What Are The DSM-5 Diagnostic Criteria For Autism Spectrum Disorder?

It's not referred to as the "psychiatry bible" for nothing — the diagnostic and statistical manual of mental disorders, published by the American Psychiatric Association, holds a wealth of information. It lists, for each of the almost countless disorders related to mental health and cognitive functioning, details about prevalence, risk factors, other diagnoses that may better explain symptoms, information about how a disorder develops, and insights into prognosis.

It's also where medical professionals in the United States will find the diagnostic criteria that ultimately allow them to decide whether or not a person has a certain disorder. 

A. 'Persistent deficits in social communication and social interaction'

The DSM-5's diagnostic criteria for autism spectrum disorder are separated into categories that go from A to E, and some of which also contain their own  sub-categories. The first bit, A, demands that to be diagnosed with autism spectrum disorder, a person has to face ongoing challenges in social communication and interaction with other people, in different areas of life such as at school, work, and in the family. These challenges may be current or past. 

It goes on to offer up examples, which it says don't cover the full spectrum of possibilities (paraphrased for increased clarity and in a bid to avoid wordings that autistic people may rightfully experience as offensive):

• Challenges in social relationships — such as trouble understanding when people expect you to start a conversation, a hard time knowing when or how to respond, not being sure how to share and discuss interests and feelings, and difficulty figuring out how people without autism expect back-and-forth conversations to work.
• A very different style of non-verbal communication, a kind of communication that can cover anything from body language to tone and volume of voice and eye contact. 
• More challenges in social relationships — trouble adjusting behavior to suit context (sometimes known as "code-switching"), not much interest in same age peers, not engaging in imaginative play and difficulty making friends or maintaining friendships. (Remember, autism can be diagnosed in children and adults alike, and some of these examples pertain to kids). 

B. 'Restricted, repetitive patterns of behavior, interests, or activities'

This second category, the DSM-5 says, has to be demonstrated by at least two of the examples they go on to list, either now or in the past. 

• Repetitive physical movements (known as "stimming" in the autistic community), echolalia (repeating words or phrases people say), or lining objects up. 
• A strong need for routine or "sameness", including distress when something suddenly changes. The DSM-5 offers eating the same foods repeatedly and taking the same route as examples. 
• "Highly restricted and fixated interests", also popularly known as special interests, obsessions, or in the autistic community simply "passions". Autistic people are well-known to become extremely interested in particular topics, about which they become incredibly knowledgeable and keep exploring more. 
• Being more sensitive or less sensitive than other people to certain stimuli. This may include very negative and distressing reactions to loud sounds or bright lights, or not being so sensitive to pain or temperature changes. (These are examples. The actual things an autistic person is more or less sensitive to will vary greatly.)

The DSM-5 further details that the professionals making the diagnosis should specify the severity of these traits.

C. Symptoms appear early in life

Though the DSM-5 doesn't require a person to be identified as autistic during childhood to "qualify" for a diagnosis of autism spectrum disorder, it does say that a person should have had the characteristics associated with ADS during early childhood. These traits, the document says, may become masked later in life as a person learns strategies that help them pass as non-autistic in some cases. 

D. 'Significant impairment'

To be diagnosed with autism spectrum disorder, a person can't just have the traits or symptoms listed in categories A and B — these symptoms should also cause "significant impairment" in the person's life or daily functioning. These difficulties can manifest in social, work, educational, or other contexts. 

E. Ruling out other explanations

Once all these other diagnostic criteria are met, it's also important for a diagnosing medical professional to exclude other causes. These include intellectual disability and global developmental delay. A person can, however, be diagnosed with both autism and another diagnosis listed within the DSM-5. 

But wait, there's more: Specifiers listed in the DSM-5

Autism can be diagnosed:

• With or without intellectual impairment.
• With or without language delays. 
• As associated with other medical, genetic, or environmental factors.
• As associated with other mental, developmental, or behavioral disorders.
• With "catatonia", a group of symptoms denoted by little movement, communication, and stupor. 

Levels of autism

An autism diagnosis further comes in various "levels", which broadly describe how much support a person needs to function optimally and how intensely they are affected by the symptoms listed in the diagnostic criteria. 

• Level 1 — "requiring support". Without that support, the DSM-5 specifies, the person might be able to communicate in full sentences, but in such a way that they may come across as (and yes, I quote) "odd and typically unsuccessful". The person may have a hard time making friends. Rigid behaviors and difficulties with multitasking can impair daily functioning.
• Level 2 — "requiring substantial support". The wording is similar as for level 1, except the person now doesn't just have "deficits", but "marked deficits". The inflexible behaviors associated with autism are often immediately apparent to other people and changes can lead to significant distress.
• Level 3 — "requiring very substantial support". At this point, a person experiences "severe deficits" in social interaction and communication, has extremely inflexible behaviors, and suffers extreme distress in response to routine or other changes.