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

Objectives: To evaluate the inter-tester reliability of two common tests for assessing hip and groin injuries, using a protocol closely reflecting normal clinical conditions. Design: Same-session, single-trial, inter-tester reliability study. Setting: Elite European football academy. Participants: Two testers and fifty-eight football players aged 14–21 years. Main outcome measures: Inter-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. Results: Both 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. Conclusion: The squeeze and the BKFO tests demonstrated excellent inter-tester reliability in elite academy football players, using a protocol reflective of normal clinical conditions