Number 393 + October 26, 2007

Electronic Medical Record Use by Office-Based

Physicians and Their Practices: United States, 2006

by Esther S. Hing, M.P.H.; Catharine W. Burt, Ed.D.; and David A. Woodwell, Division of Health Care Statistics

Abstract

Objectives—This report presents the latest information on the use of electronic

medical records in physician offices. Percentages of medical practices and

physicians within the practices using electronic medical records (EMR) are

presented for 2006 by selected physician and practice characteristics.

Methods—Data from the physician induction interviews of the 2006 National

Ambulatory Medical Care Survey (NAMCS) are presented. NAMCS includes a

national probability sample of nonfederal office-based physicians who saw patients

in an office setting. Sample data were weighted to produce national estimates of

physicians. Estimates of medical practices were derived from NAMCS physician

data by adjusting the weighting scheme using a multiplicity estimator.

Results—In 2006, 29.2 percent of office-based physicians reported using full or

partial EMR systems, which represented a 22% increase since 2005 and a 60%

increase since 2001, when the NAMCS began monitoring this technology. Starting

in 2005, the NAMCS included questions about EMR system features that health

information technology experts consider minimal for a comprehensive EMR, namely

computerized orders for prescriptions, computerized orders for tests, reporting of

test results (lab or imaging), and clinical notes. Based on these requirements,

12.4 percent of physicians surveyed used comprehensive EMR systems in 2006, a

figure not significantly different from the 9.3 percent reported for 2005. From 2005

to 2006, the percentage of medical practices using full or partial EMR systems

increased by 42% (from 18.3 to 25.9 percent), but the percentage of medical

practices using a comprehensive EMR system did not change.

Keywords: physicians c electronic medical records c NAMCS

Introduction

This report examines use of

electronic medical record (EMR)

systems by office-based physicians in

2006, as well as their plans to install

new EMR systems or replace their

current systems within the next 3 years.

Changes in EMR use by physicians

since 2001 are also examined (1,2). Two

measures of EMR use are examined: use

of full or partial (part paper) electronic

medical records, and use of EMR

systems that include features health

information technology experts consider

minimal for a comprehensive EMR,

namely computerized orders for

prescriptions, computerized orders for

tests, reporting of test results (lab or

imaging), and clinical notes (3). Because

the decision to use an EMR system is

usually made at the organizational level

of the practice, rather than by an

individual physician, the report also

presents estimates of medical practices

that use EMR systems. Estimates of

medical practices can be derived from

the National Ambulatory Medical Care

Survey (NAMCS) physician data by

adjusting the weighting scheme using a

multiplicity estimator. The number of

physicians in the practice is used to

modify the physician weight to yield a

practice weight (4). This report presents

2006 estimates of EMR use by both

office-based physicians and their

practices by selected practice and

location characteristics.

Methods

NAMCS is an annual probability

survey of nonfederal, office-based

physicians providing direct patient care

who practice in the 50 states or the

District of Columbia, excluding

radiologists, anesthesiologists, and

pathologists. The survey is conducted by

the Centers for Disease Control and

Prevention’s National Center for Health

Statistics. A sample of 3,350 officebased physicians who reported that they

were in direct patient care was taken

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES 

Centers for Disease Control and Prevention 

National Center for Health Statistics 
2 Advance Data No. 393 + October 26, 2007

from the masterfiles of the American

Medical Association and the American

Osteopathic Association. The sample

design includes 112 geographic primary

sampling units (PSUs). Within those

PSUs, physicians were stratified by

specialty, and a sample of physicians

was selected. Physicians were randomly

assigned to 1 of 52 reporting weeks

throughout the year. Of the 3,350

sampled physicians, 2,117 responded

that they were eligible to participate in

the survey (inscope). Eligible physicians

must see patients in an office setting. In

2006, responses were obtained from

1,311 eligible sampled physicians who

saw patients during their sample week

and those who did not, for an

unweighted response rate of 61.9 percent

(63.6 percent weighted). For more

information about NAMCS see

www.cdc.gov/nchs/NAMCS.htm.

During the face-to-face induction

interview for NAMCS, sampled

physicians were asked to respond to

questions about the scope and size of

their office-based practices, including

whether or not they used full or partial

(part paper) EMRs. If they responded

‘‘yes’’ to either full or partial electronic

records, they were asked seven

additional questions about the features

of their EMR system. Estimates of EMR

use were calculated in two ways:

physicians were considered to use

EMRs if they reported ‘‘yes’’ to the

general question on EMR use, and

physicians were considered to use

comprehensive EMR systems if they

gave a ‘‘yes’’ response to all four

features deemed minimally necessary for

a comprehensive EMR system. The four

features required of an EMR system are

computerized orders for prescriptions,

computerized orders for tests, test

results, and clinical notes. The

functionality of comprehensive EMR

systems approximates the type of

electronic health record systems

proposed by the President to be used by

most physicians by 2014 (3).

It should be noted that some items

on EMR features collected in the 2005

survey were refined in the 2006 survey.

For the first time, information on

whether an EMR feature was available

but turned off was collected (2.3 percent

of physicians). In this report, any feature

0 

10 

20 

30 

2001 2002 2003 2004 2005 2006

NOTES: EMR is electronic medical record. Trend for “Any EMR” is significant. “Any EMR” is medical records that are 

either fully or partially electronic. Comprehensive EMR system includes four minimum features: computerized orders 

for prescriptions, computerized orders for tests, test results (lab or imaging), and clinical notes. Includes nonfederal, 

office-based physicians who see patients in an office setting. Excludes radiologists, anesthesiologists, and 

pathologists. 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey, 2001-2006. 

Percent of physicians

18.2 

17.3 17.3 

20.8 

23.9 

9.3 

12.4 

29.2 

Comprehensive EMR system 

Any EMR 

Figure 1. Percentage of office-based physicians using electronic medical records and

using comprehensive electronic medical record systems: United States, 2001–2006

reported as turned off was considered

available within the EMR. Information

on availability of imaging results within

the EMR was also collected for the first

time in 2006. In this report, the presence

of either lab or imaging results reported

in 2006 is considered equivalent to

having test results (collected in 2005)

available within the EMR. Finally, the

clinical notes feature collected in 2006

is considered equivalent to the physician

notes feature collected in 2005.

Data on general use of EMRs were

missing for fewer than 2 percent of

physicians; for this analysis, cases

missing data were considered as not

having EMRs. If missing cases were

randomly distributed, this approach

would underestimate the incidence of

EMR adoption.

The report presents national

estimates of EMR use among both

medical practices and physicians within

the practices. To address that the

NAMCS is based on a multistage

sample of physicians, compound

sampling weights were applied to make

national estimates of EMR use and

corresponding estimates of sampling

error (5). Estimates of the medical

practices can be derived from the

NAMCS physician data by adjusting the

weighting scheme using a multiplicity

estimator. The number of physicians in

the practice is used to modify the

physician weight to yield a practice

weight (4). Statements of differences in

estimates are based on statistical tests

(e.g., chi-square tests of independence,

Student’s t, or weighted linear

regression) with significance at the p<

0.05 level. Additional information about

the county in which the physician’s

practice was located was obtained from

the Area Resource File (ARF) (6).

Results

+ In 2006, approximately 29.2 percent

of physicians (95% confidence

interval: 25.9–32.5) reported using

full (14.5 percent) or partial

(14.7 percent) EMR systems in their

office-based practices. This represents

a 22% increase since 2005 and a 60%

increase since 2001 (Figure 1). EMR

use did not vary by physician gender

or specialty type; however, EMR use

declined with physician age (Table 1).

+ EMR use was related to several

practice characteristics. EMR use

increased with the size of the

practice, as measured by number of

physicians (Figure 2). EMR use was

higher among health maintenance

organizations compared with
Advance Data No. 393 + October 26, 2007 3

0 

10 

20 

30 

40 

50 

Any EMR Comprehensive EMR system

Solo Partner 3-5 6-10 11 or more

NOTES: EMR is electronic medical record. Both trends are significant. “Any EMR” is medical records that are 

either fully or partially electronic. Comprehensive EMR system includes four minimum features: 

computerized orders for prescriptions, computerized orders for tests, test results (lab or imaging), and 

clinical notes. Includes nonfederal, office-based physicians who see patients in an office setting. Excludes 

radiologists, anesthesiologists, and pathologists. 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey, 2006. 

Percent of physicians 

Number of physicians in practice 

24.0 

7.1 

28.0 

13.4 

30.0 

9.7 

16.6 

46.5 

26.6 

30.9 

Figure 2. Percentage of physicians using electronic medical records and using

comprehensive electronic medical record systems by practice size: United States, 2006

0 20 40 60 80 100 

Yes Maybe No Unknown or blank

Fully electronic 

Part paper, 

part electronic 

No or unknown 

NOTES: Includes nonfederal, office-based physicians who see patients in an office setting. Excludes 

radiologists, anesthesiologists, and pathologists. 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey, 2006. 

Percent of physicians 

Percent distribution 

10.0 74.8 11.4 

25.3 17.7 44.1 12.8 

30.7 12.1 38.8 18.4

3.9 

Figure 3. Percent distribution of physicians planning new or replacement electronic

medical record systems within next 3 years by whether current system is fully or partially

electronic: United States, 2006

nonmetropolitan statistical areas

(20.2 percent).

+ In 2006, 12.4 percent of physicians

(95% CI: 9.9–14.9) reported having

the four features deemed minimally

necessary for a comprehensive EMR

system (last column in Tables 1 and

2). Although it appears that this

percentage increased since 2005

(Figure 1), the difference is not

statistically significant. The

relationships observed between this

measure of EMR use and

characteristics of the physician,

practice, and location characteristics

were generally the same as those

found for use of full or partial EMRs,

with the following exceptions: use of

comprehensive EMR systems was

higher among physicians in multispecialty practices than in solo or

single-specialty practices, however,

use of comprehensive EMR systems

was unrelated to the number of

managed care contracts, or

metropolitan statistical area status.

+ Table 3 presents responses to the

seven items concerning the specific

features of the EMR system used by

the physician. Percentages are

provided for all physicians, as well as

for physicians reporting that their

medical record systems are fully or

partially electronic. Although

26.2 percent of physicians have

electronic patient demographics, only

6.6 percent reported having electronic

public health reporting capabilities. In

2006, 20.4 percent of physicians

could view either lab (19.3 percent)

or imaging (15.0 percent) results

electronically. Among physicians with

fully electronic systems, 63.7 percent

reported their EMR systems included

reminders for guideline-based

interventions and/or screening tests,

and about one-half (52.9 percent) sent

prescriptions to the pharmacy

electronically, or had tests orders sent

physicians in private practice and

other types of ownership, and varied

by number of managed care contracts

(Table 1).

+ Physicians in the West (42.3 percent)

were more likely to use EMRs than

were those in the Northeast

(23.5 percent), Midwest

(29.3 percent), and South

(24.2 percent) (Table 2). Physicians in

metropolitan statistical areas

(30.3 percent) were more likely to use

EMRs than were those in

electronically (46.5 percent) (Table 3).

+ In 2006, 23.9 percent of office-based

physicians reported that they planned

to install new EMR systems or

replace their current systems within

the next 3 years, and 14.9 percent

reported that they might do so (data

not shown). Physicians currently

without EMR systems were more
4 Advance Data No. 393 + October 26, 2007

0 

10 

20 

30 

2003–2004 2005 2006 1 

1

Detailed features of electronic medical record systems were not included in the 2003–2004 surveys. 

NOTES: EMR is electronic medical record. Trend for “any EMR” is significant. “Any EMR” is medical records that 

are either fully or partially electronic. Comprehensive EMR system includes four minimum features: computerized 

orders for prescriptions, computerized orders for tests, test results (lab or imaging), and clinical notes. Medical 

practices were estimated using a multiplicity estimator (See reference 4 for details). Medical practice estimates 

were based on nonfederal, office-based physicians who see patients in an office setting. Excludes radiologists, 

anesthesiologists, and pathologists. 

SOURCE: CDC/NCHS, National Ambulatory Medical Care Survey, 2003-2006. 

Percent of medical practices 

Comprehensive 

EMR system 

Any EMR 25.9 

9.0 

6.0 

18.3 

15.0 

Figure 4. Percentage of medical practices using electronic medical records and using

comprehensive electronic medical record systems: United States, 2003–04 through 2006

likely to report plans to install new

EMR systems within the next 3 years

compared with those with fullyelectronic systems. Physicians with

partially electronic systems were

more likely to report plans to replace

current systems within the next 3

years compared with those with fully

electronic systems (Figure 3).

+ Decisions to adopt a new EMR

system are usually made at the

practice level. The percentage of

medical practices that reported using

any form of electronic medical

records increased by 42% since 2005

and by 73% since 2003–2004

(Figure 4). Although the percentage

of medical practices using a

comprehensive EMR system appeared

to increase between 2005 and 2006,

the difference was not significant

(Figure 4).

Conclusion

These estimates show recent

progress toward the goal of universal

electronic health records. Between 2005

and 2006, the percentage of office-based

medical practices using any form of

EMR increased by 42% (Figure 4),

while the percentage of physicians

within these practices using any form of

EMR increased by 22% (Figure 1). In

2006, nearly one in four physicians

without an EMR system planned to

install a new EMR system within the

next 3 years, while 31 percent of

physicians with partially-electronic

systems planned to replace their current

systems within the next 3 years. There

continues to be room for improvement.

In 2006, about 1 in 10 (9.0 percent)

office-based medical practices and

physicians within these practices

(12.4 percent) had an EMR system with

the minimal four features of a

comprehensive system, unchanged since

2005 (Figures 1 and 4). In 2006,

features of EMR systems in use varied

widely; availability of EMR functions to

order prescriptions or tests electronically

and public health reporting capabilities

lag behind other features of the system.

This study confirms previous research

(7,8) that showed that not all EMR

features available to physicians are used.

The NAMCS data found that about

2.3 percent of physicians turn off some

available features. Finally, this study

found that even among physicians who

report using fully electronic medical

record systems, only 63.7 percent

reported using reminders for guidelinebased interventions or screening tests

and about one-half used computerized

prescription order entry (52.9 percent) or

computerized test order entry

(46.5 percent) features within their EMR

system (Table 3). These are the features

that may be most likely to result in

improved management and quality of

care. The 2006 NAMCS findings

suggest continued efforts are needed to

increase the adoption rate of

comprehensive EMR systems.

References

1. Burt CW, Hing E, Woodwell DA.

Electronic medical record use by

office-based physicians: United

States, 2005. Health E Stat. 2006.

Available from: http://www.cdc.gov/

nchs/products/pubs/pubd/hestats/­

electronic/electronic.htm (accessed 10

August 2007).

2. Cherry DK, Burt CW, Woodwell,

DA. National Ambulatory Medical

Care Survey: 2001 summary.

Advance data from vital and health

statistics; no 337. Hyattsville, MD:

National Center for Health Statistics.

2003.

3. Blumenthal D, DesRoches C,

Donelan K, et al. Health information

technology in the United States: The

information base for progress. Robert

Wood Foundation. 2006.

4. Hing E, Burt CW. Office-based

medical practices: Methods and

estimates from the National

Ambulatory Medical Care Survey.

Advance data from vital and health

statistics; no 383. Hyattsville, MD:

National Center for Health Statistics.

2007.

5. Research Triangle Institute.

SUDAAN User’s Manual, Release

9.0. Research Triangle Park, NC:

Research Triangle Institute. 2004.

6. HRSA. User documentation for the

area resource file (ARF): February

2005 release. Health Services and

Resources Administration.

7. Simon SR, Kaushal R, Cleary P, et

al. Physicians and Electronic Health

Records. Arch Intern Med. 167:507–

12. 2007.

8. Grossman JM, Gerland A, Reed MC,

Falhlman C. Physicians’ experience

using commericial E-prescribing

systems. Health Affairs-Web

Exclusive w393–w404. 2007.
Advance Data No. 393 + October 26, 2007 5

Table 1. Use of electronic medical records by characteristics of office-based physicians: United States, 2006

Percent of physicians

Percent of physicians reporting minimum

Percent distribution reporting use of fully features for

of all physicians or partially comprehensive

(based on weighted electronic medical electronic medical

responses from 1,311 records1 record systems2

Physician and practice characteristics sample physicians) (standard error) (standard error)

All physicians3 ............................. 100.0 29.2 (1.7) 12.4 (1.3)

Physician age4,5

Under 35 years ............................. 6.4 47.0 (6.6) *24.7 (6.2)

35–44 years ............................... 28.3 35.4 (3.2) 15.6 (2.5)

45–64 years ............................... 34.2 30.1 (2.8) 12.4 (2.0)

55–64 years ............................... 24.2 22.4 (2.9) 8.4 (1.6)

65 years and over ........................... 7.0 *7.6 (2.6) *1.6 (1.0)

Physician specialty type6

Primary care............................... 49.4 28.2 (2.4) 14.3 (2.0)

Surgical ................................. 21.2 31.3 (3.0) 12.3 (2.3)

Medical.................................. 29.4 29.5 (2.7) 9.3 (1.6)

Physician gender

Male ................................... 75.4 29.3 (2.0) 11.7 (1.3)

Female .................................. 24.6 29.0 (3.3) 14.5 (2.7)

Practice size4,5

Solo .................................... 34.1 24.0 (2.8) 7.1 (1.7)

Partner .................................. 12.3 28.0 (4.3) 9.7 (2.6)

3–5 .................................... 29.9 30.0 (3.0) 13.4 (2.1)

6–10 ................................... 15.3 30.9 (4.2) 16.6 (3.6)

11 or more ................................ 8.4 46.5 (6.4) 26.6 (5.3)

Breadth of specialization5

Solo and single-specialty ...................... 79.0 28.0 (2.0) 10.4 (1.4)

Multi-specialty.............................. 20.5 34.5 (3.5) 20.5 (3.3)

Unknown................................. 0.4 – . . .

Practice ownership4,5

Physician or physician group .................... 81.8 26.9 (1.7) 9.9 (1.1)

Health maintenance organization (HMO) ............. 2.7 75.8 (8.5) 60.4 (10.3)

Other ................................... 15.5 33.5 (4.7) 17.2 (3.9)

Number of managed care contracts4

None ................................... 12.4 26.5 (4.3) *10.7 (3.8)

1–2 .................................... 8.3 39.7 (5.9) 15.1 (4.2)

3–10 ................................... 33.7 23.2 (2.9) 9.8 (2.0)

More than 10 .............................. 39.5 32.2 (2.8) 13.4 (2.0)

Unknown................................. 6.1 34.8 (6.6) *20.0 (6.2)

Percentage revenue from Medicaid

Under 5% ................................ 31.7 29.4 (2.7) 9.9 (1.7)

5–19% .................................. 29.9 30.3 (2.9) 12.9 (2.0)

20% or more .............................. 26.2 28.0 (3.2) 13.6 (2.6)

Unknown................................. 12.2 28.8 (5.0) 14.9 (4.0)

* Figure does not meet standards of reliability or precision.

– Quantity zero.

...Category not applicable. 1

Electronic medical record (EMR) refers to physicians’ reporting that their medical records are either fully or partially electronic. Percentages may be underestimates because physicians missing

information on EMR use (1.9 percent) are assumed to not use EMRs. 2

Minimum features include computerized prescription ordering, computerized test ordering, test results (lab or imaging), and clinical notes; minimum features that were available but turned off were

included.

3

Includes nonfederal, office-based physicians who see patients in an office setting. Excludes radiologists, anesthesiologists, and pathologists. 4

Significant relationship between use of full or partial EMR and physician or practice characteristic based on chi-square test. 5

Significant relationship between use of comprehensive EMR system and physician or practice characteristic based on chi-square test. 6

Specialty type based on categorization of physician subspecialties obtained from the American Medical Association (see reference 4 appendix).
6 Advance Data No. 393 + October 26, 2007

Table 2. Use of electronic medical records by location characteristics of office-based physicians: United States, 2006

Percent Percent of Percent of physicians

distribution of physicians reporting minimum

all physicians reporting use of features for

(based on fully or partially comprehensive

weighted responses electronic medical electronic medical

from 1,311 records1 record system2

Location characteristic sample physicians) (standard error) (standard error)

All physicians3 .................................. 100.0 29.2 (1.7) 12.4 (1.3)

Geographic region4,5

Northeast ..................................... 20.6 23.5 (2.7) 7.6 (1.6)

Midwest ...................................... 20.0 29.3 (3.2) 14.1 (2.7)

South........................................ 36.5 24.2 (3.0) 8.7 (1.9)

West ........................................ 22.9 42.3 (4.3) 21.1 (3.5)

Metropolitan status4

Metropolitan statistical area .......................... 89.0 30.3 (1.9) 13.0 (1.3)

Nonmetropolitan statistical area........................ 11.0 20.2 (3.0) *7.7 (2.5)

Percent of county population that is non-Hispanic white6

Over 75% ..................................... 43.0 26.8 (2.6) 13.4 (2.1)

50–75% ...................................... 32.4 30.2 (3.3) 9.4 (2.3)

Under 50% .................................... 24.6 32.1 (4.2) 14.6 (2.8)

* Figure does not meet standards of reliability or precision. 1

Electronic medical record (EMR) refers to physicians’ reporting that their medical records are either fully or partially electronic. Percentages may be underestimates because physicians missing

information on EMR use (1.9 percent) are assumed to not use EMRs. 2

Minimum features include computerized prescription ordering, computerized test ordering, test results (lab or imaging), and clinical notes; minimum features that were available but turned off were

included.

3

Includes nonfederal, office-based physicians who see patients in an office setting. Excludes radiologists, anesthesiologists, and pathologists. 4

Significant relationship between use of full or partial EMR and location characteristic based on chi-square test. 5

Significant relationship between use of comprehensive EMR system and location characteristic based on chi-square test. 6

Based on data from the Area Resource File (reference 6).
Advance Data No. 393 + October 26, 2007 7

Table 3. Percentage of office-based physicians reporting selected features of their system, according to whether medical records are

reported to be fully or partially electronic: United States, 2006

All Standard Fully Standard Partially Standard

Electronic medical record system feature physicians1 error electronic2 error electronic3 error

Patient demographics ................................ 26.2 1.6 94.7 2.1 82.1 3.8

Physician clinical notes ............................... 22.9 1.5 93.9 1.7 62.2 4.5

Medical history and follow-up notes ...................... 19.2 1.4 83.3 2.9 47.8 5.0

Guideline-based interventions and/or screening test reminders ..... 13.1 1.2 63.7 4.0 26.3 3.7

Test results (lab or imaging) ............................ 20.4 1.5 83.6 3.0 53.1 4.5

Lab results ..................................... 19.3 1.5 81.5 3.1 48.2 4.4

Out of range values highlighted ....................... 13.3 1.2 61.4 3.8 29.1 4.1

Imaging results ................................... 15.0 1.3 67.1 4.3 34.1 4.1

Electronic images returned .......................... 7.4 0.8 34.9 4.1 15.8 3.0

Computerized orders for prescriptions ...................... 19.5 1.4 84.0 2.6 49.4 4.5

Drug interaction or contraindication warnings provided .......... 14.6 1.3 66.2 3.8 34.0 4.1

Prescriptions sent to pharmacy electronically ................ 11.9 1.3 52.9 4.7 28.9 4.2

Computerized orders for tests ........................... 16.2 1.4 72.7 3.8 37.8 4.5

Test orders sent electronically.......................... 9.5 1.1 46.5 4.1 18.0 3.7

Public health reporting................................ 6.6 0.8 25.5 3.5 18.3 3.0

Notifiable diseases sent electronically ..................... 3.5 0.6 15.2 2.7 *7.5 2.4

* Figure does not meet standards of reliability or precision. 1

Based on responses from 1,311 physicians. Includes nonfederal, office-based physicians who see patients in an office setting. Excludes radiologists, anesthesiologists, and pathologists. 2

Based on 199 sample physicians reporting use of fully electronic medical records (14.5 percent of physicians, weighted). 3

Based on 176 sample physicians reporting use of partially electronic medical records (14.8 percent of physicians, weighted).

NOTES: Percentages may be underestimates because physicians missing information on electronic medical record (EMR) use (1.9 percent) are assumed to not use EMRs. Features are reported

as available even if they are turned off.
8 Advance Data No. 393 + October 26, 2007

Suggested citation

Hing ES, Burt CW, Woodwell DA. Electronic

medical record use by office-based physicians

and their practices: United States, 2006.

Advance data from vital and health statistics;

no 393. Hyattsville, Maryland: National Center

for Health Statistics. 2007.

Copyright information

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public domain and may be reproduced or

copied without permission; citation as to

source, however, is appreciated.

National Center for Health Statistics

Director

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Acting Co-Deputy Directors

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Michael H. Sadagursky

U.S. DEPARTMENT OF

HEALTH & HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics

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DHHS Publication No. (PHS) 2008-1250