The inter-tester reliability of the squeeze and bent-knee-fall-out tests in elite academy football players

Abstract

ObjectivesTo evaluate the inter-tester reliability of two common tests for assessing hip and groin injuries, using a protocol closely reflecting normal clinical conditions. DesignSame-session, single-trial, inter-tester reliability study. SettingElite European football academy. ParticipantsTwo testers and fifty-eight football players aged 14–21 years. Main outcome measuresInter-tester reliability of the squeeze (in approximately 45° hip flexion) and bent-knee-fall-out (BKFO) tests, evaluated with intraclass correlation coefficients (two-way mixed, single measure) and minimal detectable change. ResultsBoth tests demonstrated excellent inter-tester reliability. The intraclass correlation coefficients were 0.92 (95% CI: 0.87–0.95) for the squeeze test, 0.91 (95% CI: 0.67–0.96) for the BKFO test on the right side and 0.92 (95% CI 0.87–0.95) for BKFO on the left side. The minimal detectable changes were 7.21 mmHg for the squeeze test, 0.95 cm and 0.75 cm for BKFO (right) and BKFO (left) respectively. ConclusionThe squeeze and the BKFO tests demonstrated excellent inter-tester reliability in elite academy football players, using a protocol reflective of normal clinical conditions.