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Wendy Klag Center for Autism & Developmental Disabilities

Autism and Developmental Disabilities Monitoring Network (ADDM)

Autism and Developmental Disabilities Network (ADDM)The Autism and Developmental Disabilities Network (ADDM) is a CDC-funded project that aims to monitor the number of cases of autism and other developmental disabilities in different regions of this country to provide accurate, population-based estimates of the prevalence of these disabilities in young children. 

Li-Ching Lee, PhD, has been the principal investigator of the Maryland site, based at the Bloomberg School of Public Health, since the project first began.

The latest ADDM prevalence report related to Autism Spectrum Disorders (ASD) was released in April 2018. The national 2018 report, which focused on data from 2014, found an overall prevalence of 1 in 59 children with ASD. As in prior years, the prevalence among boys was four times higher than among girls. In the new report, the prevalence was 1 in 38 boys, compared to 1 in 152 girls.

Research sites in 11 states participated, including Maryland.  Other sites were in Arizona, Arkansas, Colorado, Georgia, Minnesota, Missouri, New Jersey, North Carolina, Tennessee and Wisconsin.

The Maryland data were derived from health and special education records of children who were 8 years old and living in Baltimore County in 2014. Taking a look at Maryland's numbers, the overall prevalence was found to be 1 in 50 children, with 1 in 31 boys and 1 in 139 girls meeting criteria for ASD.

Monitoring Strategy

The surveillance system is a multiple source, records-based population surveillance system, currently focused on ASDs with plans to expand to other developmental disabilities in the future.  The Maryland ADDM site collaborates with the Maryland State Department of Education and local hospitals to obtain data about potential ASD cases.

What if I have a concern about a child's development?

The CDC recommends that parents track their child's development and act quickly to get their child screened if they have a concern. Free checklists and information for parents, physicians and child care providers are available at this CDC web page.

June 4 symposium to take deeper look at autism prevalence

The Wendy Klag Center for Autism and Developmental Disabilities will host a free symposium, "Why Counts Count: Today's Autism Numbers, Tomorrow's Projections," from 1:30 to 4 p.m. Monday June 4 in Sheldon Hall.  The symposium will feature three main talks, followed by a panel discussion. A reception will follow in the Gallery from 4 to 5 p.m.  The main talk topics are: 

  • Presentation of new and historic autism prevalence data, by Li-Ching Lee, PhD, principal investigator of the Maryland site of the Autism and Developmental Disabilities Monitoring Network
  • Perspective of autism services agency: Mission and overview of services for teens and adults, by Eric Salzano, executive director of CSAAC, a Montgomery County, MD autism service provider
  • Demographic projections of autism spectrum disorder among adults in Maryland and the United States, by Qingfeng Li, PhD, and Li-Ching Lee, of the Johns Hopkins Bloomberg School of Public Health

Wendy Klag Center founder Mike Klag will make introductory remarks, and WKC Director Dani Fallin will moderate. Panelists will include Zosia ZaksM.Ed., C.R.C, the manager of programs and education at Towson University's Hussman Center for Adults with Autism; Maureen Van Stone, Esq., interim director of the Maryland Center for Developmental Disabilities; Terri Savage, Ed.D., acting executive director of the Howard County Department of Special Education; and Eric Salzano, executive director of CSAAC

The event will be webcast live at  If you would like to attend in person and are not affiliated with Johns Hopkins, please RSVP at this Eventbrite link. Questions? Contact Michelle Landrum.