Key Findings: Trends in the Prevalence of Developmental Disabilities in U. S. Children, 1997–2008

Researchers from the Centers for Disease Control and Prevention (CDC), in collaboration with researchers from the Health Resources and Services Administration (HRSA), have published a new study in Pediatrics: “Trends in the Prevalence of Developmental Disabilities in U.S. Children, 1997–2008.” This study determined the prevalence of developmental disabilities in U.S. children and in selected populations for a 12-year period. You can read the abstract here. The findings from this article are summarized in the following text.

Main findings from this study:

Data from the study showed that developmental disabilities (DDs) are common: about 1 in 6 children in the U.S. had a DD in 2006–2008. These data also showed that prevalence of parent-reported DDs has increased 17.1% from 1997 to 2008. This study underscores the increasing need for health, education and social services, and more specialized health services for people with DDs.

• The prevalence of any DD in 1997–2008 was 13.87%
  • Prevalence of learning disabilities was 7.66%;
  • Prevalence of attention deficit hyperactivity disorder (ADHD) was 6.69%;
  • Prevalence of other developmental delay was 3.65%; and,
  • Prevalence of autism was 0.47%.
• Over the last 12 years, the
  • Prevalence of DDs has increased 17.1%—that’s about 1.8 million more children with DDs in 2006–2008 compared to a decade earlier;
  • Prevalence of autism increased 289.5%;
  • Prevalence of ADHD increased 33.0%; and,
  • Prevalence of hearing loss decreased 30.9%.
• In addition, data from this study showed
  • Males had twice the prevalence of any DD than females and more specifically had higher prevalence of ADHD, autism, learning disabilities, stuttering/stammering and other DDs;
  • Hispanic children had lower prevalence of several disorders compared to non-Hispanic white and non-Hispanic black children, including ADHD and learning disabilities;
  • Non-Hispanic black children had higher prevalence of stuttering/stammering than non-Hispanic white children;
  • Children insured by Medicaid had a nearly two-fold higher prevalence of any DD compared to those with private insurance; and,
  • Children from families with income below the federal poverty level had a higher prevalence of DDs.

To better understand why the prevalence has increased, future research should focus on understanding the influence of increases in the prevalence of known risk factors, changes in acceptance and awareness of conditions, and benefits of early intervention services.

About developmental disabilities and this study:

Developmental disabilities are a diverse group of severe chronic conditions that are due to mental and/or physical impairments. People with developmental disabilities have problems with major life activities such as language, mobility, learning, self-help, and independent living. Developmental disabilities begin anytime during development up to 22 years of age and usually last throughout a person’s lifetime.

For this study, researchers aimed to determine the prevalence of DD in U.S. children overall and in certain populations from 1997–2008. Researchers analyzed responses from the 1997–2008 National Health Interview Surveys. A total of 119,367 children ages 3–17 were included in the study. Parents or legal guardians were asked if their child had any of the following conditions: ADHD, autism, blindness, cerebral palsy, moderate to profound hearing loss, intellectual disability, learning disorders, seizures, stuttering/stammering, and other developmental delay.

Developmental Disabilities: CDC activities

CDC is part of a larger group of public and private organizations working to better understand developmental disabilities through surveillance, research, and early identification. CDC is undertaking efforts to:

• study how common developmental disabilities are and who is more likely to have them;
• find the causes of developmental disabilities and the factors that increase the chance that a person will have one; and,
• learn how people with developmental disabilities can improve the quality of their lives.

Surveillance (Tracking): The Autism and Developmental Disabilities Monitoring (ADDM) Network is a group of programs funded by CDC to determine the number of people with autism spectrum disorders (ASDs) in the U.S. The ADDM sites all collect data using the same surveillance methods, which are modeled after CDC’s Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP). MADDSP monitors the occurrence of selected developmental disabilities, including intellectual disability, cerebral palsy, hearing loss, vision impairment, and ASDs.

Research: The Study to Explore Early Development (SEED) is a multi-year study funded by CDC. It is currently the largest study in the United States to help identify factors that may put children at risk for ASDs and other developmental disabilities. Understanding the risk factors that make a person more likely to develop an ASD or other developmental disability will help us learn more about the causes.

Improving Early Identification of Developmental Delay and Disability: CDC’s “Learn the Signs. Act Early.” program aims to improve early identification of children with autism and other developmental disabilities so children and families can get the services and support they need as early as possible.

For free downloadable fact sheets about developmental disabilities, please visit https://www.cdc.gov/NCBDDD/actearly/facts.html.

CDC also has Web pages on these specific topics:

Attention Deficit Hyperactivity Disorder (ADHD)
Autism Spectrum Disorders
Cerebral Palsy

Reference

Boyle CA, Boulet S, Schieve L, Cohen RA, Blumberg SJ, Yeargin-Allsopp M, Visser S, Kogan MD. Trends in the Prevalence of Developmental Disabilities in US Children, 1997–2008. Pediatrics. 2011 [epub ahead of print].