# Effect of the patient-centered medical home on geographic and racial disparities in health care access

> **NIH AHRQ R03** · UNIVERSITY OF SOUTH CAROLINA AT COLUMBIA · 2020 · $49,998

## Abstract

Recent reviews of the overall quality of legislative initiatives to bolster preventative care and deter costs
through the adoption of the Patient-Centered Medical Home (PCMH) model have been mixed. The reasons for
these findings vary, and important gaps exist in our understanding of the circumstances in which some medical
homes apparently flourish while others do not. In particular, the degree to which geography and associated
social determinants of health drive variations in care quality is not well understood. This understanding is
critical for promoting access standards of service availability given the geographic variation in which the
medical homes are reaching the marketplace. As in other states, South Carolina’s Medicaid program recently
began a state-established initiative to allow enrollees to obtain care through recognized PCMHs that
participated in Medicaid Managed Care (MMC). Since that time, beneficiaries have been eligible to self-enroll
into 297 of the 367 medical homes that are recognized by the National Committee for Quality Assurance and
that participate in MMC. Although the program is available to enrollees across the state, 10% of the total
Medicaid population must travel outside of their county of residence to access a PCMH. The four counties that
contain half of all medical homes account for less than 30% of the total Medicaid population. Medicaid’s
enrollment structure and distribution of medical homes provides an opportunity to conduct a ‘natural
experiment’ to analyze whether longer travel distances and times to providers determines why the effects of
some PCMH innovations are often muted. Using a difference-in-difference design, this study will examine
whether the longer travel distances and times to care decreases observed differences in avoidable emergency
department (ED) visits and avoidable inpatient hospitalizations. We will extend this analysis to minorities as
well as populations living in racially segregated neighborhoods to determine if distance effects represent a
higher burden to specific patient groups. Administrative data will be derived from a combination of Medicaid
claims data for recipients that were consecutively enrolled from 2016 to 2018, street network data, and
American Community Survey, which will be used to build socioeconomic and neighborhood segregation
indices. The study analyzes accessibility thresholds that are already incorporated into MMC primary and
specialty care contracts as a mechanism from which to recommend specific standards for PCMHs. Regression
analyses will explore the relationship between travel times and distances on avoidable ED and inpatient visits
by comparing PCMH enrollees to Medicaid recipients who have never entered into the PCMH program,
examining the association between moderators (e.g., neighborhood segregation) and mediators (e.g., primary
care quality) with proximity to preventive care. Findings will have relevance to current MMC network adequacy
policy reform effort...

## Key facts

- **NIH application ID:** 10004638
- **Project number:** 5R03HS026263-02
- **Recipient organization:** UNIVERSITY OF SOUTH CAROLINA AT COLUMBIA
- **Principal Investigator:** Nathaniel Bell
- **Activity code:** R03 (R01, R21, SBIR, etc.)
- **Funding institute:** AHRQ
- **Fiscal year:** 2020
- **Award amount:** $49,998
- **Award type:** 5
- **Project period:** 2019-09-01 → 2022-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10004638

## Citation

> US National Institutes of Health, RePORTER application 10004638, Effect of the patient-centered medical home on geographic and racial disparities in health care access (5R03HS026263-02). Retrieved via AI Analytics 2026-06-08 from https://api.ai-analytics.org/grant/nih/10004638. Licensed CC0.

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