Patient Expectations as Predictors: Understanding Patient-Reported Outcomes in Musculoskeletal Conditions

Area of Science:

• Orthopedics
• Rehabilitation Medicine
• Health Psychology

Background:

• Patient expectations are crucial in shared decision-making and influence treatment outcomes.
• Existing research on patient expectations faces challenges like study heterogeneity, variability, and measurement tool validity.

Purpose of the Study:

• To investigate if initial patient expectations, measured by the Expectation for Treatment Scale (ETS), predict PROMIS physical function (PF) and pain interference (PI) scores.
• To assess the predictive power of patient expectations on physical function and pain interference at 6 and 12 weeks in patients with musculoskeletal conditions.

Main Methods:

• Prospective, longitudinal cohort study of 18-89 year olds with musculoskeletal conditions receiving outpatient physical therapy.
• Data collected included demographics, health information, ETS scores at baseline, and PROMIS PF and PI scores at baseline, 6, and 12 weeks.
• Statistical analyses involved descriptive statistics, quantile regression, and multiple imputations for missing data.

Main Results:

• The Expectation for Treatment Scale (ETS) significantly predicted PROMIS physical function (p < 0.001) and pain interference (p < 0.001) at 12 weeks, but not at 6 weeks.
• Multivariable models demonstrated medium explanatory power, with pseudo R² values of 0.28 for physical function and 0.15 for pain interference at 12 weeks.

Conclusions:

• Baseline patient expectations are a significant positive predictor of 12-week physical function and pain interference outcomes in musculoskeletal conditions.
• The model showed higher explanatory power for physical function compared to pain interference at 12 weeks.
• Clinicians can leverage patient expectations to better predict and potentially enhance patient outcomes in physical therapy.