How is autism diagnosed?

6 min read

Autism is way more than how it looks on the outside, but... to be diagnosed, a person has to demonstrate certain behaviors.

And those behaviors are the diagnostic criteria of autism.

In other words, what clinicians look for when assessing for autism.

So if you're trying to understand what autism is, learning about how it's diagnosed is a really good place to start.

You'll also want to find resources that talk about the internal experience and how autism can look when a person learns to mask their traits. (In some cases, making their traits completely invisible on the outside.)

But before you go there, you definitely want to first understand how the field of psychology defines the condition.

This post will help you with that.

Let's start with the two main categories of autism...

1. Social communication challenges, and

2. Restricted repetitive behaviors

From a clinical standpoint, all traits of autism are either related to social communication challenges or restricted repetitive behaviors.

There are 3 traits within the social communication category and 4 within the restricted repetitive behaviors category.

But to be diagnosed, a person doesn't have to show signs of all 7 traits.

They do need to have all 3 of the social communication traits...

But only 2 of the 4 restricted repetitive behaviors traits.

So, let's talk about what the traits actually are.

In the social communication category, the DSM defines the 3 traits like this...

1. Lack of social-emotional reciprocity in conversation

2. Nonverbal communication challenges (mainly eye contact and body language differences), and

3. Relationship difficulties (the examples it includes are not showing interest in peers, difficulty making friends, and difficulty adjusting behavior in social contexts)

And in the restricted repetitive behaviors (RRB) category, the DSM defines the 4 traits like this...

1. Repetitive movements or speech

2. Insistence on sameness, inflexible routines, or ritualized verbal or nonverbal patterns. (This includes extreme distress from small changes, difficulties with transitions, rigid thinking, and the need to eat the same food every day)

3. Restricted, fixated interests, which many autistic people refer to as "special interests," and

4. Sensory over and/or under sensitivities

Again, a person only needs to have 2 of the 4 RRB traits.

So it's possible for an autistic person to NOT have sensory challenges or special interests, for example.

But, for a diagnosis, a person must have all 3 of the social communication traits.

Now, autism does show up differently for everyone.

But there's an important difference within the spectrum of autism that's critical to understand when determining what kind of support an autistic person needs.

And the DSM accounts for this by defining 3 support levels.

Level 1 indicates that a person requires some support.

This is sometimes referred to as low or lower support needs.

This does not mean minimal support needs. It just means lower needs as compared to the other two levels.

People at this level are often able to live independently, but do require some support to not be impaired by their autism.

Support can be mental/emotional, physical... and can come in the form of accommodations.

Level 2 indicates that a person requires substantial support.

This often means that a person can't function in their day to day without someone actively helping them. This is sometimes referred to as medium support needs.

And level 3 indicates that a person requires very substantial support.

This is sometimes referred to as high support needs. This usually means that a person can't live independently and requires around the clock care.

Note that not all diagnosticians assign levels, but this is common practice in the US.

Another helpful way to understand support levels is by reading the following verbiage from the DSM that describes level 1 support needs for the social communication category...

"Without supports in place, deficits in social communication cause noticeable impairments."

So, an autistic person who's impaired *even with* supports in place would be level 2 or 3 as opposed to 1.

For reference, here's the DSM verbiage for level 2 support needs in the social communication category...

"Marked deficits in verbal and nonverbal social communication skills; social impairments apparent even with supports in place."

And for level 3 social communication... "Severe deficits in verbal and nonverbal social communication skills cause severe impairments in functioning"

Now, for a bit of further clarification, the DSM defining these levels doesn’t mean a person who is diagnosed with a level will remain at that level indefinitely.

The DSM actually states otherwise. Here's what it says...

"The severity specifiers may be used to describe succinctly the current symptomatology, with the recognition that severity may vary by context and fluctuate over time."

Now, as I said earlier, the DSM only looks at autism from an observational standpoint and doesn't account for the internal experience at all.

So to understand autism fully, you need to find resources that describe and explain the internal experience as well.