What has Contributed to the Increased Number of Autism Diagnoses?

You see a lot of articles and stories about the growing number of autism diagnoses. According to the CDC, in 2020, 1 in 34 8-year-old children in MN have autism spectrum disorder compared to 1 in 44 8-year-old MN children having ASD in 2018. And if you go back a little further, the increasing numbers are even more alarming.  

But what has led to these rising numbers isn’t an easy or simple answer. Several factors have likely contributed to the increasing population of people with autism. Beyond the hyperbole, here is what you should know about the rising autism numbers.

Autism definitions have changed

As medical professionals have learned more, the definition and view of autism has changed. In the past, children were often misdiagnosed or treated for other conditions, leaving many languishing in institutions where they didn’t receive the proper support or medication. This group of people has become known as the “lost or missing generation.” Spectrum News states, “In the 1950s and 1960s, thousands of children who had autism were either completely missed or were saddled with the wrong label. The word ‘autism’ wasn’t included in the ‘Diagnostic and Statistical Manual of Mental Disorders,’ the main reference book for psychiatry in the U.S., until 1980.”

Further, Spectrum News states, “Autism was originally described as a form of childhood schizophrenia and the result of cold parenting, then as a set of related developmental disorders, and finally as a spectrum condition with wide-ranging degrees of impairment. Along with these shifting views, its diagnostic criteria have changed as well.” Autism used to be divided into categories like pervasive developmental disorder-not otherwise specified (PDD-NOS), Asperger’s syndrome and autism.

“Looking at past numbers compared to current numbers, one of the challenges is that you’re comparing different classifications of different symptoms,” says Fraser Psychologist Jessica Dodge. “Those with those former diagnoses, like Asperger’s syndrome, now fall under the autism spectrum, which contributes to more people being diagnosed with autism.”

Changing attitudes about autism and intellectual disability

In the past, more children with intellectual disabilities were diagnosed with autism. According to the “Prevalence and Disparities in the Detection of Autism Without Intellectual Disability” article in Pediatrics, “Before 2000, estimates suggested up to 75% of ASD children had ID[intellectual disability]. Recent studies report that 30% to 40% of ASD children have ID [intellectual disability], indicating better identification of children with ASD without ID [intellectual disability].” Healthcare professionals now realize that people with autism can have an average or above-average IQ. At the same time, children without an intellectual disability were also less frequently diagnosed with autism, says Dodge. That’s because these children weren’t having delays in school, didn’t need an individualized education plan (IEP) and didn’t need other services like speech therapy. Since these children were better able to cope without those supports, they often went without receiving a diagnosis.

“In addition, some children who were previously diagnosed with an intellectual disability may also have a co-occurring autism diagnosis,” says Dodge.

In other words, some children with autism weren’t diagnosed because they didn’t require as much support; some children who had autism were diagnosed only with an intellectual disability and intellectual disability was formerly believed to co-occur more commonly with autism, which also contributed to fewer children being diagnosed with ASD.

More adults are getting diagnosed

Some children who weren’t diagnosed are now adults seeking autism diagnoses. This is partly because there is more awareness about autism. Some of that comes from other adults speaking about autism and neurodiversity on social media. Increased awareness also comes from organizations like Fraser conducting autism research, sharing autism findings and hosting events focused on raising autism awareness. Some adults also seek an autism diagnosis after their child is diagnosed with autism, as they recognize some of the same signs in themselves.

“We’re also learning more about what autism can look like in adults,” says Dodge. “Suddenly, there is a name for some of the challenges they’re experiencing. They may be struggling to keep a job, make friends or be independent financially. As they’re struggling to meet those milestones, they wonder why. Then they see a social media post, and it clicks.” 

Diagnostic tools have improved

Along with a better understanding of autism, diagnostic tools have improved over the years. It wasn’t until 1998 that the Autism Diagnostic Observation Schedule (ADOS) was created and used. According to PubMed.gov, “The Autism Diagnostic Observation Schedule-Generic (ADOS-G) is a semistructured, standardized assessment of social interaction, communication, play, and imaginative use of materials for individuals suspected of having autism spectrum disorders.” This screening marked a turning point because it used direct interaction and observation by mental health professionals.

Dodge says more pediatricians have also begun using the Modified Checklist for Autism in Toddlers (M-CHAT) at a well-child check. According to M-ChatScreen.com, “The M-CHAT-R/F is a 2-stage parent-report screening tool to assess risk for autism spectrum disorder (ASD).” The universal screening helps identify red flags early on, so autism can be diagnosed in younger children.

Telehealth options have decreased some barriers

According to the “Prevalence and Disparities in the Detection of Autism Without Intellectual Disability” article in Pediatrics, “Children residing in affluent areas were 80% more likely to be identified with [autism without intellectual disability] ASD-N compared with children in underserved areas,” the truth is that families in more affluent areas have more access to clinicians and assessments because there are more providers in these areas, says Dodge. Autism evaluations are also expensive, so a family without insurance may be unable to afford an assessment.

“Also, if both parents work, it can be hard to take off time to get an evaluation,” says Dodge. “They may also not have access to reliable transportation or are caregivers for family members with other medical conditions.”

However, during the beginning of the pandemic, many healthcare providers quickly had to adapt to offer telehealth options. Autism assessments were also adapted for telehealth. Telehealth evaluations have provided more access for families who struggled to access evaluations due to a lack of providers in their area, unreliable transportation or their inability to leave home. This has also contributed to more children being able to get a diagnosis.

As multiple barriers decrease, more children of color will be diagnosed

Historically, Black people have often been misdiagnosed for physical and mental health issues. The American Psychiatric Association states, “Rates of mental illnesses in African Americans are similar with those of the general population. However, disparities exist in regard to mental health care services. Only one-in-three African Americans who need mental health care receives it. Compared with whites with the same symptoms, African Americans are more frequently diagnosed with schizophrenia and less frequently diagnosed with mood disorders.” For Black parents seeking a diagnosis for their child, says Dodge, their concerns are too often ignored or minimized. This is compounded when their child doesn’t have significant delays in development. Since the symptoms are less obvious, Black parents are even more likely to be dismissed.

However, the increased understanding of autism without intellectual disability will also lead to more diagnoses of Black and Hispanic children. According to the “Prevalence and Disparities in the Detection of Autism Without Intellectual Disability” article in Pediatrics, “As identification of [autism without intellectual disability] ASD-N improves, particularly among Black and Hispanic children, continued increases in ASD prevalence are likely.” While this study supports that more Black and Hispanic children will receive an autism diagnosis, it’s important to acknowledge this historical bias, and for healthcare providers to remain cognizant of it. They must learn to listen to a parent’s concerns, which may reveal some less obvious signs of autism that shouldn’t be ignored.

There are other cultural barriers for an autism diagnosis. For example, in Minnesota there is a large Somali population. English may not be the primary language spoken in the home. To raise autism awareness and make services and resources available to these communities, websites, videos and forms about autism must be translated into multiple languages. This has started to happen more often, says Dodge.

The Minnesota Department of Human Services (MN DHS) has many autism resources translated into Hmong, Karen, Oromo, Russian, Somali, Spanish and Vietnamese. You can access some of that translated information on their Pathway to Services and Supports page. The University of Minnesota also provides some helpful resources like, “‘On the Autism Spectrum: Families Find Help and Hope,’ a series of five short films that raise awareness and understanding of autism spectrum disorder (ASD) and services available to Minnesota families within the following communities: African American, Hmong, Latino, Native American, and Somali.” Fraser.org also has an accessibility widget that translates the text into other languages and offers larger text, a screen reader, dyslexia-friendly text and sensory-friendly modifications.

The increasing number of people being diagnosed with autism can’t be attributed to one thing. Rather — changing definitions of autism, shifting beliefs about autism and intellectual disability, more adults getting diagnosed, increased awareness of autism, improved diagnostic tools, more telehealth options, and increased support for non-English speakers — have contributed to the increase of autism diagnoses. While having autism can present challenges, being misdiagnosed or undiagnosed presents a far greater risk of lifelong issues. Experts agree that early autism intervention leads to better outcomes for children throughout their lives.