Social determinants of health and social vulnerability: How individual and community factors influence physical therapy patient outcomes in a public hospital system

Social determinants of health (SDOH) and social vulnerability play a significant role in determining health outcomes. SDOH can affect up to 80% of health outcomes, making them the single strongest predictor of health and wellness. The social vulnerability index (SVI), while initially established to measure public health preparedness, is often negatively correlated with health outcomes. Studies are lacking to quantify relationships between SDOH, SVI, and musculoskeletal outcomes in physical therapy patients. The purposes of the three studies were to establish the test-retest reliability and concurrent validity of the Health Leads Screening Tool (HLST), examine the relationship between community vulnerability and orthopedic physical therapy patient outcomes, and determine which individual factors are predictive of orthopedic physical therapy patient outcomes in a public hospital system. Test-retest reliability of the HLST and concurrent validity of the HLST with the Protocol for Responding to and Assessing Patient Assets, Risks, and Experiences (PRAPARE) were assessed in physical therapy patients. The HLST had excellent test-retest reliability in all nine domains and moderate concurrent validity in six of the nine domains. Next, a retrospective study examined if SVI predicted physical therapy outcomes when dichotomized into success and failure groups based on the Focus on Therapeutic Outcomes (FOTO) survey. SVI was a significant predictor of outcomes in patients with upper quarter diagnoses. In this group, patients in the second-fourth quartiles of SVI were 2.5 times more likely to be classified as failure compared to those in the first quartile. The number of visits that a patient attended was also a significant predictor of outcomes. Every additional visit that a patient attended increased their odds of success by 10%. A final study examined the role of individual factors in predicting physical therapy baseline levels of function, discharge levels of function, and amount of improvement during a plan of care (all measured via FOTO). Self-rated health and SVI explained 12.5% of the variation in baseline levels of function, while social needs, baseline scores, self-rated health, and SVI explained 31% of the variation in the amount of improvement and 62% of the variation in discharge scores.