NCHS Data Brief ■ No. 38 ■ May 2010

u.s. department of health and human services

Centers for Disease Control and Prevention

National Center for Health Statistics

Emergency Department Visitors and Visits: Who Used the 

Emergency Room in 2007? 

Tamyra Carroll Garcia, Amy B. Bernstein, and Mary Ann Bush

Key findings 

• Older adults (aged 75 

and over), non-Hispanic 

black persons, poor persons, 

and persons with Medicaid 

coverage were more likely 

to have had at least one 

emergency department (ED) 

visit in a 12-month period 

than those in other age, race, 

income, and insurance groups.

• Among the under-65 

population, the uninsured were 

no more likely than the insured 

to have had at least one ED 

visit in a 12-month period.

• Persons with Medicaid 

coverage were more likely to 

have had multiple visits to the 

ED in a 12-month period than 

those with private insurance 

and the uninsured.

• ED visits by the uninsured 

were no more likely to be 

triaged as nonurgent than visits 

by those with private insurance 

or Medicaid coverage.

• Persons with and without a 

usual source of medical care 

were equally likely to have 

had one or more ED visits in a 

12-month period.

Since 1996, demand for emergency services in the United States has been 

rising (1). While the number of emergency departments (EDs) across the 

country has decreased, the number of ED visits has increased (1). As a result, 

EDs are experiencing higher patient volume and overcrowding, and patients 

seeking care are experiencing longer wait times (2,3). As national health 

care costs continue to rise and policymakers become increasingly interested 

in ways to make the health care system more efficient, it is important to 

understand the characteristics of those individuals who use EDs—often in 

place of other sources of ambulatory care. 

Keywords: uninsured • National Health Interview Survey • National Hospital 

Ambulatory Medical Care Survey • access to medical care

Emergency room use varies by race/ethnicity, age, and 

family income. 

Percent

Figure 1. Percentage of persons with at least one emergency department visit in a 12-month

period, by selected demographic characteristics: United States, 2007

Total

Age

0–17

18–44

45–64

65–74

75+

Race and Hispanic origin

Hispanic1

Non-Hispanic black

Non-Hispanic white

Percent of poverty level2

Below poverty

100%–<200%

200%–<400%

400%+

0 10 20 30 40 50

1

Persons of Hispanic origin may be of any race. 2

Based on family income and family size and composition using U.S. Census Bureau poverty thresholds. 

NOTES: Error bars indicate 95% confidence intervals. Access data table for Figure 1 at: 

http://www.cdc.gov/nchs/data/databriefs/db38_tables.pdf#1.

SOURCE: CDC/NCHS, National Health Interview Survey.
NCHS Data Brief ■ No. 38 ■ May 2010

■  2  ■

• In 2007, approximately one in five persons in the U.S. population had one or more ED visits 

in a 12-month period (Figure 1). 

• Older adults—those aged 75 and over—were more likely to have had at least one ED visit in 

a 12-month period than people in younger age groups. 

• Non-Hispanic black persons were more likely to have had one or more ED visits in a 12-

month period than non-Hispanic white or Hispanic persons. 

• As family income increased, the likelihood of having one or more ED visits in the past year 

decreased. These income-related differences were more pronounced than those based on age 

or race/ethnicity.

ED use is associated with insurance status, with Medicaid beneficiaries 

being the most likely to have had an ED visit. 

• Among Medicaid beneficiaries under age 65, more than one-quarter of children and nearly 

two in five adults had one or more ED visits in a 12-month period (Figure 2). Medicaid 

beneficiaries were more likely to have had at least one ED visit in a 12-month period than 

persons with private insurance and the uninsured. 

• Among Medicare beneficiaries aged 65 and over, dually eligible persons with Medicaid 

were more likely than those without Medicaid to have had one or more visits to the ED in a 

12-month period.

• Among children and among adults aged 45–64, the uninsured were no more likely than 

those with private insurance to have had at least one ED visit in a 12-month period. 

Figure 2. Percentage of persons with at least one emergency department visit in a 12-month period, by age and 

insurance status: United States, 2007

Age in years

Medicaid Uninsured 1

Private health

insurance

Medicare and

Medicaid

Medicare,

no Medicaid

Percent

0

10

20

30

40

50

0–17 18–44 45–64 65+

1

Includes Children’s Health Insurance Program coverage. 

NOTES: Error bars indicate 95% confidence intervals. Private, Medicaid, and uninsured categories are mutually exclusive. Persons with both private and 

Medicaid coverage are categorized as having private coverage. Access data table for Figure 2 at: 

http://www.cdc.gov/nchs/data/databriefs/db38_tables.pdf#2.

SOURCE: CDC/NCHS, National Health Interview Survey.
NCHS Data Brief ■ No. 38 ■ May 2010

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• Among adults aged 18–44, by contrast, the uninsured were more likely than those with 

private insurance to have had at least one ED visit. 

Frequency of ED use was associated with insurance status, with Medicaid 

beneficiaries being the most likely to have visited the ED multiple times in 

the past year. 

• Approximately 15% of Medicaid beneficiaries under age 65 had two or more ED visits in 

a 12-month period, compared with 7% of the uninsured and 5% of the privately insured 

(Figure 3). 

• The percentage of Medicaid beneficiaries under age 65 with four or more ED visits in a 

12-month period (5%) was higher than the percentage of persons with four or more visits 

among the uninsured (2%) and those with private insurance (1%).

• The uninsured were more likely to have had multiple ED visits in the past year than those 

with private insurance.

Health insurance status was not associated with ED visits being triaged as 

nonurgent. 

• In 2007, 10% of ED visits by persons under age 65 were considered nonurgent.

• ED visits were triaged as nonurgent at similar rates among the uninsured, persons with 

Medicaid coverage, and those with private insurance (Figure 4).

Figure 3. Percentage of persons under age 65 with multiple emergency department visits in a 12-month period, by

insurance status: United States, 2007

Medicaid Uninsured 1

Private health

insurance

Percent

0

10

20

30

40

1 or more visits 2 or more visits 4 or more visits

1

Includes Children’s Health Insurance Program coverage. 

NOTES: Error bars indicate 95% confidence intervals. Private, Medicaid, and uninsured categories are mutually exclusive. Persons with both private and 

Medicaid coverage are categorized as having private coverage. Access data table for Figure 3 at: 

http://www.cdc.gov/nchs/data/databriefs/db38_tables.pdf#3.

SOURCE: CDC/NCHS, National Health Interview Survey.
NCHS Data Brief ■ No. 38 ■ May 2010

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Adults reporting fair or poor health status were the most likely to have used 

the ED. 

• More than one-third of adults aged 18 and over with respondent-assessed fair or poor health 

status had at least one ED visit during the past 12 months, which was more than twice the 

rate for adults reporting very good or excellent health (Figure 5). 

• Within each health status group, the percentage of adults who had at least one ED visit 

varied little across age groups.

Figure 4. Percentage of emergency department visits triaged as nonurgent among persons under age 65, by age and 

expected source of payment: United States, 2007

Uninsured

Medicaid

Private

Age in years

Percent

0 10 20 30 40 50

0–64

0–44

45–64

NOTES: Error bars indicate 95% confidence intervals. Nonurgent visits are those where being seen within 2 to 24 hours is appropriate. Private, Medicaid, and 

uninsured categories are mutually exclusive. Visits with both private and Medicaid sources of payment are categorized as private. No-charge, charity, and 

self-pay visits are categorized as uninsured. Access data table for Figure 4 at: http://www.cdc.gov/nchs/data/databriefs/db38_tables.pdf#4.

SOURCE: CDC/NCHS, National Hospital Ambulatory Medical Care Survey.

Figure 5. Percentage of adults with at least one emergency department visit in a 12-month period, by respondentassessed health status: United States, 2007

Fair or poor

Very good or excellent

Good

Age in years

Percent

0 20 40 60 80 100

18+

18–44

45–64

65+

NOTES: Error bars indicate 95% confidence intervals. Access data table for Figure 5 at: http://www.cdc.gov/nchs/data/databriefs/db38_tables.pdf#5.

SOURCE: CDC/NCHS, National Health Interview Survey.
NCHS Data Brief ■ No. 38 ■ May 2010

■  5  ■

Persons with a usual source of medical care were no less likely to have had 

at least one ED visit than those without a usual source of care. 

• Children and adults under age 65 with and without a usual source of medical care were 

equally likely to have had at least one ED visit (Figure 6). 

• Adults aged 65 and over with a usual source of medical care were more likely to have had 

an ED visit within a 12-month period than those without a usual source of care. 

Summary

EDs provide a critical service to persons in need of immediate, often life-saving, treatment and 

are a major component of the health care system. One fifth of the civilian noninstitutionalized 

population had at least one ED visit in 2007. The percentage of persons with at least one ED visit 

varied according to sociodemographic characteristics and respondent-assessed health status.

Persons with Medicaid coverage were more likely to report at least one ED visit and multiple ED 

visits in a 12-month period than those with private coverage or the uninsured. This finding may 

reflect higher rates of disability and chronic conditions among persons with public insurance, 

including Medicaid, relative to the uninsured (3). However, uninsured persons under age 65 were 

more likely to have multiple ED visits in a 12-month period than those with private insurance. 

The data also show that persons without a usual source of medical care are not more likely to 

have an ED visit than those with a usual source of care, and that uninsured persons are not more 

likely than others to access the ED for nonurgent visits. Future work should focus on untangling 

the complex interactions among the sociodemographic, health status, and health care access 

factors that appear to be associated with visits to the ED.

Figure 6. Percentage of persons with at least one emergency department visit in a 12-month period, by age and usual 

source of medical care: United States, 2007

Usual source of medical care

No usual source of medical care

Age in years

Percent

0 10 20 30 40 50

0–17

18–44

45–64

65+

NOTES: Error bars indicate 95% confidence intervals. Persons who report the emergency department as their usual source of medical care are defined as

having no usual source of care. Access data table for Figure 6 at: http://www.cdc.gov/nchs/data/databriefs/db38_tables.pdf#6.

SOURCE: CDC/NCHS, National Health Interview Survey.
NCHS Data Brief ■ No. 38 ■ May 2010

■  6  ■

Definitions

ED visit: In the National Health Interview Survey (NHIS), respondents were asked the number 

of times they had gone to a hospital emergency room during the past 12 months, including visits 

that resulted in hospitalization, using the following response categories: none, 1, 2–3, 4–5, 6–7, 

8–9, 10–12, 13–15, and 16 or more. In the National Hospital Ambulatory Medical Care Survey 

(NHAMCS), hospital ED visits are sampled, and trained survey staff abstract information on each 

ED visit. 

Percent of poverty level: Reported and imputed family income was grouped into four categories 

based on family income as a percentage of the poverty level. Family income data were missing 

and imputed for 33% of all persons in NHIS in 2007. Poverty level is based on family income, 

family size, and number of children in the family, and, for families with two or fewer adults, the 

age of the adults in the family. For more information, visit the U.S. Census Bureau website at: 

http://www.census.gov/hhes/www/poverty.html. 

Private health insurance: Indicated in NHIS when respondents reported that they were covered by 

any private health insurance—whether they purchased the policy on their own or coverage was 

purchased through an employer or union—at the time of their NHIS interview. Persons with both 

private insurance and Medicaid are categorized as having private insurance. In NHAMCS, private 

insurance was marked as the expected source of payment. When more than one expected source 

of payment was marked along with private, the visit was categorized as private. 

Medicaid: Indicated in NHIS when respondents reported that they were covered by Medicaid, 

state-sponsored health plans, or the Children's Health Insurance Program (CHIP) and did not 

report private insurance at the time of their NHIS interview. In NHAMCS, Medicaid/CHIP was 

marked as the expected source of payment.

Uninsured: Indicated in NHIS when respondents reported that they were not covered by private 

insurance, Medicaid, Medicare, CHIP, state-sponsored or other government-sponsored health 

plans, Medicare, or military health plans at the time of their NHIS interview. A person was also 

defined as uninsured if he or she had only Indian Health Service coverage or a private plan that 

paid for only one type of service, such as accidents or dental care. In NHAMCS, self-pay or no 

charge/charity was marked as the expected source of payment.

Medicare and Medicaid: Indicated in NHIS when respondents reported that they were covered 

by Medicare and Medicaid or state-sponsored health plans at the time of their NHIS interview. 

“Medicare, no Medicaid” is indicated in NHIS when respondents reported that they were covered 

by Medicare and did not report having Medicaid or state-sponsored health plans at the time of 

their NHIS interview. These respondents may have also reported additional types of coverage or 

no additional coverage. 

Nonurgent visit: A visit in which the medical record indicates that patient should be seen within 

120 minutes to 24 hours.
NCHS Data Brief ■ No. 38 ■ May 2010

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Respondent-assessed health status: Assessed in NHIS by asking the family respondent about his 

or her health or the health of a family member: “Would you say ___’s health is excellent, very 

good, good, fair, or poor?”

Usual source of medical care: Assessed in NHIS by asking the respondent: “Is there a place that 

you usually go when you are sick or need advice about your health?” Persons who reported the 

ED as their usual source of care were defined as having no usual source of care.

Data sources and methods

This report uses data from the 2007 NHIS and the 2007 NHAMCS. 

National Health Interview Survey (NHIS) is a continuous, cross-sectional household interview 

survey drawn from all 50 states and the District of Columbia. The main objective of NHIS is to 

monitor the health of the U.S. population through the collection and analysis of data on a broad 

range of health topics. Data are collected through a personal household interview that contains 

Core questions plus Supplements. The Household and Family components of the Core questions 

include information on sociodemographic characteristics, health insurance, basic indicators of 

health status, and utilization of health care services. For this report, data on sociodemographic 

characteristics, health insurance, and respondent-reported health status are based on questions 

asked of family respondents in the Family component of NHIS, and data on ED visits and usual 

source of medical care are based on questions asked in the Sample Child and Sample Adult 

questionnaires. In the 2007 NHIS, the final Sample Child response rate was 76.5% and the final 

Sample Adult response rate was 67.8%. For further information about NHIS, including the 

questionnaire, visit the NCHS website at: http://www.cdc.gov/nchs/nhis.htm.

National Hospital Ambulatory Medical Care Survey (NHAMCS) is designed to collect 

data on the utilization and provision of ambulatory care services in hospital EDs and outpatient 

departments. It is a national, representative sample of visits to the EDs and outpatient departments 

of nonfederal general or short-stay hospitals. Data are also collected on patients’ demographic 

characteristics, expected sources of payment, complaints, diagnostic or screening services, 

procedures, medication therapy, type of providers seen, reason for visit, and diagnoses. NHAMCS 

data on ED urgency in this analysis are restricted to ED visits by persons aged 0–64 where the 

urgency of the visit is known. Visits that were not triaged and visits where urgency was not 

reported are excluded. The percentage of visits that were excluded for these reasons did not differ 

significantly by insurance category, ranging from 15% for visits by persons with Medicaid to 17% 

for visits by the uninsured.

Point estimates and estimates of corresponding variances for this analysis were calculated using 

SUDAAN software (4) to account for the complex sample design of the surveys. All estimates 

shown have a relative standard error less than or equal to 30%. Differences between percentages 

were evaluated using two-sided significance tests at the 0.05 level. Terms such as “higher than” 

and “less than” indicate statistically significant differences. Terms such as “similar” and “no 

difference” indicate that the statistics being compared were not significantly different. Lack of 

comment regarding the difference between any two statistics does not necessarily mean that the 

difference was tested and found to be not significant.
NCHS Data Brief ■ No. 38 ■ May 2010

About the authors

Tamyra Carroll Garcia, Amy B. Bernstein, and Mary Ann Bush are with the 

Centers for Disease Control and Prevention’s National Center for Health 

Statistics, Office of Analysis and Epidemiology.

References

1. Pitts SR, Niska RW, Xu J, Burt CW. National Hospital Ambulatory 

Medical Care Survey: 2006 emergency department summary. National health 

statistics reports; no 7. Hyattsville, MD: National Center for Health Statistics. 

2008. Available from: http://www.cdc.gov/nchs/data/nhsr/nhsr007.pdf.

2. Institute of Medicine. Hospital-based emergency care: At the breaking 

point. Washington, DC: National Academies Press. 2006.

3. Newton MF, Keirns CC, Cunningham R, et al. Uninsured adults presenting 

to U.S. emergency departments: Assumptions vs data. JAMA 300(16):1914–

24. 2008.

4. SUDAAN, release 9.1 [computer software]. Research Triangle Park, NC: 

Research Triangle Institute. 2004.

Suggested citation

Garcia TC, Bernstein AB, Bush MA. 

Emergency department visitors and visits: 

Who used the emergency room in 2007? 

NCHS data brief, no 38. Hyattsville, MD: 

National Center for Health Statistics. 2010.

Copyright information

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the public domain and may be reproduced 

or copied without permission; citation as to 

source, however, is appreciated.

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Statistics

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Jennifer H. Madans, Ph.D., Associate 

Director for Science

Office of Analysis and Epidemiology

Linda T. Bilheimer, 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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