The research team drew on nationwide Medicare claims to identify 236,995 fee-for-service beneficiaries who had an outpatient visit for new onset neck pain in 2021. The team calculated state-level rates of care utilization for neck pain overall and separately for the two most frequently used provider types, chiropractic and primary care. The mean state-level rate of care utilization for new onset neck pain was 188.72 per 1000 beneficiaries.

Northern plains and mountain states exhibited higher rates of care utilization for neck pain overall, higher utilization of chiropractic services, and lower utilization of primary care. In those regions, an older adult who developed neck pain was more likely to be seen by a chiropractor and less likely to be seen by a primary care physician than a counterpart elsewhere in the country. The researchers also modeled associations between provider utilization and sociodemographic and health-related factors at the population level.

Chiropractic care utilization was positively associated with better population health status and with the prevalence of low back pain, a related spinal condition often managed by the same provider workforce. Low back pain prevalence was negatively associated with primary care utilization for neck pain, meaning that in states where low back pain was more common, beneficiaries with new neck pain were less likely to be treated in primary care settings. The study also assessed predictors of which specialty a patient saw first, using regression models to estimate how sociodemographic risk factors related to the choice between chiropractic and primary care.

The authors frame these results against prior evidence suggesting substantial geographic variability in the availability and utilization of nonpharmacological therapies in the United States. Clinical practice guidelines recommend nonpharmacological therapies as a first-line approach for neck pain, and characterizing utilization patterns among older adults yields insight into whether guideline-recommended services are reaching the people who need them. As an observational analysis of claims data, the study has inherent boundaries.

It captures fee-for-service beneficiaries in 2021 and cannot speak directly to Medicare Advantage enrollees, younger adults, or people whose neck pain never generated a billed outpatient visit. Associations measured at the state level describe populations, not individual care decisions, and do not establish that regional health status or low back pain prevalence caused the differences in provider choice. Utilization rates also measure volume of visits rather than quality of care or clinical outcomes, so the analysis cannot determine whether higher chiropractic utilization translated into better pain relief or function for beneficiaries.

Even with those caveats, the scale of the variation is notable. The authors conclude that the study demonstrates significant geographic variation in utilization for neck pain by provider specialty among Medicare fee-for-service beneficiaries, along with significant associations between provider utilization and sociodemographic factors. Looking ahead, the team calls for future research to investigate disparities in care access and utilization for neck pain across sociodemographic groups, with the aim of informing efforts toward health equity.

Subject of Research: Geographic variation in chiropractic and primary care utilization for new onset neck pain among Medicare fee-for-service beneficiaries

Article Title: Geographic variation in utilization of chiropractic and primary care for new onset neck pain among Medicare fee-for-service beneficiaries in the United States in 2021

Article References: Grout, L., Anderson, B., Hannah, A., MacKenzie, T., Moonaz, S., & Whedon, J. (2026). Geographic variation in utilization of chiropractic and primary care for new onset neck pain among Medicare fee-for-service beneficiaries in the United States in 2021. BMC Health Services Research. https://doi.org/10.1186/s12913-026-15531-w

Image Credits: AI Generated

DOI: 10.1186/s12913-026-15531-w

Keywords: neck pain, chiropractic, primary care, Medicare, geographic variation, health services research, older adults, spatial analysis, low back pain, health equity, claims data, nonpharmacological therapy