NCHS Data Brief ■ No. 65 ■ July 2011

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics

Community Health Centers: 

Providers, Patients, and Content of Care

Esther Hing, M.P.H.; and Roderick S. Hooker, Ph.D.

Key findings

Data from the National 

Ambulatory Medical Care 

Survey, 2006–2008

•	 In 2006–2008, the majority

of community health center

(CHC) visits were made by

Medicaid-insured or uninsured

patients.

•	 Physicians delivered care

at 69% of CHC visits, nurse

practitioners (NPs) at 21%

of visits, physician assistants

(PAs) at 9% of visits, and

certified nurse midwives

(CNMs) at 1% of visits.

•	 NPs and CNMs saw a higher

percentage of female patients

aged 18–44 than did physicians

or PAs. Physicians were more

likely than NPs to see patients

aged 45 and over, both male

and female. PAs were more

likely than NPs to see males

aged 45 and over.

•	 A higher percentage of NP

and PA visits included health

education and counseling

services than did physician

visits. A lower percentage of

CNM visits included prescribed

medications or immunizations.

For more than 40 years, community health centers (CHCs) have provided

primary care and behavioral and mental health services in medically

underserved communities, regardless of a patient’s ability to pay (1). In

2001, the government launched the Federal Health Center Growth Initiative,

providing funds over 5 years to increase by 60% the number of patients served

in 1,200 communities. As the number of CHCs has expanded, demand for both

physician and nonphysician practitioner services has increased (2). This report

compares patient and encounter characteristics across the different types of

providers seen at CHC visits during a 3-year period, 2006–2008.

Keywords: physician assistants • nurse practitioners • nurse midwives

Who visits CHCs?

•	 During 2006–2008, CHCs averaged 31.1 million visits annually (3,4).

The majority of visits to CHCs (55%) were made by patients who were

    

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NCHS Data Brief ■ No. 65 ■ July 2011

■  2  ■

poor or publicly insured [41% Medicaid or State Children’s Health Insurance Program

(SCHIP) and 14% uninsured] and by patients under age 45 (64%) (Figure 1). About onethird of CHC visits (32%) were by patients of black or other minority racial groups, and

one-third (33%) were by Hispanic or Latino patients.

•	 Comparable percentages of visits to office-based physicians with the same visit

characteristics were significantly lower: 14% of visits to office-based physicians were made

by Medicaid and SCHIP (10%) or uninsured (4%) patients, 45% by patients under age 45,

16% by patients of black or other minority racial groups, and 12% by Hispanic or Latino

patients (data not shown).

Who provides care at CHC visits, and who visits these providers? 

•	 During 2006–2008, 69% of CHC visits were to physicians, 21% to NPs, 9% to PAs, and

1% to CNMs (Table 1). Only 3% of visits involved both a physician and a nonphysician

practitioner (data not shown).

•	 NPs (36%) and CNMs (87%) saw a higher percentage of female patients aged 18–44 than

did physicians (25%) or PAs (22%).

•	 Physicians were more likely than NPs to see patients aged 45 and over, both male and

female. PAs were more likely to see males aged 45 and over (19%) than were NPs (8%).

•	 A lower percentage of patients with one or more chronic conditions visited NPs (39%) than

visited physicians (52%) and PAs (58%), largely because of the younger ages of patients

seen by NPs.

•	 Physicians (72%) and PAs (72%) served as the patient’s primary care provider more

frequently than NPs (58%).

Table 1. Percent distribution of community health center visits, by selected characteristics and provider type: 

United States, 2006–2008

Selected characteristic Physician Physician assistant Nurse practitioner Nurse midwife

Total 100 100 100 100

Sex and age (years):

 Female, under 18 14 12 18 7

 Female, 18–441–3 25 22 36 87

 Female, 45 and over2 24 25 17 *

 Male, under 18 14 11 13 *

 Male, 18–44 9 12 8 –

 Male, 45 and over2,3 15 19 8 –

One or more chronic 

conditions reported2,3 52 58 39 *18

Serves as patient’s 

primary care provider2,3 72 72 58 *42

* Estimate does not meet standards of reliability or precision.

– Quantity zero. 1

Differences between nurse midwife and physician, and between nurse midwife and physician assistant, are statistically significant. 2

Difference between nurse practitoner and physician is statistically significant. 3

Differences between nurse practitioner and physician assistant are statistically significant. 

NOTES: Overall, 69% of visits were to physicians, 21% to nurse practitioners, 9% to physician assistants, and 1% to nurse midwives. Percentages may not add

to 100 because of rounding.

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey. 
NCHS Data Brief ■ No. 65 ■ July 2011

■  3  ■

Why do patients visit different types of providers? 

•	 As assessed by the health care provider, 37% of CHC visits were for a new problem, 29%

were for a chronic problem, 31% were for preventive care, and 3% were for other reasons.

•	 PAs treated a higher percentage of new problems (45%) than did physicians (36%)

(Figure 2).

•	 Physicians (31%) and PAs (36%) had a higher percentage of visits for chronic conditions

than did NPs (21%).

•	 The vast majority of visits to CNMs (82%) were for preventive care. A much lower

percentage of visits to physicians (30%), PAs (17%), and NPs (38%) were for preventive

care.

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NCHS Data Brief ■ No. 65 ■ July 2011

■  4  ■

Do different types of providers deliver different services? 

•	 A higher percentage of visits to NPs (53%) and PAs (54%) included documentation of health

education or counseling services in the medical record, compared with visits to physicians

(42%) (Table 2).

•	 There were no differences among physicians, NPs, and PAs in the percentages of visits in

which drugs or immunizations were prescribed or continued, or laboratory or other types of

tests were ordered or administered.

•	 The percentage of visits to CNMs in which laboratory and other types of tests were ordered

or administered (59%) was higher than the comparable percentage for physicians (46%).

•	 The percentage of visits to CNMs in which drugs or immunizations were prescribed (58%)

was lower than comparable percentages among physicians (79%), NPs (72%), and PAs

(82%).

Table 2. Visits with selected services ordered or provided, by provider type: United States, 2006–2008

Selected service ordered or provided Physician

Physician 

assistant Nurse practitioner Nurse midwife

Percent

Drug or immunization mentioned1 79 82 72 58

Laboratory and other tests2,3 46 49 47 59

Health education service4,5 42 54 53 43

Any imaging 9 *11 8 *19

Nonmedication treatment6 10 15 10 *3

* Estimate does not meet standards of reliability or precision.

1

Differences between nurse midwife and physician, and between nurse midwife and physician assistant, are statistically significant. 2

Laboratory and other tests include scope procedures, biopsy, EKG/ECG, spirometry/pulmonary function test, and other services. 

3

Difference between nurse midwife and physician is statistically significant. 4

Differences between nurse practitioner and physician, and between physician assistant and physician, are statistically significant. 5

Health education services include education about asthma, diet and nutrition, exercise, growth and development, injury prevention, stress management, 

tobacco use and exposure, weight reduction, and other education. 

6

Nonmedication treatment includes complementary and alternative medicine, durable medical equipment, home health care, hospice care, physical therapy, 

radiation therapy, speech and occupational therapy, psychotherapy, other mental health counseling, excision of tissue, orthopedic care, wound care, other 

nonsurgical procedures, and other surgical procedures.

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey. 
NCHS Data Brief ■ No. 65 ■ July 2011

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Summary

This report has presented 2006–2008 National Ambulatory Medical Care Survey (NAMCS)

estimates of visits to CHC practitioners. During this time period, a sizeable portion of visits

(31%) were to PAs, NPs, and CNMs. Within CHCs, NPs and CNMs disproportionately served

young women compared with patients served by physicians, a finding consistent with other

national studies (5). The vast majority of visits to CNMs were for preventive care. PAs had the

highest percentage of visits for new problems. The larger percentage of visits to physicians and

PAs by patients for a chronic condition, compared with visits to NPs, is largely attributable to the

younger age of patients seen by NPs. There were no significant differences in types of services

provided by physicians, NPs, and PAs, with one exception: PAs and NPs were more likely than

physicians to provide or document health education or counseling services at visits.

CHCs serve predominantly low-income patients who are uninsured or who rely on public

insurance (6). The significance of CHCs as sources of care for the uninsured and underinsured

has grown as a result of recent Federally Qualified Health Center (FQHC) expansions and a

worsening economy (6–10). In 2008, visits to CHCs accounted for 14% of all visits to primary

care delivery sites by patients with Medicaid or SCHIP as a primary expected source of payment,

and 12% of visits by uninsured patients (6). Primary care is recognized as an important strategy

for maintaining population health because it is relatively inexpensive, can be more easily

delivered than specialty and inpatient care, and if properly distributed could be effective in

preventing disease progression on a large scale (11). The present report has documented the roles

of nonphysician practitioners in CHCs across the nation from 2006 through 2008. PAs, NPs,

and CNMs have partnered with physicians and nurses to provide care to a wide spectrum of

communities (12,13). The roles of nonphysician practitioners in CHCs are expected to increase

as a result of expanded funding for CHC infrastructure included in the American Recovery and

Reinvestment Act of 2009 (14) and additional funding for CHC expansion and health insurance

coverage for the uninsured included in the Patient Protection and Affordable Care Act of 2010

(15). Monitoring CHC utilization and staffing may provide insight into the changing nature of the

U.S. health care system.

Definitions

Community Health Center (CHC): An outpatient clinic that serves medically underserved

populations (e.g., migrant and seasonal agricultural workers, the homeless, and public housing

residents) (1). CHCs represented in NAMCS include FQHC clinics that receive Section 330

grants under the Public Health Service Act, “look-alike” health centers that meet FQHC

requirements, and federally qualified urban Indian Health Service clinics (1).

Health education services: Include education about asthma, diet and nutrition, exercise, growth

and development, injury prevention, stress management, tobacco use and exposure, weight

reduction, and related topics.

Major reason for visit: The primary reason for the visit as assessed by the health care provider.

“New problem” visits are for conditions with onset of less than 3 months. “Chronic problem”

visits include routine and flare-up visits. “Preventive care” includes visits for routine prenatal and

well-baby care, screening, and insurance and general exams.
NCHS Data Brief ■ No. 65 ■ July 2011

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Nonmedication treatment: Includes complementary and alternative medicine, durable medical

equipment, home health care, hospice care, physical therapy, radiation therapy, speech and

occupational therapy, psychotherapy, other mental health counseling, excision of tissue,

orthopedic care, wound care, other nonsurgical procedures, and other surgical procedures.

Data sources and methods

All estimates are from NAMCS—an annual nationally representative survey of visits to

nonfederal office-based physicians in the United States, conducted by the Centers for Disease

Control and Prevention’s (CDC) National Center for Health Statistics (NCHS). NAMCS uses

a multistage probability sample design involving geographic primary sampling units (PSUs),

physician practices within PSUs, and patient visits within physician practices. Sampled

physicians were selected from the masterfiles of the American Medical Association and the

American Osteopathic Association. Starting in 2006, NAMCS included an additional stratum of

104 CHCs in the sample.

The 2006–2008 NAMCS samples included 312 CHCs within PSUs. Within CHCs, a sample of

up to three CHC providers (physicians, PAs, NPs, or CNMs) scheduled to see patients during the

sample week was selected, and a random sample of visits during an assigned week was selected

for each CHC provider. Among in-scope and eligible CHCs, the overall unweighted four-stage

sampling response rate was 85.5% (86.3%, weighted). Participating CHCs completed a total of

17,128 patient record forms.

Weights that take into account all sample stages, with adjustments for nonresponse, were used to

produce average annual national estimates of physician and nonphysician clinician office visits.

Differences in visit characteristics for nonphysician clinicians and for physicians were analyzed

using Chi-square tests at the p = 0.05 level. To account for the complex sample design during

variance estimation, all analyses were performed using the SUDAAN software package, version

9.0 (RTI International, Research Triangle Park, NC).

The weighted percentage of missing data observed in the data was as follows: patient age and sex

(less than 5%), race (24%), and ethnicity (20%). These data were imputed (3), but the potential

for bias increases as the amount of missing data increases. Therefore, the race and ethnicity data

should be interpreted with caution. As noted in Figure 2, 2% of data were missing for “major

reason for visit” and were included with pre- and postsurgical visits.

About the authors

Esther Hing is with the Centers for Disease Control and Prevention’s National Center for Health

Statistics, Division of Health Care Statistics. Roderick S. Hooker is with The Lewin Group.

References

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NCHS Data Brief ■ No. 65 ■ July 2011

Suggested citation

Hing E, Hooker RS. Community health

centers: Providers, patients, and content of

care. NCHS data brief, no 65. Hyattsville,

MD: National Center for Health Statistics.

2011.

Copyright information

All material appearing in this report is in

the public domain and may be reproduced

or copied without permission; citation as to

source, however, is appreciated.

National Center for Health 

Statistics

Edward J. Sondik, Ph.D., Director

Jennifer H. Madans, Ph.D., Associate 

Director for Science

Division of Health Care Statistics

Jane E. Sisk, Ph.D., Director

U.S. DEPARTMENT OF

HEALTH & HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics

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