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A Report from the Autism and Developmental Disabilities
Monitoring (ADDM) Network
What is the Autism and Developmental Disabilities
Monitoring (ADDM) Network?
The ADDM Network is a group of programs funded by the
Centers for Disease Control and Prevention (CDC) to
determine the prevalence of the Autism Spectrum
Disorders (ASDs) in United States communities. Its goals
are:
o provide baseline data about ASD prevalence (how
common ASDs are in a specific place and time).
- To describe the population of children with
ASDs.
- To compare ASD prevalence in different groups of
children and different areas of the country.
- To identify changes in ASD prevalence over time.
- To understand the impact of autism and related
conditions in U.S. communities.
The ADDM Network’s first two ASD prevalence reports
were released in the February 9, 2007, issue of the
Morbidity
and Mortality Weekly Report Surveillance Summaries.
Six ADDM sites evaluated the prevalence of ASDs for
children who were eight years old in 2000 (born in
1992). An additional eight sites determined ASD
prevalence for children who were eight in 2002 (born in
1994). The ADDM Network determines ASD prevalence
through the review of health and education records in
collaboration with state health departments, diagnostic
facilities, and school systems in the specified areas.
By studying the prevalence of ASDs over several time
points, we can find out if the number of children with
ASDs is rising, dropping, or staying the same in these
areas. We can also compare the number of children with
ASDs in different areas or groups of people studied in
the ADDM Network data. This information can help us look
for causes of ASDs.
Autism and Developmental
Disabilities Monitoring (ADDM) Network
What do the ADDM Network findings tell us?
The average ASD prevalence was 6.7 per 1,000 for
8-year-olds in 2000 and 6.6 per 1,000 8-year-olds in
2002 in several areas of the United States. That’s about
1 in 150 children in these communities. Most ADDM
Network sites found 5.2 to 7.6 per 1,000 eight-year-old
children with ASDs in 2002. The prevalence was much
lower (3.3 per 1,000) in Alabama and higher (10.6 per
1,000) in New Jersey in 2002. Prevalence stayed the same
from 2000 to 2002 in four of the six sites with data for
both years. It rose slightly in Georgia and
significantly in West Virginia, indicating the need for
tracking prevalence over time.
More information about the 2000 surveillance year
- Approximately 4.5 percent of U.S.
eight-year-old children (i.e., children born in
1992) from six states - Arizona, Georgia,
Maryland, New Jersey, South Carolina and West
Virginia. A total of 1,252 eight-year olds were
identified as having an ASD.
- Six sites collected data: Arizona (one
county including metro Phoenix), Georgia (five
counties in metro Atlanta), Maryland (four
counties plus Baltimore City), New Jersey (four
counties including the city of Newark), South
Carolina (23 counties in the Coastal and PeeDee
regions), and West Virginia (entire state).
- Prevalence of ASDs among eight-year-old
children ranged from 4.5 per 1,000 (West
Virginia) to 9.9 per 1,000 (New Jersey) with the
other four sites from 5.5 to 6.5 children with
ASD per 1,000 eight-year-old children. (Average
across all six sites was 6.7 per 1,000
children.)
- ASD prevalence was higher among boys than
among girls, ranging from three to more than
five boys for every girl with ASD.
- Boys: 6.6 per 1,000 (West Virginia) to 14.6 per 1,000 (New
Jersey)
Girls: 2.0 per 1,000 (Georgia) to 4.2 per 1,000 (New Jersey)
- ASD prevalence among white non-Hispanic
children ranged from 4.5 per 1,000 (West
Virginia) to 11.0 per 1,000 (New Jersey). For
black non-Hispanic children, ASD prevalence
ranged from 5.3 per 1,000 (Georgia) to 10.6 per
1,000 (New Jersey).
- The median age of earliest ASD diagnosis
ranged from four years, four months (New Jersey
and West Virginia) to four years, eight months
(Georgia). But, for 69 –88 percent of children
with an ASD, concerns about the child’s
development had been recorded before three years
of age.
More information about the 2002 surveillance year
- Approximately 10 percent of U.S.
eight-year-old children (i.e., children born in
1994), from 14 states - Alabama, Arizona,
Arkansas, Colorado, Georgia, Maryland, Missouri,
New Jersey, North Carolina, Pennsylvania, South
Carolina, Utah, West Virginia and Wisconsin. A
total of 2,685 eight-year-olds were identified
as having an ASD.
- Fourteen sites collected data: Alabama (32
counties), Arizona (one county including metro
Phoenix), Arkansas (entire state), Colorado (two
counties in metro Denver), Georgia (five
counties in metro Atlanta), Maryland (four
counties plus Baltimore City), Missouri (five
counties in metro St. Louis), New Jersey (four
counties including the city of Newark), North
Carolina (eight central counties), Pennsylvania
(Philadelphia County), South Carolina (23
counties in the Coastal and PeeDee regions),
Utah (three counties around metro Salt Lake
City), West Virginia (entire state), Wisconsin
(10 counties in the southeast including
Milwaukee)
- ASD prevalence among eight-year-old children
was 3.3 per 1,000 (Alabama) to 10.6 per 1,000
(New Jersey). But, 12 of the 14 sites had a
closer range of 5.2 to 7.6 per 1,000 children
(average across all 14 sties was 6.6 per 1,000
eight-year-old children).
- In 2002, four sites (Alabama, Missouri,
Pennsylvania and Wisconsin) relied on
information from health sources. On average, the
prevalence was lower in those sites than in the
other 10 sites that combined information from
health and education sources. In both study
years, many ASD cases were found through
education sources alone.
- ASD prevalence was higher among boys than
among girls, ranging from more than three to
more than six boys for every girl with ASD.
- Boys: 5.0 per 1,000 (Alabama) to 16.8 per 1,000 (New Jersey)
- Girls: 1.4 per 1,000 (Alabama) to 4.0 per 1,000 (New Jersey)
- ASD prevalence among white non-Hispanic
children ranged from 3.3 per 1,000 (Alabama) to
12.5 per 1,000 (New Jersey). For black
non-Hispanic children, ASD prevalence ranged
from 3.4 per 1,000 (Alabama) to 7.7 per 1,000
(New Jersey). Among Hispanic children, it ranged
from 0.3 per 1,000 (Wisconsin) to 9.7 per 1,000
(New Jersey).
- The median age of earliest ASD diagnosis
ranged from four years, one month (Utah) to five
years, six months (Alabama). But for 51–91
percent of children with an ASD, developmental
concerns had been recorded before three years of
age.
To learn more about CDC’s work on autism, please visit
www.cdc.gov/autism.
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Date:
February 08, 2007
Content source: National Center on Birth Defects and Developmental
Disabilities
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