Autism: What Are the Diagnostic Criteria?

When we talk about diagnosis, we’re really talking about the... (drum roll please)... DSM-5.It’s the gold-standard reference in mental health, and the framework that guides official diagnoses.

The DSM-5, published in May 2013 by the American Psychiatric Association (APA), replaced the previous version (DSM-IV, dating from 2000). Its arrival sparked significant controversy within the scientific and professional community working on autism, because it eliminated the old subcategories in favour of a single spectrum with an indication of symptom intensity.

Let’s Talk About Labels

Here, I won’t talk about “severity levels”, because to me, they are largely meaningless.

For forms of autism without intellectual disability, calling someone “mild” often erases their real struggles, while calling someone “severe” can erase their autonomy and capacities. Autism can change a lot depending on the context. So one person might be labeled "mild" in a favorable time of their life, and "severe" in an overloading one.

The Diagnostic Dyad

The complexity of symptom categories in the DSM-IV did little to improve detection — and even less to ensure proper support.

The DSM-5 simplified the approach by consolidating the various factors into two diagnostic pillars, making it easier to identify more autistic profiles without missing subtler ones.

1. Persistent deficits in social communication and interaction across multiple contexts

Including (but not limited to):

1. Deficits in social or emotional reciprocity

2. Deficits in nonverbal communicative behaviours used for social interaction

3. Difficulties developing, maintaining, or understanding relationships

   
   

In other words: this means assessing how well someone understands social codes, interactional contexts, implications, unsaid signals, and facial expressions.

What health professionals are really looking for is the internal experience in these situations — for example: Do you actually enjoy chatting or not? It’s often better to focus on how the person feels, not just how they act — because many autistic people have developed strong compensatory strategies, and may behave in seemingly “typical” ways. But their inner experience tells a different story.

2. Restricted, repetitive patterns of behaviour, interests, or activities, as demonstrated by at least two of the following (currently or in the past):

1. Stereotyped or repetitive movements, use of objects, or speech

2. Inflexibility with change, rigid adherence to routines, or ritualised patterns (verbal or nonverbal)

3. Highly restricted, fixated interests, abnormal in intensity or focus

4. Hyper- or hypo-reactivity to sensory input or unusual interest in sensory aspects of the environment

   
   

This second area is often less masked during evaluations.Things like noise sensitivity, food texture aversions, or difficulty coping with disruptions to routine are usually more visible and easier to articulate.

A Final Note

If you’re in doubt, think of autism like diabetes.If you suspected you had diabetes, you wouldn’t hesitate to get tested. It’s the same for autism.

It’s far better to ask the question and find nothing, than to suffer in silence and slowly harm your mental health without knowing why.