Assessing Differences and Implications of Two Methods for Calculating Outcomes in the Lower Quarter Y-Balance Test.

Background: The Lower Quarter Y-Balance test (YBT-LQ) is a widely used tool in the field of sports medicine and rehabilitation. Interestingly, there are inconsistencies in the literature regarding the methodology for calculating YBT-LQ outcomes. Objective: The aim of this study is to examine whether calculating YBT-LQ outcomes based on maximal reach distance significantly differs from calculations based on mean reach distance. Material and methods: This cross-sectional study involved 100 healthy participants between the age of 18 and 25 years. The participants performed the YBT-LQ. Normalised reach (%) was calculated by dividing both the maximal and mean reach distances (cm) by the length of the lower limb (cm) and then multiplying the result by 100%. The composite score (%) was calculated by summing the maximal and mean reach distances in each direction, and then dividing the obtained values by three times the length of the lower limb, and finally multiplying the result by 100%. Results: The calculation method based on the maximal reach distance, as compared to the mean reach distances, yields significantly (p-value<0.001) higher values for all absolute (cm) and normalised (%) reaches, as well as composite score (%) in the YBT-LQ test. Conclusion: When comparing research findings using two calculation methods for YBT-LQ performance, it is important to consider that the maximal reach distance method yields higher values of 1.7-2.5 cm and 1.8-2.8% (respectively) for absolute and normalised outcomes. These variations highlight the importance of selecting an appropriate calculation method based on the specific objectives of the study and available resources. [ABSTRACT FROM AUTHOR]