Introduction
- Ostrom Q.T.
- Gittleman H.
- Kruchko C.
- Barnholtz-Sloan J.S.
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- Wing J.J.
- Levine D.A.
- Ramamurthy A.
- Reider C.
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- Schwartz F.
- Ruhil A.
- Denham S.
- Shubrook J.
- Simpson C.
- Boyd S.L.
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- Halverson J.A.
- Barnett E.
- Casper M.
Perhaps most notably, a substantial portion of southern Appalachia is included in the ‘stroke belt,’ which is a long-studied geographic phenomenon of particularly high rates of stroke incidence and mortality in the southeastern U.S.
- Casper M.L.
- Wing S.
- Anda R.F.
- Knowles M.
- Pollard R.A.
Strokes are linked to other neurological disorders, including dementia and cognitive decline,
- Kuźma E.
- Lourida I.
- Moore S.F.
- Levine D.A.
- Ukoumunne O.C.
- Llewellyn D.J.
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so the high rates in the southeast and Appalachia may be particularly burdensome on population neurological health in these areas. Detrimental modifiable factors and clinical characteristics, such as poor diet, smoking, low levels of physical activity, obesity, hypertension, and insufficient sleep, are common in Appalachian populations and may be driving the noted burden of neurological disorders in the region.
- Grandner M.A.
- Smith T.E.
- Jackson N.
- Jackson T.
- Burgard S.
- Branas C.
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- Sabia S.
- Fayosse A.
- Dumurgier J.
- et al.
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- Fang J.
- Wheaton A.G.
- Ayala C.
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- Cardarelli K.
- Westneat S.
- Dunfee M.
- May B.
- Schoenberg N.
- Browning S.
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- Lutfiyya M.N.
- Chang L.F.
- Lipsky M.S.
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- Parks S.E.
- Housemann R.A.
- Brownson R.C.
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- Howard V.J.
- McDonnell M.N.
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- Pugazhenthi S.
- Qin L.
- Reddy P.H.
Rates of neurological disorders are also expected to increase over time in the U.S. without equal increase in providers, indicating a potential shortage of neurological care providers nationwide.
- Dall T.M.
- Storm M.V.
- Chakrabarti R.
- et al.
Any shortage of neurologists in Appalachia may further complicate efforts to reduce regional neurological disorder disparities. Within the last decade, telehealth has emerged as a new strategy to combat shortages of neurology providers in Appalachia, yet barriers persist due to insufficient access to internet/internet-connected devices and limited digital literacy, among others.
- Strowd R.E.
- Strauss L.
- Graham R.
- et al.
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- Saadi A.
- Mendizabal A.
- Mejia N.I.
Overcoming these barriers via policymaking and public health campaigns will be critical for expanding Appalachian teleneurology capabilities.
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- Behringer B.
- Friedell G.H.
residents of Appalachia not only have exceptional difficulty accessing primary and specialist care, but also have poorer health outcomes than other areas of the U.S.
- Behringer B.
- Friedell G.H.
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Factors such as socioeconomic deprivation, hospital closures, lower supply of healthcare workers, topography, low education levels, adverse health beliefs, poor health literacy, and urbanization commonly are cited as factors contributing to healthcare access disparities in the region.
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- Lengerich E.J.
- Tucker T.C.
- Powell R.K.
- et al.
Access disparities for both primary and specialist care have been repeatedly identified and linked to poorer health outcomes in Appalachia,
- Behringer B.
- Friedell G.H.
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- Donohoe J.
- Marshall V.
- Tan X.
- Camacho F.T.
- Anderson R.T.
- Balkrishnan R.
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- Donohoe J.
- Marshall V.
- Tan X.
- Camacho F.T.
- Anderson R.
- Balkrishnan R.
but literature exploring access to neurological care in the region is comparatively sparse.
- Lin C.C.
- Callaghan B.C.
- Burke J.F.
- et al.
This is particularly true for examination of spatial access to care, which is a sub-category of healthcare accessibility specifically referring to the ability of a population in a given area to physically reach health services.
- Apparicio P.
- Gelb J.
- Dubé A.S.
- Kingham S.
- Gauvin L.
- Robitaille É.
Spatial accessibility is an important piece of the broader access to care continuum, along with health insurance coverage, timeliness of care, and a capable healthcare workforce.
Topic: access to care.
Some studies have noted geographic variations and fluctuating densities of neurological care in the U.S.,
- Dall T.M.
- Storm M.V.
- Chakrabarti R.
- et al.
,
- Lin C.C.
- Callaghan B.C.
- Burke J.F.
- et al.
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- van der Goes D.N.
- Ney J.P.
- Garrison L.P.
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- Minden S.L.
- Hoaglin D.C.
- Hadden L.
- Frankel D.
- Robbins T.
- Perloff J.
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- Seabury S.
- Bognar K.
- Xu Y.
- Huber C.
- Commerford S.R.
- Tayama D.
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- Kalkbrenner A.E.
- Daniels J.L.
- Emch M.
- Morrissey J.
- Poole C.
- Chen J.C.
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- Giacobbe A.
- Au K.L.K.
- Nguyen O.T.
- et al.
but none have 1) integrated robust geographic access-specific measures to determine disparities in accessibility or 2) examined accessibility for small areas (e.g., census tracts). The Appalachian region is an ideal candidate for deeper study of neurological care spatial accessibility due to the high burden of neurological disease and the previously identified disparities in access to both primary and specialized care.
In this study, we used a comprehensive physician location dataset to construct neurological care spatial accessibility measures for all census tracts in the 13 states with Appalachian counties. We aimed to compare neurologist spatial access in Appalachian census tracts to spatial access in non-Appalachian census tracts and to identify fine scale localities where intervention campaigns could be targeted. Our overarching objectives were to provide direct evidence of neurological care spatial accessibility disparities in the Appalachian region and to assist in pinpointing small areas where policies and interventions may have the largest impact.
Results
Physician specialty data report: active physicians with a U.S. Doctor of medicine (U.S. MD) degree by specialty, 2015.
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2020 Insights report.
Neurologist SPAR averages in the 13-state study area of both Appalachian and non-Appalachian tracts closely matched the average of the entire nation (1.0), where the mean study area SPARs for 2SFCA, E2SFCA, and 3SFCA were 1.003, 1.102, and 1.035, respectively. In comparison to the maximum 2SFCA (2.553) and E2SFCA (2.883) SPARs, the maximum SPAR for 3SFCA was much higher (7.180), which is likely due to the 3SFCA spatial impedance function placing more emphasis on nearby physicians. SPARs for neurologists were significantly lower in Appalachian tracts compared with non-Appalachian tracts, with mean differences of −0.252 or −25.2% (p Fig. 1 shows the strong effect that the selected access method has on resulting measures, where integration of distance decay (panel B) and spatial impedance (panel C) substantially modulate SPARs, particularly in reducing the likely overestimation of access seen in the 2SFCA method (panel A).

Fig. 1Jenks natural breaks maps of two-step floating catchment area (A), enhanced two-step floating catchment area (B), and three-step floating catchment area (C) spatial access ratios for neurological care (N = 24,610). Red denotes areas with poorer spatial access to neurologists and blue denotes areas with better spatial access to neurologists. The bolded and outlined area is the boundary of Appalachia, as classified by the Appalachian Regional Commission.
Table 1Census-tract level neurologist spatial access ratio descriptive statistics by rural urban commuting area codes and area deprivation quintile (n = 24,610 tracts).
Table 2Census tract neurologist spatial access ratio averages by rural-urban commuting area codes and status as Appalachian (n = 6169) or non-Appalachian (n = 18,441) tract (total N = 24,610 tracts).
Bold: Welch t-test significance <0.05.
Table 3Census tract neurologist spatial access ratio averages by rural-urban commuting area codes, area deprivation, and status as Appalachian (n = 6169) or non-Appalachian (n = 18,441) tract (total N = 24,610 tracts).
Bold: Welch t-test significance <0.05.

Fig. 2Appalachian census tract neurologist spatial accessibility intervention areas (N = 937). Intervention areas include those tracts existing in the lowest natural breaks category of three-step floating catchment area spatial access ratios (≤0.4022) and with the following 2010 rural-urban commuting area codes: 1, 2, and 10.
Discussion
,
- Donohoe J.
- Marshall V.
- Tan X.
- Camacho F.T.
- Anderson R.T.
- Balkrishnan R.
,
- Donohoe J.
- Marshall V.
- Tan X.
- Camacho F.T.
- Anderson R.
- Balkrishnan R.
,
- Lane N.M.
- Lutz A.Y.
- Baker K.
- et al.
this is the first examination of spatial access to neurological care for the Appalachian region. More broadly, though other studies have identified geographic variation in neurological care across the U.S.,
- Dall T.M.
- Storm M.V.
- Chakrabarti R.
- et al.
,
- Lin C.C.
- Callaghan B.C.
- Burke J.F.
- et al.
,
- van der Goes D.N.
- Ney J.P.
- Garrison L.P.
,
,
- Minden S.L.
- Hoaglin D.C.
- Hadden L.
- Frankel D.
- Robbins T.
- Perloff J.
,
- Seabury S.
- Bognar K.
- Xu Y.
- Huber C.
- Commerford S.R.
- Tayama D.
,
- Kalkbrenner A.E.
- Daniels J.L.
- Emch M.
- Morrissey J.
- Poole C.
- Chen J.C.
this is also the first study to directly compute spatial access to neurologist measures for an entire U.S. region. We revealed that urban and rural status are more important drivers of neurologist spatial access than socioeconomic status, as ADI categories had weaker effects on SPARs than RUCA codes when stratifying by ADI and RUCA code. Furthermore, we found that in the most urban and rural areas, the differences in SPARs between Appalachian and non-Appalachian tracts were most stark, which suggests that neurologist access disparities are not only problematic in rural Appalachia, but also in Appalachian metropolitan areas. Though specialist physicians are more frequently located in urban areas,
- Bhavaraju N.
- Nanni J.
- Carlson C.
- Sholk J.
- Peterson K.
- Smith L.
our analysis indicates that Appalachian urban areas, such as Knoxville, TN; Greenville, SC; and Charlestown, WV have substantially poorer spatial access to neurologists than non-Appalachian metro areas. Though there is a lack of direct empirical work as to why neurologist access may be lower specifically in urban Appalachia, potential reasons include difficulty recruiting specialty physicians due to limited budgets of state funding-dependent hospital/academic departments and higher numbers of uninsured patients, as six of the thirteen Appalachian states have opted out of Medicaid expansion. Lower health insurance coverage combined with cultural attitudes in Appalachia may be resulting in a potential cascade effect of reduced specialist care-seeking behavior, lower demand for specialist services, and correspondingly, fewer specialist services and physicians.
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- Starcher R.W.
- Geurin L.
- Shannon L.
- Whitley A.
Medicaid expansion in Alabama, Georgia, Mississippi, North Carolina, South Carolina, and Tennessee may improve urban access to care in these Appalachian states. Beyond tabulating access disparities, our mapping results provide actionable, fine-scale disparity target areas, where policies and intervention campaigns can be directed for highest impact. These maps have the potential to be broadly useful to policymakers, public health practitioners, and clinicians. Overall, our results suggest that basic measures of socioeconomic deprivation and rurality are insufficient to describe access to neurological care.
- Hatcher-Martin J.M.
- Adams J.L.
- Anderson E.R.
- et al.
The importance and effectiveness of teleneurology in Appalachia specifically is also beginning to be understood,
- Strowd R.E.
- Strauss L.
- Graham R.
- et al.
yet barriers persist, especially among the most marginalized Appalachian groups: older individuals, the non-Hispanic Black population, and those on government insurance. The ‘digital divide’ is well-documented in the Appalachian region,
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- Black D.A.
- Mather M.
- Sanders S.G.
and the disparities seem to translate to teleneurology, where lack of internet, smartphones, and computers have been cited as barriers to care.
- Strowd R.E.
- Strauss L.
- Graham R.
- et al.
Policies to increase access to these technologies among marginalized Appalachian populations, such as the recent infrastructure law passed by the U.S. congress,
may help ease barriers identified. Other policy solutions could increase the supply of neurologists serving Appalachia: 1) the recent revision of Conrad 30 ARC J-1 visa waiver policies to include foreign specialist physicians in addition to foreign primary care providers and 2) expansion of domestic medical graduate loan forgiveness programs to include Appalachian specialist physicians.
- Pathman D.E.
- Konrad T.R.
- King T.S.
- Taylor Jr., D.H.
- Koch G.G.
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- DeBolt C.L.
- Brizendine C.
- Tomann M.M.
- Harris D.A.
ARC J-1 visa waiver policies were changed in 2019 to include specialist physicians,
(p30) but the effects are not yet clear. Domestic medical graduate loan repayment/forgiveness programs for Appalachia are typically reserved for primary care providers and targeted specifically to healthcare shortage areas.
NHSC Rural Community Loan Repayment Program.
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NHSC State Loan Repayment Program (SLRP).
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Funding by type: loan repayment programs.
As shown in our analysis, neurologist access does not necessarily follow broader physician access/shortage patterns, which further indicates the utility of specialty-specific spatial access measures in formulating loan forgiveness policy. Another recent advancement to address access to neurological care is the proliferation of quick response mobile units to treat acute conditions, commonly known as mobile stroke units (MSUs).
- Parker S.A.
- Bowry R.
- Wu T.C.
- et al.
MSUs contain imaging equipment, laboratory systems, and hospital telemedicine linkage to provide care at the site of emergency.
- Schwindling L.
- Ragoschke-Schumm A.
- Kettner M.
- et al.
Mobile units have potential to improve treatment timeliness of stroke and other acute neurological conditions in areas with poor access to physical neurologist offices. These solutions could be directed to the disparity target areas we identified in Fig. 2. These intervention areas could be further refined for subspecialties within neurology and incorporate other important factors (e.g., broadband internet) that would impact the delivery of the specific intervention. Beyond adjustments in health policy, hospital, and physician-related factors, patient-level educational and intervention campaigns could be directed to disparity areas to reduce the burden of neurological disorders on the Appalachian region. For example, potential avenues include educational campaigns to improve knowledge of stroke symptoms or intervention campaigns targeting primary prevention of adverse health behaviors.
- Donohoe J.
- Marshall V.
- Tan X.
- Camacho F.T.
- Anderson R.T.
- Balkrishnan R.
,
- Wan N.
- Zou B.
- Sternberg T.
,
- McCrum M.L.
- Wan N.
- Lizotte S.
- Han J.
- Varghese T.
- Nirula R.
but are also novel in the context of our application towards neurologist access. In terms of physician locations, the CMS Care Compare data had high coverage of active physicians, where roughly 97% of neurologists are estimated to be captured by the database.
- Ochieng N.
- Schwartz K.
- Neuman T.
Another strength was stratification of our access measures by rurality and ADI, which allowed for more granular examination of where and why access disparities exist. This study also had several limitations, including possible over- or under-estimation of the physician population, inability to fully explore areas of lowest deprivation, use of 2010 distance matrix and population data, use of a Euclidean distance matrix, and the possibility that poor spatial access to neurologists was simply measuring poorer overall access to physicians. CMS Care Compare physician data may also have over- or underestimated the number and/or density of neurologists in the study area. Because the data are estimated to capture roughly 97% of neurologists,
- Ochieng N.
- Schwartz K.
- Neuman T.
a slight undercount is possible. Other ‘comprehensive’ physician datasets by the AMA and CMS face similar issues with cataloging of physicians,
- DesRoches C.M.
- Barrett K.A.
- Harvey B.E.
- et al.
indicating a lack of better options in addition to the noted high coverage of Care Compare. Also, we included all physician practice locations, as no variable exists in Care Compare by which to restrict to primary practice location, which could have overestimated physician density in certain areas. We used nationwide quintiles for better representation of the true area socioeconomic deprivation of the study area. Only a single tract in the study area existed in the lowest socioeconomic deprivation quintile, which resulted in NAs in our tabulated ADI results. However, using study area-specific quantiles would have underestimated the widespread socioeconomic deprivation in Appalachia, indicating that nation-based ADI quantiles were optimal. We used 2010 distance matrix and population data due to availability and accuracy. In a supplementary analysis of 2010–2019 population change, we found that there was little concern for differential misclassification (Supplementary Materials). Euclidean distance matrices tend to overestimate access to care, particularly for urban areas, as they do not account for the complexity of road networks and other transit modalities, such as urban rail. Although we acknowledge that it would be ideal to account for complex transportation matrices, this requires exponentially more computational and memory requirements, which was not feasible for a census tract-level analysis. Future work may consider using advanced routing methods to build more representative travel matrices. In addition, for 82 or 0.33% of census tracts in the study area, RUCA codes were unavailable. For the 82 missing values, 78 were non-Appalachian tracts, 4 were Appalachian, and overall SPARs were close to 1 for each of the FCA methods. Due to only a small proportion of missing values, significant differential effects due to missingness were exceedingly unlikely. Finally, our supplementary construction of a geographic access measure for primary care providers displayed that our neurologist SPARs were not simply identifying areas with poor overall spatial access to providers (Supplementary Fig. S3). Though there was moderate to strong Spearman correlation between neurologist and primary care provider SPARs, visual inspection showed substantial differences. For example, SPARs for primary care providers in Appalachian metro areas, such as Knoxville, TN and Charleston, WV were substantially higher than SPARs for neurologists in the same areas, revealing the utility of directly studying spatial access to neurologists.
This study demonstrated the significant disparities in geographic access to neurological care in the Appalachian region. Our geographic access measures highlight that access to neurologists cannot be solely defined by rural/urban location or socioeconomic status. Future intervention studies attempting to address disparities in neurological care access should consider incorporating spatial access measures to target areas of greatest need.