A Naturalistic Experiment Evaluating the Impact of Medicaid Treatment Reimbursement Changes on Opioid Prescribing and Patient Outcomes Among Patients With Back Pain (Back on Track)

Back pain is one of the most common reasons patients seek medical care, and it can have a big impact on patients' quality of life and functioning. Patients and providers are becoming more frustrated with common back pain treatments like the long-term use of opioid medications and steroid injections, which have been shown to have limited long-term impact on patients' pain and day-to-day functioning and can have safety risks.

The State of Oregon recently changed what back and neck pain treatments they cover for its Medicaid enrollees. This started to affect those insured by Medicaid in July 2016 and was implemented by January 2018. These changes ended payments for treatments like long-term opioid therapy and injections. They also expanded coverage for nondrug treatments, such as acupuncture, osteopathic or chiropractic manipulation, physical/occupational therapy, and cognitive behavioral therapy. While experts agree that opioid use must be reduced, Oregon is among the first states to try such strong measures to promote nondrug treatments and prevent the use of long-term opioid treatment for back and neck pain.

The Oregon Medicaid reimbursement changes for back and neck pain treatment create the opportunity for a "natural experiment." In this mixed-methods, observational study, we will evaluate the impact of the reimbursement changes by comparing outcomes among patients with back pain in Oregon who will have access to these expanded nondrug treatments to similar patients seen in comparable clinics in California where expanded services for back and neck pain are not covered by the type of comprehensive payer incentive undertaken in Oregon.

Specifically, we will use electronic health record, Medicaid claims data, and data obtained from a longitudinal patient survey to assess the impact of the changes on:

• Patients' pain severity, pain related functioning, and satisfaction with care
• Patients' use of pain-related health care services
• Opioid use
• Unintended consequences, such as the use of illicit drugs (While we expect the Oregon Medicaid change to result in many positive changes, limiting the use of opioids and pain reducing procedures like injections may motivate some individuals to use drugs that were not prescribed by their doctor.)

In addition, we will use qualitative research methods to characterize the facilitators and barriers experienced by patients, health care providers, and clinic administrators and staff in adopting the Medicaid reimbursement changes and their satisfaction with the constellation of available and utilized services.

Thus, this study has three components: 1) patient survey, 2) administrative data-based study (data-only), and 3) qualitative evaluation. This record focuses on the component of the study in which subjects are able to enroll - the patient survey.