Thursday, April 26, 2018

New 1 in 59 CDC Autism Prevalence Rates Approach Reality

Shannon Des Roches Rosa

Today the CDC released new autism prevalence numbers of 1 in 59, or 1.7%. As we wrote in 2014 after the CDC adjusted its autism prevalence rate to 1 in 68, it's important to keep calm and think critically about what these readjusted numbers actually mean:
  • We are getting better at finding and diagnosing autistic kids. This is good news. As the CDC press release states, "Autism prevalence among black and Hispanic children is approaching that of white children." This means that more autistic kids who need support will have the opportunity to get it.
  • Many researchers and experts have long considered the CDC's estimated autism prevalence rates to be too low, and consider the 1 in 38 estimate from a 2011 study of autism prevalence in South Korea to be more realistic.
  • This is not evidence of some sort of "autism epidemic." Much of the increased autism prevalence rate in the past four decades—from autism being considered "rare," to nearly everyone knowing or being related to an autistic person—is due to both widened diagnostic criteria for autism, and diagnositic substitution (intellectual disability diagnoses decreasing at the same time autism diagnoses increase, for example). 
Additional findings from the CDC Report, per the press release:
The latest estimate of  1.7 percent (1 in 59) is higher than the previous ADDM estimate released in 2016, which found a prevalence of 1.5 percent or 1 in 68 children. Some of the change in prevalence could be due to improved autism identification in minority populations – although autism is still more likely to be identified in white children than in black or Hispanic children. 
About 1 in 59 eight -year-old children in 11 communities across the United States were identified as having autism in 2014, according to a report published today in CDC’s Morbidity and Mortality Weekly Report (MMWR) Surveillance Summary.
  • The data demonstrate that more work needs to be done to identify children with autism at a younger age and refer them to early intervention:
  • Fewer than half of the children identified in the Autism and Developmental Disabilities Monitoring Network received their first autism diagnosis by the time they were 4 years old.
  • Although 85 percent of children with autism had concerns about their development noted in their health records by the time they were 3 years old, only 42 percent received a developmental evaluation by that age.
  • This lag between first concern and first evaluation may affect when children with autism can begin getting the services they need.
What this report demonstrates most clearly is that "autistic people—of all ages, races, and genders–have always been here"; we just need to get better at finding them. It's important to also note that the CDC data do not include autistic adults, and the agency has yet to do such a survey. However a 2012 report from the United Kingdom estimated adult autism prevalence at 1.1%, and the U.S. rate is unlikely to be much different. As The Autistic Self Advocacy Network stated after the 2014 CDC prevalence announcement:
“The lack of any data on adults represents a serious gap in CDC’s efforts. When the United Kingdom conducted an adult prevalence study, it found the same rate of autism in adults as children, helping to debunk public hysteria over a so-called ‘autism epidemic’.” 
The CDC's adjusted prevalence rate will probably still be criticized by those unfamiliar with the contributing factors above. Non-autistic people aged 40 and older frequently make assumptions such as, "we never had autistic kids in my school" and "I never knew anyone autistic growing up," when what is more likely is that they went to school with and knew plenty of autistic people who were undiagnosed—and who typically had to survive a lifetime of bullying and other abuse without appropriate supports or any understanding. They probably also never met high-support people like my teenaged son, because in previous generations disabled children with the highest support needs were usually either automatically institutionalized or hidden away at home, and so never had a chance to become part of their communities.

I am glad the CDC's autism prevalence rates are becoming more realistic, and hope wider understanding of what this data adjustment means will leader to more autism acceptance, as well as better autism services. I am also grateful to live in an era in which autistic and disabled advocates are, in parallel to these adjustments, demanding visibility and rights for autistic people of all abilities. My hope is that having better autism estimates plus wider autism understanding means my son won't get left behind by society—both now, or after I'm gone.

[image: Selfie of the author and her teenaged autistic son,
hiking on a sunny, grassy hillside.]