What are Developmental Disabilities and How Common are They?

HandprintsAbout one in six children, ages 3 to 17, are diagnosed with a developmental disability, according to the CDC. Varying in signs and symptoms, developmental disabilities are a group of conditions that begin during the developmental stages of an individual’s life and may affect day-to-day functioning throughout their lifetime due to an impairment in the learning, physical, behavior, or language area.

Developmental disabilities include: 

  • ADHD 
  • Autism Spectrum Disorder 
  • Hearing Loss 
  • Cerebral Palsy 
  • Vision Impairment 
  • Intellectual Disability 
  • Down Syndrome 
  • Fetal Alcohol Syndrome 
  • Learning Disability 
  • Auditory Processing Disorder 
  • Other Developmental Delays 


A developmental disability may first be suspected when a child is not meeting their developmental milestones. These milestones include taking their first steps, responding to their name, waving bye, smiling, and speaking, among others. This list from the CDC categorizes early developmental milestones by age. Developmental delays do not always mean a child has a developmental disability; however, it is important to identify these delays as soon as possible. Research has shown that early identification and intervention can significantly and positively impact a child’s ability to learn new skills and reduce the amount of intervention needed later on in life.  

The exact cause for most developmental disabilities is unknown. It is thought that they are caused by a complex mix of different factors. Genetics, complications at birth, parental health during pregnancy, parental behaviors during pregnancy (like drinking or smoking), infections the baby may have had early in life, and elevated exposure to environmental toxins are just a few of the factors considered.  

People with developmental disabilities can lead very healthy, full lives, and accomplish great things. Famous people with a developmental disability include; 

  • Elon Musk (Asperger’s syndrome, now classified under autism spectrum disorder according to the DSM5) 
  • Simone Biles, U.S. Olympic champion (ADHD) 
  • Madeline Stuart, Model (down syndrome) 
  • Anthony Hopkins, Actor (autism) 
  • RJ Mitte, Actor, of “Breaking Bad” (cerebral palsy) 
  • Daniel Radcliffe, Actor, of Harry Potter Series (dyspraxia) 
  • Dan Harmon, creator of “Community” and “Rick and Morty” (autism) 
  • Adam Levine, Musician (ADHD) 
  • Isabella Springmuhl Tejada, Fashion Designer showcased at London Fashion Week (down syndrome) 
  • Dan Keplinger, Artist (cerebral palsy)   
  • Justin Timberlake, Musician (ADHD) 
  • Lauren Potter, Actor, of “Glee” (down syndrome) 

For more information and resources on Developmental Disabilities visit https://www.aaidd.org/ and https://www.fddc.org/