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Autism Spectrum Disorders: Test Your Knowledge

Autism spectrum disorders are a group of developmental disabilities that can cause significant social, communication and behavioral challenges.

Diagnosing autism spectrum disorders can be difficult since there is no medical test, like a blood test, for diagnosis. Doctors look at the child’s behavior and development to make a diagnosis. Autism spectrum disorders can sometimes be detected at 18 months or younger. Recent data from CDC’s Autism and Developmental Disabilities Monitoring Network indicate that more children are being identified with autism spectrum disorders than ever before, but they are not being identified as early as they could be. CDC’s "Learn the Signs. Act Early." program has tools to help families track their children’s development. These tools are free and on our website at

Test Your Knowledge

Skills such as taking a first step, smiling for the first time, and waving "bye bye" are called developmental milestones. Children reach milestones in how they play, learn, speak, act, and move (crawling, walking, etc.). A delay in any of these areas could be a sign of an autism spectrum disorder or other developmental disability.

How much do you know about developmental milestones? Take this quiz to find out.

Our Work

CDC’s National Center on Birth Defects and Developmental Disabilities is committed to continuing to provide essential data on autism spectrum disorders, search for risk factors and causes, and develop resources that help identify children with autism spectrum disorders as early as possible. The Autism and Developmental Disabilities Monitoring Network tracks the number and characteristics of children with autism spectrum disorders and other developmental disabilities in diverse communities across the country. By studying the number of people diagnosed with autism spectrum disorders over time, we can find out if the number is rising, dropping, or staying the same. We can also compare the number of children with autism spectrum disorders in different areas of the country and different groups of people. This information is key to promoting awareness of these conditions, helping communities plan and coordinate service delivery, and identifying clues for future research.

CDC’s Study to Explore Early Development (SEED) is currently the largest study in the United States to help identify factors that might put children at risk for autism spectrum disorders and other developmental disabilities. Understanding the risk factors that make a person more likely to develop an autism spectrum disorder will help us learn more about the causes.

CDC's "Learn the Signs. Act Early." program aims to improve the early identification of autism spectrum disorders and other developmental disabilities so children and families can get the early services and support they need. The program provides free resources and tools to help parents and professionals track every child's early developmental milestones and to know how and when to take action on developmental delay.

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