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The impact of physical therapy direct access policy on opioid shipments and opioid-related deaths: A
Geronimo Bejarano1, Peter Hull2,3, James J Young4,5
1Department of Health Services, Policy, and Practice, Brown University, Providence, Rhode Island, United States of America.
Background:
We exploit state-level policy changes for physical therapy direct access to estimate the effect of enacting direct access physical therapy policy on per-capita opioid pill volume (PCPV) and opioid-related deaths (ORD) compared to states without direct access to physical therapy.
Methods:
We used a staggered difference-in-differences analysis to assess changes in PCPV and ORD for states that did (treatment states) and did not enact (control states) direct access physical therapy policies between 2006-2014. Various sensitivity analyses including synthetic control methods were used to check the robustness of our results.
Results:
Treatment states had higher baseline PCPV (29.9 vs. 27.3) and ORD (27.2 vs. 16.9) compared to the control states. Pre-trends in PCPV and ORD were parallel between treatment and control states. After direct access physical therapy policies were enacted, PCPV was significantly reduced by -4.6 (95% confidence interval: -6.2 to -3.0) percentage points, a 15.4% relative reduction. There was no significant difference in ORDs (-2.3 [95% confidence interval: -7.2 to 2.6]).
Conclusion:
Direct access physical therapy policies significantly reduced PCPV but not ORDs. Our results suggest that administrative barriers to physical therapy may lead to greater opioid reliance and reduced population health.
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