Reliability of the scapular dyskinesis test yes-no classification in asymptomatic individuals between students and expert physical therapists

BACKGROUND: Scapular dyskinesis is considered a risk factor for the shoulder pain that may warrant screening for prevention. Clinicians of all experience screen scapular dyskinesis using the scapular dyskinesis test yes-no classification (Y-N), yet its reliability in asymptomatic individuals is unknown. We aimed to establish Y-N’s intra- and inter-reliability between students and expert physical therapists. METHODS: We utilized a cross-sectional design using consecutive asymptomatic subjects. Six students and two experts rated 100 subjects using the Y-N. Cohen’s kappa (κ) and Krippendorff’s alpha (K-α) were calculated to determine intra- and inter-rater reliability. RESULTS: Intra- and inter-rater values for experts were κ=0.92 (95% confidence interval [CI], 0.91–0.93) and 0.85 (95% CI, 0.84–0.87) respectively; students were κ=0.77 (95% CI, 0.75–0.78) and K-α=0.63 (95% CI, 0.58–0.67). CONCLUSIONS: The Y-N is reliable in detecting scapular dyskinesis in asymptomatic individuals regardless of experience.