Why Autism Diagnoses Are Delayed

Autism spectrum disorder (ASD) affects people in different ways. Some show obvious signs from early childhood, while others seem to “grow into” their diagnosis over time. In fact, delayed or missed diagnoses are quite common.

According to the Centers for Disease Control and Prevention (CDC), the average age for an ASD diagnosis is around 4 years old. However, diagnoses after age 4 are not unusual.

This article will explore the top reasons why many people don’t receive an autism diagnosis until later in life.

Why Autism Diagnoses Are Delayed
Why Autism Diagnoses Are Delayed

Academic Performance Can Mask Signs of ASD

Many undiagnosed autistic children perform well in school academically. Their intelligence helps them compensate socially, so their autism traits go unnoticed.

Parents and teachers look for alternative explanations when these kids show unusual behaviors. Even experienced pediatricians miss the diagnosis if a young child communicates verbally and meets the typical developmental milestones.

A child’s academic strengths can help them thrive in elementary school despite minor social or behavioral issues. However, as coursework becomes more demanding in middle and high school, classic signs of ASD often emerge:

  • Rocking
  • Lack of eye contact
  • Obsessive interests
  • Inflexible routines
  • Sensory sensitivities

At this point, autism may be mislabeled as anxiety, depression, or general social maladjustment.

In adulthood, major life changes like college graduation, new jobs, or parenthood can unveil previously hidden ASD characteristics.

Early Misdiagnoses Are Common

By age 4, most autistic children are accurately diagnosed. After this point, the risk of misdiagnosis rises significantly.

Some frequent early misdiagnoses include:

  • ADHD
  • OCD
  • Social anxiety disorder
  • Separation anxiety

According to a 2019 study, 10% of autistic adults were misdiagnosed with ADHD as children. Another 12% with childhood ADHD were later found to be autistic.

The older a person gets before diagnosis, the less likely autism will be recognized. This happens because the symptoms drift further from the conventional profile.

Changing Criteria Complicates Diagnosis

The diagnostic criteria for autism spectrum disorder (ASD) changed significantly in 2013 with the publication of the DSM-5 diagnostic manual.

Previously, subtypes like Asperger’s syndrome and PDD-NOS existed. But with the DSM-5, these were folded under the umbrella diagnosis of ASD.

Some individuals lost access to care because their previous diagnosis was eliminated. Only later in life did they seek a new evaluation and ASD diagnosis.

This also means that people evaluated under old diagnostic standards may not have qualified at the time. But today’s broader, more inclusive criteria may now apply.

Sex and Gender Bias Delay Diagnosis

Multiple studies show autistic females are far less likely to be diagnosed than males. Sex and gender biases play a huge role in this discrepancy.

However, research also suggests genetic and developmental factors give females natural advantages when it comes to social communication. This so-called “female protective effect” likely allows many autistic girls to fly under the radar.

Additionally, certain autism traits may be more obvious or problematic in males versus females. For example:

  • Weak motor skills may raise red flags for boys who play sports, but not for girls who don’t.
  • Shyness and quietness may seem natural for girls but concerning for boys.

Gender roles and expectations tend to minimize autism traits in girls and women. This delays diagnosis and support.

Socioeconomic Status Impacts Diagnosis

In the United States, race and income affect healthcare access across the board, including autism diagnosis.

According to a 2021 study, children of color are diagnosed later than white children, if at all. Specifically:

  • Black autistic children are 2.6 times more likely to be undiagnosed.
  • Hispanic and Asian children are also less likely to be diagnosed.

Cultural misconceptions play a role. For example, one study found Black parents report less concern about autism traits than white parents. Lower awareness in minority communities leads to later diagnosis.

Language barriers also contribute to lower diagnosis rates among Hispanic and Asian children.

Overall, systemic racial biases combined with socioeconomic factors delay diagnosis for minorities.

Is a Late Diagnosis Worthwhile?

There are certainly benefits to diagnosing autism early. But later diagnoses still have immense value.

The biggest barrier is often convincing doctors to recognize symptoms in older children or adults. Many fear stigma or being dismissed by providers.

But research shows that for most, the positives of an autism diagnosis outweigh the negatives. It can bring relief and validation after years of unanswered questions.

Later diagnosis also opens the door to helpful treatments and support, like:

  • Applied behavior analysis (ABA)
  • Cognitive behavioral therapy (CBT)
  • Medications for co-occurring conditions
  • Accommodations at school or work
  • Social skills training
  • Specialized job coaching

While early intervention matters, an autism diagnosis at any age can vastly improve quality of life.

Signs of Autism in Adults

In case you or a loved one relate to this article, below are common autism traits in adults:

  • Social anxiety
  • Bluntness or lack of tact
  • Poor eye contact
  • Few close friendships
  • Missing social cues
  • Alexithymia – difficulty identifying feelings
  • Specialized interests
  • Rigid routines and timetables
  • Discomfort with change
  • Noticing details others miss
  • Sensory sensitivities
  • Preferring to be alone

If these resonate, don’t write them off as personality quirks. Consider exploring an evaluation, even as an adult. Diagnosis and support can change lives.

ABA Therapy Provides Critical Early Intervention

While late diagnosis has value, early intervention is ideal. The best approach for young autistic children is applied behavior analysis (ABA) therapy.

ABA uses positive reinforcement to build communication, social, academic, and adaptive skills. It’s the only scientifically proven method to prepare children with autism for success in school and beyond.

Jade ABA Therapy provides top-quality, compassionate ABA for kids in Maryland. Their experienced clinicians help each child reach their full potential. They also guide and empower families through the journey.

To get started with in-home ABA therapy that will help your child thrive, call Jade ABA today at (410) 616-0901. Or learn more on their website at www.jadeaba.org. Don’t wait to get the support your child deserves.


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