially increased risk for injury.