Journal Article

ATTACHMENT – F: American Journal of Preventive Medicine article

Health Department Clinics as Pediatric
Immunization Providers
A National Survey
Jeanne M. Santoli, MD, MPH, Lawrence E. Barker, PhD, Bridget H. Lyons, MPH, Nisha B. Gandhi, MPH,
Cindy Phillips, MSW, MPH, Lance E. Rodewald, MD
Objectives:

To describe a national sample of health department immunization clinics in terms of
populations served, patient volume trends, services offered, and immunization practices.

Methods:

Telephone survey conducted with health departments sampled from a national database,
using probability proportional to population size.

Results:

All (100%) 166 sampled and eligible clinics completed the survey. The majority of pediatric
patients were uninsured (42%) or enrolled in Medicaid (34%). Most children (69%) and
adolescents (70%) were referred to the health department, with only 12% using these
clinics as a medical home. A number of clinics (72%) reported recent increases in
adolescents served. Less than 25% of clinics offered comprehensive care, 47% conducted
semiannual coverage assessments, and 76% and 38% operated recall systems for children
and adolescents. Storage of records in an electronic database was common (83%).

Conclusions: Although the majority of these clinics do not provide comprehensive care, they continue
to serve vulnerable children, including adolescents, Medicaid enrollees, and the uninsured, and may represent the main contact with the healthcare system for such patients.
Because assuring the immunization of these children is essential to their health and the
health of our nation as a whole, this immunization safety net must be preserved.
Experience implementing key recommendations such as coverage assessment and feedback as well as reminder or recall may enable health department staff to assist private
provider colleagues. Further research is needed to investigate how patient populations,
services offered, and immunization practices vary by different clinic characteristics.
Medical Subject Headings (MeSH): immunization, pediatrics, public sector (Am J Prev
Med 2001;20(4):266 –271) © 2001 American Journal of Preventive Medicine

Introduction

R

outine childhood immunization is implemented as a shared responsibility among public
health departments, other publicly funded clinics, and private providers. Public health department
clinics serve approximately one sixth of the nation’s
infants and toddlers1 and are the second most common
source of immunizations for this age group. Although
sizable, the current proportion of U.S. children immuFrom the National Immunization Program (Santoli, Barker, Lyons,
Rodewald), and the Epidemiology Program Office (Gandhi), Centers
for Disease Control and Prevention, Atlanta, Georgia; and National
Association of County and City Health Officials (Phillips), Washington, District of Columbia
Nisha Gandhi is currently affiliated with the State Immunization
Branch, California Department of Human Services, Berkeley, California.
Address correspondence and reprint requests to: Jeanne M. Santoli, MD, MPH, National Immunization Program, Centers for Disease
Control and Prevention, 1600 Clifton Road NE, Mailstop E-52,
Atlanta, GA 30333. E-mail: [email protected].

266

nized in health department clinics represents a decrease from a decade ago when half of all children were
immunized in the public sector.2 Today, health department clinics frequently serve as safety-net immunization
providers for children whose families cannot afford the
cost of immunizationss and those without an established relationship with a primary care provider.3–5
Health department clinics have been the target of
numerous interventions to raise immunization coverage levels.6 As a result, much has been learned about
the effect of interventions in this setting. Yet relatively
little is known about the extent to which recommended
immunization practices are implemented. This contrasts sharply with the large number of studies conducted to assess immunization practices among private
providers.7–13
Although national studies14,15 have characterized local health department activities, expenditures, and
jurisdictions in general, little information is available
about the immunization activities supported by these

Am J Prev Med 2001;20(4)
0749-3797/01/$–see front matter
© 2001 American Journal of Preventive Medicine • Published by Elsevier Science Inc.
PII S0749-3797(01)00299-9

ATTACHMENT – G: American Journal of Preventive Medicine article
health departments. We report on a cross-sectional
survey of a national sample of local health department
clinics that describes population served, perceived
trends in patient volumes, implementation of the Standards for Pediatric Immunization Practices,16 communication with other providers, and billing and managed
care activities.

Methods
This study was reviewed by the Human Subjects Coordinator
at the Centers for Disease Control and Prevention’s National
Immunization Program and was determined to be a nonsensitive evaluation of public health practice exempt from Institutional Review Board review.17

Study Population
The sampling frame for this study was developed from the
1997 database of local public health agencies maintained by
the National Association of County and City Health Officials.
Local public health agencies were eligible to participate if
they operated, directly or by contract, a facility that provided
immunization services. Estimates of the size of the population
served by each agency were obtained from the database
(when available) and were supplemented with 1990 U.S.
Census figures as necessary. These estimates were used to
divide agencies for the study sample into two strata. One
stratum consisted of all agencies serving a population that
exceeded 1.25 million (sampled 100%); the second stratum
consisted of the remaining agencies (sampled by using probability proportional to size of population served).

Data Collection
A letter that explained the study was sent to the health officer
for each public health agency. Follow-up telephone calls were
made to discuss the study, to obtain consent, and to identify
the district immunization clinic manager. In districts with
more than one immunization clinic, the manager of the
largest clinic was selected. Clinic managers were contacted to
arrange a telephone interview; a copy of the instrument was
faxed to the interviewee for review before the interview.
Telephone interviews were conducted between June and
October 1998.
The survey instrument contained approximately 100 questions, most of which were fixed-response questions or were
worded to be answered with a single number. Several openended questions were included as well, with responses later
converted to multi-outcome responses by the authors. Before
data collection, the survey instrument was pilot tested with a
sample of clinic managers (n⫽14); revisions were made to
improve clarity.
Before the start of the interview, respondents were instructed that questions would focus on all pediatric patients
(aged 0 –18 years) unless otherwise indicated. Certain questions were asked separately for children (aged 0 –11 years)
versus adolescents (aged 12–18 years).

Statistical Analysis
For survey items that had a fixed response (e.g., has the
number of children served increased, decreased, or stayed
the same in the past 3 years?), the study goal was to estimate
the population-weighted proportion of clinics that responded
in each possible manner. For survey items that had a single
number as a response (e.g., what is the proportion of patients
who have no insurance?), the study goal was to estimate the
population-weighted mean response. Unless otherwise indicated, results presented are weighted by the population
served.
Population-weighted estimates were obtained by using generalized difference estimators. These estimators allow inferences in populations sampled with unequal probabilities. To
further refine study estimates, one of the authors (LER)
provided prior estimates without knowledge of the survey
responses; this guaranteed that prior estimates were independent of survey results.
In the case of ratios (e.g., proportion of facilities that used
a computerized tracking system among those facilities with a
mechanism to identify patients who are behind in immunization), variances were obtained by using standard linear approximation methods. Approximate 95% confidence intervals (CIs) were defined as (estimate) ⫾ 1.96 {variance}0.5.

Results
Of 167 local public health agencies chosen to participate, 166 had clinics that met eligibility criteria for the
study; one agency was excluded because staff indicated
that no facilities providing immunization services were
operated by that agency. Surveys were completed with
100% of the sampled and eligible clinics. An unweighted breakdown of participating clinics included
31 (19%) located in large urban communities (population ⱖ999,999), 129 (77%) in smaller communities
(population 2,501–999,998), and 6 (4%) in rural communities (population ⱕ2500).

Characteristics of Participating Clinics
Ninety-one percent of clinics were operated directly by
the public health department, and nine percent operated under a contract. Sixty-four percent of clinics were
co-located with a Special Supplemental Nutrition Program for Women, Infants, and Children clinic.

Populations Served
The majority of patients served were reported to be
uninsured (42%, 95% CI⫽39% to 44%) or enrolled in
Medicaid (34%, 95% CI⫽32% to 37%), and clinics
reported an average of 24% (95% CI⫽21% to 26%) of
patients who were commercially insured. The majority
of children (69%, 95% CI⫽66% to 72%) and adolescents (70%, 95% CI⫽67% to 74%) were referred to the
health department by other providers. The percentage
of pediatric patients for whom the facility was a medical
home was perceived to be low (12%).
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ATTACHMENT – G: American Journal of Preventive Medicine article
immunizations to children and adolescents, respectively, few (21% and 19%) provided comprehensive
primary care.

Immunization Practices

Figure 1. Population-weighted percentages of trends in pediatric patients served over the past 3 years

Data about patient volume trends over the 3 years
before the survey are presented in Figure 1. Although
the percentage of clinics reporting an increase in
children served was similar to the percentage reporting
a decrease in children served, the majority of clinics
(72%, 95% CI⫽67% to 76%) reported serving an
increased number of adolescents. Among clinics reporting an increase in children served, 58% cited
expanded immunization requirements as the most or
second-most important reason. Among clinics reporting a decrease in children served, the most common
first- or second-ranked reasons were the Vaccines for
Children (VFC) program (56%), Medicaid managed
care (39%), and improved insurance coverage (28%).
Among clinics reporting an increase in adolescents
served, the most common first- or second-ranked reasons were the 1996 adolescent recommendations18
(55%), increased school-based screenings (19%), and
the VFC program (16%).

Types of Services Provided
Table 1 summarizes the services provided to children
and adolescents. Clinics were classified as providing
comprehensive primary care if they reported providing
all of the following: comprehensive well care, acute
illness care, acute follow-up care, chronic illness care,
and immunizations. Although 100% and 98% provided

Table 2 illustrates the percentage of clinics that reported implementing selected recommended practices.
Implementation varied by the age of the patient involved, with more clinics reporting certain recommended practices for children than for adolescents.
Although less than half of the clinics reported conducting semiannual coverage assessments (as recommended in the Standards for Pediatric Immunization
Practices), 82% (95% CI⫽77% to 86%) reported conducting these assessments on an annual basis (as required by Senate appropriations language during the
year in which this study was conducted).19

Information Management Activities
Table 3 describes how clinics routinely communicate
with the primary care providers of referred patients.
For children and adolescents, approximately 85% of
clinics reported that they had no routine mechanism to
communicate with other providers or that they relied
on parents to do so. Only 5% (95% CI⫽3% to 8%) of
clinics reported routinely receiving information from
other providers about immunizations given elsewhere.
In terms of record keeping, 55% (95% CI⫽49% to
61%) of clinics reported maintaining immunization
records in a medical chart. Among these clinics, 95%
(95% CI⫽90% to 99%) used a designated immunization summary page within the chart. Most clinics (83%,
95% CI⫽76% to 91%) reported storing immunization
records in a computerized database, and for 78% (95%
CI⫽73% to 83%) of these clinics, the computerized
database was linked with other providers (other health
department sites, private providers, or both).

Billing Practices and Managed Care Participation
Seventeen percent (95% CI⫽14% to 21%) of clinics
reported serving as a primary care provider or gate-

Table 1. Services provided to children and adolescents by local health department clinics

Service

Population-weighted percentage
of clinics providing service
to children (95% CI)

Population-weighted percentage
of clinics providing service
to adolescents (95% CI)

Comprehensive well care
Acute illness care
Acute follow-up care
Chronic illness care
After-hours phone coverage
Comprehensive primary carea

61 (56–66)
26 (23–30)
33 (28–38)
26 (22–30)
27 (23–30)
21 (17–24)

45 (39–51)
23 (19–26)
28 (23–32)
24 (19–28)
23 (19–27)
19 (15–22)

a
Comprehensive primary care is defined as comprehensive well care, acute illness care, acute follow-up care, chronic illness care, and
immunizations for the indicated age group.
CI, confidence intervals.

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Table 2. Immunization practices reported by local health department clinics
Population-weighted
percentage of clinics
reporting practice
(95% CI)

Practice
Conduct semiannual coverage assessments (by computer or manually) (14)a
Operate a tracking system to identify patients behind in immunization (12)
Children
Adolescents
Operate a reminder system (12)
Children
Adolescents
Operate a recall system (12)
Children
Adolescents
Check immunization status at health maintenance and acute illness visits (4)
Hold routine weekend or evening sessions (1)
Do not require physical examinations for routine immunizations (2)
Do not require appointments for immunizations (2)
Children
Adolescents
Routinely administer up to four simultaneous injections (8)

47 (41–52)
82 (79–85)
56 (51–62)
69 (64–74)
42 (37–47)
76 (71–80)
38 (33–43)
87 (80–93)
59 (54–64)
96 (95–97)
94 (91–96)
94 (91–96)
97 (95–99)

a
Standard (from the Standards for Pediatric Immunization Practices16) on which practice is based is listed beside the practice in (bold).
CI, confidence intervals.

keeper (enrolled provider) for a managed care organization. Thirty-one percent (95% CI⫽27% to 36%) of
clinics reported billing managed care organizations for
children who were referred, and thirty-one percent
(95% CI⫽26% to 35%) reported billing for referred
adolescents. Billing Medicaid was more common: 94%
(95% CI⫽88% to 100%) of clinics billed Medicaid for
assigned pediatric patients and 64% (95% CI⫽59% to
69%) for referred pediatric patients.

Discussion
The Institute of Medicine (IOM) recently reviewed the
roles and responsibilities of the states and of the federal
government in supporting immunization programs and
services.20 As part of this effort, the IOM developed a
conceptual model of the six fundamental roles of the
nation’s immunization system: (1) assure adequate
purchase of vaccine, (2) assure access to vaccine by
public sector when private sector services are not
adequate, (3) control and prevent infectious disease,

(4) conduct surveillance of immunization coverage,
(5) sustain and improve coverage levels, and (6) use
primary care and public health resources efficiently in
achieving national immunization goals. This study,
although not designed to evaluate how well local health
department immunization clinics meet the roles outlined by the IOM, provides descriptive information
relevant to roles two and five—the provision of direct
service delivery in the public sector and experience
with recommended practices to improve immunization
coverage levels.
The study has some important strengths and limitations. Strengths include the sampling frame, which
contained a nearly exhaustive listing of all local public
health agencies within the United States, and the 100%
participation rate. Both factors maximize the likelihood
that data collected were representative and generalizable. Limitations are several. First, survey responses
were not independently validated. Second, the sample
for this study was chosen to be nationally representative, resulting in insufficient power to make any within-

Table 3. Communication with primary care providers of vaccinated children and adolescents

Procedure

Population-weighted
percentage of clinics
using this procedure for
children
(95% CI)

Population-weighted
percentage of clinics
using this procedure
for adolescents
(95% CI)

Other providers not routinely notified
Parent asked to notify other provider
Letter or postcard sent to provider
Fax notification sent to provider
Telephone call to provider

10 (7–13)
74 (69–78)
14 (10–18)
2 (0–4)
0 (0–1)

11 (8–14)
74 (72–75)
13 (9–17)
0a
0 (0–1)

a

Data do not support construction of confidence interval (CI).

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ATTACHMENT – G: American Journal of Preventive Medicine article
group comparisons. Finally, in districts with more than
one immunization clinic, only the manager of the
largest clinic was interviewed; thus, differences among
clinics within a single district are not reflected.
Findings from the current study have several noteworthy programmatic implications. Many patients
served in these clinics needed to visit another source(s)
of primary care to receive the full complement of
clinical preventive services because (1) most clinics did
not offer comprehensive primary care, (2) only a few
children considered these clinics to be a medical home,
and (3) most patients were referred. This need for
extra visits creates missed opportunities and is problematic for vulnerable children, such as Medicaid enrollees
or uninsured children, who are already at increased risk
for underutilization of preventive services, including
immunizations.21–23
A number of programs, targeted to vulnerable children and designed to support the receipt of immunizations and other preventive services simultaneously,
are currently in place. Examples include the VFC
program, an entitlement program that provides publicpurchased vaccines for the immunization of certain
groups of eligible children; the Children’s Health Insurance Program, a federal–state partnership that provides comprehensive insurance for children whose families do not qualify for Medicaid; and Medicaid
managed care, established on a state-by-state basis under waivers to Title XIX, which allows states the flexibility to serve Medicaid recipients via managed care
organizations.
Given the existence of these programs, one might ask
why childhood immunizations warrant an additional
health department safety net. There are several reasons. First, it is unlikely that public entitlement and
insurance programs can provide every child with affordable, timely, and consistent access to care. Second,
childhood immunizations protect the public’s health
and are necessary for the control of vaccine-preventable
diseases in this country. Finally, all states have laws that
require immunization for school entry, making it essential that access to immunizations be assured.
Another noteworthy finding is the widespread increase in immunization services provided to adolescents. Reasons cited for higher adolescent patient
volumes included an increased need for services (because of new recommendations and school requirements) as well as the availability of financial support
(including expansion of the recommended age-range
for certain vaccines covered by the VFC program).
These findings suggest that many adolescents do not
have a strong link with a medical home24 and that,
when immunizations are required for school enrollment, adolescents depend on local health departments.
A third noteworthy finding involves implementation
of the Standards for Pediatric Immunization Practices.
Published by the Department of Health and Human
270

Services in 1993, the Standards represent scientific
evidence, expert opinion, and consensus about how to
deliver childhood immunization services.16 In the current study, clinic staff reported inconsistent implementation of the Standards, with certain practices applied
more frequently than others. Practices implemented
most commonly included not requiring a physical
examination or appointment for immunizations,
checking immunization status at all visits, and administering up to four shots simultaneously, all of which
require few additional resources. In contrast, practices
such as the use of reminder or recall, semiannual
coverage assessments, and extended clinic hours, which
require personnel and financial resources, were implemented much less frequently. This finding is consistent
with the fact that federal funding for immunization
delivery infrastructure, which includes support for
health department immunization clinics, has decreased
by more than 50% since 1996.20
Although not strictly comparable because of different time frames and methodology, similar surveys have
been conducted about immunization practices among
private providers. In general, these surveys have found
that relatively few private providers implement recommended office-based immunizations strategies like reminder or recall and coverage assessments. For example, less than 20% of private providers report using a
reminder or recall system in their practice,10,25 and
annual coverage assessments are conducted at only 6%
of practices.26
A fourth important finding is the large number of
clinics that do not bill third-party payers or do not
participate in managed care. This result likely reflects
the history of health department clinics, governmentsupported entities created to serve indigent, uninsured
patients. With the development of public insurance
programs, however, children and adolescents served by
these clinics are increasingly likely to have some form of
insurance coverage. In addition, as managed care organizations, particularly those serving Medicaid recipients, become more prevalent, there is growing opportunity for providers to participate in managed care.
Because of their experience serving high-risk, publicly
insured patients, health department clinics that provide
comprehensive services may be uniquely qualified to
join such networks.
Finally, that the majority of clinics rely on parents to
notify their children’s primary care providers about
immunizations received at health department clinics is
concerning, particularly as the immunization schedule
becomes increasingly complex. Several studies27–29
have demonstrated that parents are often unaware of
their children’s immunization status and rely on providers to inform them when immunizations are needed.
Lack of accurate information about a child’s immunization history is a barrier to immunization,30and relying
on parents to transmit immunization information be-

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tween providers (verbally or by a hand-held shot
record) may exacerbate this barrier. Immunization
registries may be one way to minimize this problem by
consolidating immunization information.31

7.
8.

9.

Implications
Ideally, vaccines should be given as part of comprehensive care. Although most health department clinics do
not provide comprehensive primary care, these clinics
continue to serve vulnerable children, including adolescents, Medicaid enrollees, and the uninsured, and
may represent the main contact with the healthcare
system for such patients. Because assuring the immunization of these children is essential to their health and
the health of our nation as a whole, this immunization
safety net must be preserved. Although budget constraints may make it difficult, the clinics (in collaboration with local and state health departments) may be
able to improve their financial standing by billing
third-party payers for services rendered and by participating as providers in managed care.
These clinics have experience with coverage assessment and feedback, with reminder or recall, and with
the use of electronic immunization records. This experience places health department staff in a good position
to assist local private provider colleagues in implementing these quality improvement activities.
These findings raise important questions about differences in practices among subgroups, such as urban
clinics vs. rural clinics; clinics that participate in immunization registries vs. clinics that do not; clinics that bill
third-party payers vs. clinics that do not, which deserve
investigation. This study, although it lacks power to
make such comparisons with precision, provides valuable information for planning such an investigation.

10.

11.

12.

13.
14.

15.

16.
17.
18.

19.

20.
21.

22.

23.

Presented in part before the Ambulatory Pediatric Association; San Francisco, California; May 1999.

24.

25.

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