Cognitive and psychological factors associated with shoulder function in patients with shoulder pain and asymptomatic individuals: a cross-sectional regression analysis

Purpose To investigate the associations between pain catastrophizing, kinesiophobia, anxiety, depressive symptoms, and pain intensity with shoulder function in adults with and without shoulder pain.Methods A cross-sectional study included 100 adults (50 with shoulder pain and 50 asymptomatic), matched by age and sex. Participants completed the Shoulder Rating Questionnaire, Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, Beck Anxiety and Depression Inventories, and Visual Analogue Scale. Multiple linear regression with HC3 robust standard errors was performed after assessing assumptions and multicollinearity. Sensitivity analyses and adjustment for confounders were conducted.Results The final model, including pain catastrophizing and severe pain (VAS ≥ 7), explained 90% of the variance in shoulder function (adjusted R2 = 0.898). Higher catastrophizing was associated with poorer function (B = −1.323; 95% CI −1.431 to −1.215), while severe pain was associated with an additional reduction of 8.99 SRQ points (95% CI −12.546 to −5.425). No other variables were independently associated. Sensitivity analysis showed consistent associations with lower explained variance (R2 ≈ 0.30).Conclusion Pain catastrophizing and severe pain intensity were the main factors associated with shoulder function, supporting the relevance of cognitive and pain-related dimensions within a biopsychosocial framework.