Working Alliance Inventory (WAI) and its relationship to patient-reported outcomes in painful musculoskeletal conditions

Purpose: Therapeutic alliance (TA) has been positively correlated to improvements in patient outcomes. This study examined the Working Alliance Inventory (WAI) relationship with changes in disability and pain intensity for patients receiving physical therapy (PT) treatment for acute and chronic musculoskeletal pain conditions.

Methods: Fifty participants were dichotomized into success or failure by the minimal clinically important difference (MCID) on region-specific patient-reported outcome measures (PROM) and Numeric Pain Rating Scale (NPRS). Regression and correlation statistics examined the relationship between WAI with change scores and quantity of PT. Independent t-tests compared WAI scores across categorical variables.

Results: WAI scores were higher for those meeting MCIDs on PROM and NPRS compared to those who did not. WAI scores were significantly correlated with improvement on region-specific outcome measures and NPRS. Regression analysis found the patient rating of the TA to be a positive predictor for improvement on regions specific outcome measures and NPRS.

Conclusions: Patients who rated the TA higher were more likely to meet the MCID for region-specific disability and pain intensity. Patient ratings of the TA were associated with improved change scores on pain rating and standardized outcome measures during a course of treatment for musculoskeletal pain conditions.Implications for rehabilitationPatients' early rating of the therapeutic alliance (TA) is associated with improvements seen on pain and functional outcomes.Physical therapists should assess the TA and use strategies to enhance the alliance to optimize patient's experiences with physical therapy.