If you or your child is preparing for an ADOS-2 assessment for autism, you may have come across different module numbers and wondered which one will be used – and what that choice means.
In particular, the difference between ADOS-2 Modules 3 and 4 is often queried. Many people assume that the module number represents the suspected level or severity of autism. But that’s not how ADOS-2 modules work.
Modules are simply different versions of the assessment, each designed to suit different age groups and developmental stages.
Both Module 3 and Module 4 are designed for people who use fluent speech. But there are important differences in exactly who they’re each used for, and what happens during each assessment.
Here, we’ll explain those differences, how clinicians decide which module to use, and what the module number does – and doesn’t – tell you about the results.
Does a higher ADOS module mean more severe autism?
This is one of the biggest misconceptions, and so one of the main things to understand about ADOS-2 modules.
A higher ADOS-2 module number does not mean more severe autism.
The different modules simply allow clinicians to use assessment activities that are most appropriate for each person – based on their communication skills, age, and developmental stage.
Generally speaking, Modules 1 and 2 are designed for children who aren’t yet using fluent speech, while Modules 3 and 4 are for people who are verbally fluent.
This is why the difference between Modules 3 and 4 in particular can be confusing, as both are designed for fluent speakers – which includes children as well as adults being assessed for autism.
So, if the Module numbers don’t indicate severity, what is the difference between ADOS-2 Module 3 and Module 4?
ADOS-2 Module 3 vs Module 4: the differences at a glance
Module 3 and Module 4 are both designed for people who communicate using fluent speech. The main difference is the age and developmental stage they’re designed for, which means the activities and conversations used during each module are different.
| ADOS-2 Module 3 | ADOS-2 Module 4 | |
| Language level | Fluent speech | Fluent speech |
| Typical age/stage | Children and younger adolescents, generally under 16 | Older adolescents and adults, generally age 16+ |
| Assessment style | Conversation combined with structured, interactive, and imaginative activities | Greater emphasis on conversation and interview-style activities |
| Common topics | School, friendships, emotions, interests, and everyday social experiences | Relationships, education or work, independence, emotions, and adult social experiences |
| How it’s chosen | Language level, age, and developmental appropriateness | Language level, age, developmental appropriateness, and independence |
| Does it indicate autism severity? | No | No |
The most important difference for parents and people preparing for an assessment is therefore not what the clinician is looking for, but how they look for it.
Both modules create structured opportunities to observe social communication, reciprocal interaction, and restricted or repetitive behaviors associated with autism. But the activities used to do this need to make sense for the person being assessed. A school-age child and a 30-year-old adult naturally have very different social experiences, relationships, responsibilities, and ways of interacting.
Modules 1 and 2 follow the same basic principle but are designed for children at earlier stages of spoken language development. You can read more about what to expect during each of the ADOS-2 modules in our complete guide.
What happens during ADOS-2 Module 3?
ADOS-2 Module 3 combines relaxed conversation with a series of structured activities designed to create natural opportunities for your child to communicate, interact, tell stories, explain ideas, and talk about their experiences.
This often involves them being encouraged to:
- Describe or create a story using pictures, objects, or books.
- Talk about school, friendship, and their interests.
- Discuss emotions and situations that make them feel happy, angry, anxious, or sad.
- Describe everyday social situations or difficulties they have experienced.
- Engage in simple problem-solving or imaginative scenarios.
- Take part in other interactive activities with the clinician.
Throughout the session, the clinician isn’t looking for “correct” answers. Instead, the activities give them opportunities to observe how your child communicates and interacts, including behaviors and characteristics that can be relevant to an autism diagnosis.
For example, they may observe how easily conversation flows back and forth, how your child shares information or responds to another person’s thoughts and experiences, how they use eye contact, facial expressions, and gestures alongside speech, and how they talk about emotions and relationships. These conversations will also give the clinician the opportunity to observe whether there are other specific behaviors or patterns that are often characteristic of autism.
Essentially, an ADOS-2 Module 3 assessment usually feels more like a conversation with interactive activities, rather than a formal clinical test.
There’s nothing your child needs to study or practice beforehand. In fact, the aim is for the clinician to see how they naturally communicate and respond.
What happens during ADOS-2 Module 4?
ADOS-2 Module 4 is designed for verbally fluent older adolescents and adults.
Because the person being assessed is older, Module 4 typically places greater emphasis on conversation and discussion than the earlier modules. The topics also reflect the social experiences, relationships, and responsibilities that become more relevant during later adolescence and adulthood.
For example, during a Module 4 assessment, the clinician may ask the person being assessed about things such as:
- Friendships and other relationships.
- Education, employment, or experiences in the workplace.
- Emotions and how they recognize or manage them.
- Social situations they find easy or difficult.
- Independence and everyday life.
- Their interests and routines.
- Plans, goals, and thoughts about the future.
There are also structured activities within Module 4, so it isn’t simply an informal conversation or standard clinical interview.
As they talk and work through the different activities, the clinician is observing aspects of social communication and interaction – including how conversation develops, how they describe relationships and emotions, their use of nonverbal communication, and how they understand and respond to different social situations. They’ll also consider restricted or repetitive patterns of behavior or interests that emerge during the assessment.
In other words, the broad purpose is similar to Module 3. The difference is that Module 4 creates opportunities to observe these characteristics through conversations and situations that are more relevant to an older adolescent or adult.
How do clinicians choose between ADOS-2 Module 3 and Module 4?
You don’t need to decide which ADOS-2 module you or your child should have. The clinician administering the assessment will determine which module is most appropriate.
There are several things they’ll consider.
Language ability
Both Module 3 and Module 4 are intended for people who use fluent speech. If someone isn’t yet communicating at this level, a different ADOS-2 module may be more appropriate – regardless of their age.
Age
Module 3 is generally used with children and younger adolescents, while Module 4 is generally used from around age 16 into adulthood.
For many people, this makes the choice relatively straightforward. A verbally fluent 12-year-old, for example, would typically complete Module 3, while a verbally fluent 20-year-old would typically complete Module 4.
Developmental appropriateness
There can be more consideration involved during adolescence, particularly as someone approaches the age at which Module 4 becomes appropriate.
A verbally fluent 14-year-old would generally still complete Module 3, even if they appear mature for their age. For an older adolescent, the clinician can consider whether Module 3 or Module 4 provides the most developmentally appropriate way to explore their social experiences.
Factors such as independence, interests, relationships, and the relevance of adult-focused questions and activities can all help inform this decision.
But the choice of module doesn’t suggest a higher likelihood of autism or more severe autism. It’s simply about choosing the module that is most appropriate for the person’s communication skills, age, and developmental stage, and that gives the clinician the best opportunity to make meaningful observations.
Ultimately, clinicians aren’t trying to select the “highest” module someone can complete. They’re choosing the assessment that gives them the best opportunity to understand that particular person’s social communication and behavior.
Is ADOS-2 Module 4 the same as Level 3 autism?
No. This is another common point of confusion, but ADOS-2 modules and autism support levels are completely separate things.
The ADOS-2 Modules, as explained above, are different versions of the assessment, chosen based on the person’s language ability, age, and developmental stage.
Autism levels, on the other hand, are used within the DSM-5 diagnostic framework to describe the level of support a person with autism requires. So this comes after the autism assessments and forms part of a diagnosis, but is not linked to the ADOS-2 module number used during their assessment in any way.
The simplest way to remember the difference is that modules describe the assessment; support levels describe support needs.
Does the ADOS-2 module chosen affect your results?
Module 4 isn’t “harder” than Module 3, or any other module. So results aren’t impacted by the module used or the “answers” given.
They are all assessing the same thing, just using different activities and methods, to ensure each assessment is best suited to the person being assessed.
This also means that you can’t simply compare the scores of two people who completed different modules to determine who has more significant autism characteristics or greater support needs.
Most importantly, it’s important to remember that ADOS results are never used on their own to diagnose autism.
The ADOS-2 is one of the most widely used standardized observational assessments for autism, but it forms just one part of the wider diagnostic process. Clinicians consider what they observe during the ADOS alongside other important information, which may include developmental and medical history, interviews with parents or other relevant people, questionnaires or additional assessments, and their professional clinical judgment.
Together, this information provides a much more complete picture than any single ADOS-2 score or module could provide.
ADOS-2 assessments at REACH Behavioral Health
If you think you or your child may be autistic, you don’t need to know which ADOS-2 module you need before seeking an evaluation.
At REACH Behavioral Health in Ohio, we provide autism evaluations for children, adolescents, and adults across the state. Our experienced clinicians use the appropriate assessment tools for each individual and consider the results as part of a wider evaluation designed to build a complete picture of their development, experiences, and needs.
We understand that seeking an autism assessment can come with a lot of questions – whether you’re a parent trying to understand your child’s behavior or an adult who has spent years wondering whether autism could explain aspects of your own experiences.
Our team is here to help you understand the assessment process, what your results mean, and what comes next.
Contact us to book an ADOS-2 consultation and learn more about autism evaluations at REACH Ohio.