(2024) 24:519
Bohnhoff et al. BMC Pediatrics
https://doi.org/10.1186/s12887-024-04995-6

BMC Pediatrics

RESEARCH

Open Access

Pediatric subspecialty outreach clinics: reachand impact on access to care
James C. Bohnhoff1,2,3*, Anya Cutler1,2, Sean Hagenbuch4 and Kristen Kurland5

Abstract
Background Recent research highlighting a shortage of pediatric subspecialists in the United States has shownwide variations in the distance from children to the nearest subspecialists but has not accounted for subspecialty
outreach clinics, in which specialists may improve access in rural areas by periodically staffing clinics there. This study
aimed to determine the impact of pediatric subspecialty outreach clinics on the driving times to the nearest pediatricsubspecialists for children in Maine.
Methods This cross-sectional study utilized administrative data on the schedule and location of pediatric subspecialty clinics in Maine in 2022 to estimate the driving time from each ZIP-code tabulation area to the nearest subspecialist, with and without the inclusion of outreach clinics. Using 2020 census data, we calculated the median and interquartile ranges of driving times for the state’s overall child population, as well as for children living in urban and rural
areas.
Results Of 207,409 individuals under 20 years old in Maine, 68% were located closer to an outreach location
than to a clinical hub. Across the seven subspecialties offering outreach clinics, outreach clinics decreased mediandriving times to the nearest pediatric subspecialist by 5 to 26 minutes among all children, and by 16 to 46 minutes
among rural children.
Conclusions Pediatric subspecialty outreach clinics can substantially reduce the driving time to the nearest pediatric subspecialist , especially for children living in rural areas. The use of outreach clinics should be accounted
for in research describing the geographic access or barriers to care. Expanding the number of outreach clinics should
be considered by policymakers hoping to improve access.
Keywords Access, Pediatrics, Rural Health, Health Care Disparities, Health Workforce*Correspondence:
James C. Bohnhoff
james.bohnhoff@mainehealth.org
1
Department of Pediatrics, MaineHealth, 1577 Congress St Fl 1, Portland,
ME 04102, USA
2
Center for Interdisciplinary Population and Health Research,
MaineHealth Institute for Research. 1, Riverfront Plaza, Westbrook, ME
04092, USA
3
Department of Pediatrics, Tufts University School of Medicine, 136
Harrison Ave, Boston, MA 02111, USA
4
Northern Light Health, 489 State St, Bangor, ME 04401, USA
5
Carnegie Mellon University, College of Fine Arts Building, Suite 201,
Pittsburgh, PA 15213, USA

Background
In its 2023 report, “The Future Pediatric Subspecialist Physician Workforce,” the National Academy of Sciences, Engineering and Medicine warned that the UnitedStates’ subspecialty workforce may be increasingly inadequate, and inadequately distributed, to meet the healthneeds of children [1]. Among families reporting a needfor pediatric subspecialty care in the United States, 24%
report difficulty accessing this care [2]. Children referredto pediatric subspecialists may wait multiple months [3,4] or travel hundreds of miles [5] before reaching care.
Subspecialists are particularly inaccessible for children© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0
International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as longas you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if
you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article orparts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicatedotherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not
permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To
view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.

Bohnhoff et al. BMC Pediatrics(2024) 24:519

in rural areas, [6] in part because of the concentration ofpediatric subspecialists in urban centers [1].
Multiple access strategies with the potential to reduce
geographic barriers to care exist, including telemedicine,electronic consultations, and outreach clinics, in whichsubspecialists travel to secondary sites on an intermittent
basis to provide more accessible care. Outreach clinics inparticular have the potential to improve rural access since
they may be targeted to rural or other areas where care isotherwise limited [7]. However, although electronic consultations and telemedicine have been studied extensively
in recent years, [8–11] comparatively little is known
about outreach clinics in the pediatric setting, including how widely they are used or how much they impact
access [12]. In the most recent (2020) major assessmentof geospatial access to pediatric subspecialty care, Turner
et al. described the national state of children’s access tocare based on their distance to the nearest subspecialists,
the location of which was based on the most recent homeor business address on file with the American Board of
Pediatrics, an approach which does not account for multiple practice locations or outreach clinics [5].
Details regarding the current availability (and ideally,
utilization) of outreach clinics will facilitate more accurate assessments of the true state of geographic accessto pediatric subspecialty care, and may also support
decisions, both at the level of health systems and states,around supporting these potentially costly initiatives.
Here, we utilize administrative data from the two healthsystems providing pediatric subspecialty care in the ruralstate of Maine to describe the frequency of pediatric subspecialty outreach clinics and the impact of these clinics
on driving times throughout the state. We hypothesizedthat outreach clinics would substantially decrease travel
times for children across the state.

Methods
Setting and study design

Maine is the second most rural of the United States,
and also contains geographic barriers to care including
mountains, lakes, and famously jagged coastlines [13, 14].
Two major health systems provide all pediatric subspecialty care in the state. In this cross-sectional analysis,we
obtained from administrators at each system schedulinginformation and street addresses for pediatric subspecialty clinics held by pediatric divisions in 2022, both at
the systems’ “hubs” and at outreach clinic locations. We
did not include any surgical subspecialties or mental
health specialties, which were not administered or scheduled through pediatric divisions in either health system.
Data on the pediatric population in Maine was obtained
from the United States Census Bureau 2020 estimates ofPage 2 of 7

the population of individuals 0–19 years old in each ZIPcode tabulation area (ZCTA) [15].
Calculation of travel times

All analyses were performed in R v4.2.1 [16]. For each
pediatric subspecialty for which there were outreach clinics, we used the gmapsdistance package to calculate theGoogle Maps estimated driving time in minutes (without traffic) from each ZCTA centroid in the state to thenearest “hub” at which the subspecialty provided care.
We also calculated the driving time from each ZCTA
centroid to the nearest clinic location of any kind (hubor outreach). For each ZCTA and subspecialty, we subtracted the driving time to the nearest clinic of any kindfrom the driving time to the nearest hub to calculate thedecrease in driving time attributable to the presence ofoutreach clinics.
Analysis

To assess the overall burden of travel and impact of outreach clinics across the pediatric population in Maine, wecreated population-level distributions of driving times
by weighting the driving times of each ZCTA by thechild population within that ZCTA. For each specialty
we calculated the median and interquartile range (IQR)
of driving times for the child population in the state. In
order to understand how outreach clinics might differently impact children’s access based on their rurality, we
repeated driving time calculations for children residing
in urban (Rural–Urban Commuting Area (RUCA) codes
1–3) and rural (RUCA codes 4–10) [17] areas. Children
in one ZCTA which was not included in RUCA files were
included in overall population travel time calculations,but not in rural or urban calculations.
Ethical considerations and data availability

This study was reviewed by the MaineHealth Internal
Review Board and determined not to be human subjects
research – informed consent was not required. Because
this study was based on administrative data privately
owned by Northern Light Health and MaineHealth, thesedata are not available through the authors. However, thecorresponding author may facilitate a direct data requestfrom the entities above on request.

Results
Outreach clinic locations and frequency

We identified seven subspecialties for which outreachclinics were provided by at least one of Maine’s two
pediatric subspecialty groups (pediatric cardiology, gastroenterology, endocrinology, neurology, genetics, pulmonology, and nephrology). Outreach clinics were heldin 7 locations throughout the state. At locations whereBohnhoff et al. BMC Pediatrics(2024) 24:519

Page 3 of 7

times to the nearest hub were as long as 397 min. 68%
of children (87% of children in rural areas) were closer
to at least one outreach clinic location than to a hub.
The inclusion of outreach clinics decreased the mediandriving time by anywhere from 5 min (from 49 to
44 min, neurology) to 26 min (from 71 to 45 min, pulmonology, Table 2). Among rural children, the inclusion of outreach clinics decreased the median driving
time by anywhere from 16 min (from 70 to 54 min, neurology) to 46 min (from 95 to 49 min, nephrology). The
median and interquartile ranges of the driving times
to the nearest hub and the driving times to the nearest
clinic location of any kind among all children in Maine
and among children in urban and rural areas are illustrated in Fig. 2.

a given subspecialty held an outreach clinic, clinics
occurred a median 11 times (IQR 4.5–23 times) in 2022.
In contrast, subspecialty clinics were scheduled in eachhub at least three days each week (or more than 150 times
in 2022). Data on the locations and frequency of subspecialty outreach clinics is shown in Table 1 and Fig. 1.
Driving time

Of 207,409 children under 20 years old in Maine, 38.9%
were located more than one hour from the nearest
clinical hub. The driving time to the closest clinical hub
was a median 50 min (IQR 37 -72) for all children anda median 70 (IQR 50–95) minutes for children living
in rural areas. For pediatric pulmonology and nephrology (which were only provided at one hub), driving

Table 1 Frequency of clinics held in Maine at clinical hub (A, B) and outreach (a-g) locations in 2022
Clinical hubsA

Outreach clinics
B

a

b

10

6

Cardiology

> 150

> 150

Endocrinology

> 150

> 150

Gastroenterology

> 150

> 150

Genetics

> 150

> 150

> 150

> 150

Nephrology
Neurology
Pulmonology

> 150

10
2

c

d

e

f

g

11

5

1

11

47

11

6

4

22

6

37

1

11

2

25

2

24

2

23

> 150

Fig. 1 Pediatric subspecialty clinical hub and outreach clinic locations in Maine

23
39

19

Bohnhoff et al. BMC Pediatrics(2024) 24:519

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Table 2 Driving time in minutes to nearest pediatric subspecialists among all Maine children
Overall (n = 207,409)a

Urban (n = 93,448)

Rural (n = 113,916)

Clinical Hubs onlyb

With Outreach Clinical Hubs onlyb
Clinicsb

With Outreach Clinical Hubs onlyb
Clinicsb

With
Outreach
Clinicsb

Cardiology

50(37–72)34(23–48)38(23–49)27(20–42)70(50–95)37(28–54)

Endocrinology

49(36–71)34(23–48)38(22–48)27(20–40)69(49–93)41(29–67)

Gastroenterology

49(36–71)34(22–48)38(22–48)27(20–41)69(49–93)39(29–55)

Genetics

48(34–72)34(23–48)35(22–46)26(21–41)69(49–91)39(29–55)Nephrology

71(42–118)46(30–65)45(25–73)42(25–53)95(68–164)49(32–78)

Neurology49(36–72)44(30–61)38(23–48)37(23–47)70(52–93)54(36–80)Pulmonology

71(42–118)45(28–67)45(25–73)38(21–51)95(68–164)53(34–100)

Child population is based on 2022 ACS estimatesa

45 children live in a zip code tabulation area not contained in the RUCA filesbMedian (IQR)

Discussion
Findings and implications

In this study we found that among all children in Maine,
more than two thirds lived closer to an outreach clinic
than to a pediatric specialty hub. The impact of theseclinics varied by specialty and was concentrated amongchildren in rural areas, who were located farthest from
specialty hubs. This illustrates the potential of outreachclinics to improve access and urban–rural access equity.
Within our state, our findings show that children in rural
areas still face significant disparities in geographic accessto care, particularly for specialties (such as pulmonology)
which are only offered at one clinic hub or for specialties(such as neurology) which are offered at relatively few
outreach sites. For other health systems and researchers,
our findings have two important implications: first, theysuggest that current assessments of access to pediatricspecialty care which do not account for outreach clinics may underestimate access, especially in rural areas
where outreach clinics have the greatest impact. Second,
they suggest that outreach clinics should be consideredby health systems and policymakers aiming to improveexisting access to care in rural settings.
The impact of outreach clinics in improving access may
be mitigated by the relative infrequency at which they arescheduled. Of the 25 subspecialty-location combinations,
16 clinics were held 12 or fewer times in 2022, and 10
were held 6 or fewer times. Waiting up to two months forthe next clinic day may not be appropriate for all patients.
In addition, prior research has shown that attendance offirst subspecialty appointments decreases with greaterinterval to scheduled appointment, [4] although the same
may not hold true for return subspecialty visits.
Strengths and limitations

Because the data for this study was collected directlyfrom health systems and not extrapolated from otherdata sources, our data reflects the actual locations andintervals at which care is provided. Because we collected
data from the only two health systems in Maine, our findings are likely to truly reflect the closest subspecialists tochildren throughout the state. There are limitations to
our methods, however. We focus on one state only, andthe potential and realized impacts of outreach clinics inother locations may be different based on the distribution of clinical hubs and the implementation of outreachclinics. We also did not account for travel across statelines, and although the impacts of interstate travel would
likely be minimal in a state with mostly international andcoastal borders, they may significantly decrease the driving time to the nearest specialist in other locations.
The most important limitation of this study is that ourmeasures (on-road driving time to the nearest subspecialty clinic and frequency of subspecialty clinic days)
only capture specific aspects of subspecialist access,which is a rich and multifaceted concept [18]. On-road
driving time is one aspect of geographic access (or barriers) to care, but does not account for variations in
geographic access that might result from public transportation, automobile ownership, or innovations such

Bohnhoff et al. BMC Pediatrics(2024) 24:519

Fig. 2 Driving time to pediatric specialists from ZCTAs in Maine

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Bohnhoff et al. BMC Pediatrics(2024) 24:519

as telemedicine. Similarly, the frequency of clinic days
represents one aspect of availability of care, but may not
capture the actual availability of appointments. We also
did not capture patients’ perceptions of need for care,desire to seek care, ability to pay for care or other aspectsof access. Thus, this study provides only a partial description of access to subspecialty care in the state of Maine. It
does, however, demonstrate that outreach clinics can insome settings substantially impact geographic access tocare, particularly for children in rural areas, and we feel
this is sufficient to recommend the inclusion of outreachclinics in future analyses of access to pediatric subspecialty care. Broader implementation of outreach clinics could further improve geographic access, but might
depend on mechanisms to compensate health systems
for the additional expenses of outreach clinics, which can
include travel time and clinical space. Future research
examining individual patients accessing outreach clinics and the patient experiences and outcomes associatedwith outreach clinics could better justify these costs.

Conclusions
This study found that the pediatric subspecialty outreachclinics in a rural state reduced the driving times to thenearest subspecialty care. These reductions in travel time
were accentuated in rural areas, although this apparent improvement in access may be offset by the relative
infrequency of scheduled outreach clinics compared
to clinical hubs. Outreach clinics should be consideredby policymakers hoping to improve access to care andshould be accounted for in research describing the geographic access or barriers to care.
Acknowledgements
We appreciate the willingness of Northern Light Health and MaineHealth toshare their data for this study.
Authors’ contributions
James Bohnhoff contributed through study conceptualization and design,
data analysis and interpretation, and initial manuscript drafting. Anya Cutler
contributed through data analysis and interpretation, and critical manuscript
review. Sean Hagenbuch contributed through study design, data acquisitionand critical manuscript review. Kristen Kurland contributed through supervision, data interpretation, and critical manuscript review.
Authors’ information
None additional to information displayed on title page.
Funding
Supported by the NCATS [1K12TR004384]. The content is solely the responsibility of the authors and does not necessarily represent the official views of
the NIH. The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation,
review, or approval of the manuscript; or decision to submit the manuscriptfor publication.
Availability of data and materials
The datasets used and/or analyzed during the current study cannot be madeavailable from the corresponding authors but can be requested from theoriginating institutions.

Page 6 of 7

Data Availability
This study was based on administrative data privately owned by Northern
Light Health and MaineHealth, these data are not available through theauthors. However, the corresponding author may facilitate a direct data
request from the entities above on request.

Declarations
Ethics approval and consent to participate
This study was approved by the Institutional Review Board of MaineHealth. We
confirm that all our methods were conducted in agreement with the Declaration of Helsinki. Documentation of consent was not applicable to this study
which relied on administrative data.
Consent for publication
N/A.
Competing interests
The authors declare no competing interests.
Received: 26 March 2024 Accepted: 6 August 2024

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