Tiktok Instagram Facebook-f Linkedin
Book Appointment

Table of Contents

Autism and ADHD Together: Understanding Dual Diagnosis

Autism and ADHD Together: Why Dual Diagnosis Is More Common Than You Think

For many years, autism and ADHD were treated as entirely separate conditions. Clinicians were often trained to diagnose one or the other, and families were left trying to make sense of challenges that didn’t fully fit into a single explanation. At Rocky Mountain Psychological Services (RMPS), we often hear from parents who feel that while a diagnosis helped, it didn’t tell the whole story.

That’s because it often doesn’t. Research now shows that autism and ADHD frequently occur together, and recognizing this overlap is essential. A dual diagnosis provides a more accurate understanding of how a child learns, behaves, and interacts with the world, leading to more effective support.

How Common Is Autism and ADHD Together?

The overlap between autism and ADHD is more common than many expect. Studies estimate that between 30% and 80% of individuals with autism also meet criteria for ADHD (Leitner, 2014). Similarly, a significant portion of children diagnosed with ADHD show traits associated with autism (Ronald et al., 2008).

This shift in understanding was formally recognized with the DSM-5 (American Psychiatric Association, 2013), which allows both conditions to be diagnosed together. Prior to this, many children were diagnosed with only one condition, even when both were present.

In clinical practice, this means that what once seemed like a “complicated” or “unclear” profile is now better understood as a common neurodevelopmental pattern.

Why Do Autism and ADHD Overlap?

The connection between autism and ADHD is rooted in how the brain develops. Research has shown overlapping genetic and neurological factors, particularly in areas responsible for attention, executive functioning, and regulation (Rommelse et al., 2010).

Rather than being entirely separate, these conditions are increasingly viewed as part of a broader neurodevelopmental spectrum. This helps explain why children may show traits of both conditions at the same time, rather than fitting neatly into one category.

Where the Confusion Happens

One of the biggest challenges in identifying a dual diagnosis is that autism and ADHD can look similar on the surface, even when the underlying causes differ. For example, a child who struggles with attention may be easily distracted, which is common in ADHD, or may be deeply focused on specific interests and struggle to shift attention, which is more consistent with autism.

There are several areas where overlap commonly creates confusion:

  • Attention difficulties: Distractibility in ADHD versus hyper-focus or difficulty shifting attention in autism
  • Impulsivity: Acting without thinking in ADHD versus responses influenced by sensory or social processing differences in autism
  • Social challenges: Difficulty maintaining interactions in ADHD versus differences in understanding social cues in autism
  • Emotional regulation: Intense reactions and difficulty calming down in both conditions

Because of these similarities, it is easy for one diagnosis to overshadow the other, especially without a comprehensive evaluation.

Why Dual Diagnosis Is Often Missed

Even with growing awareness, dual diagnosis is still frequently overlooked. In many cases, one set of symptoms is more noticeable and becomes the focus of diagnosis, while the other is less recognized.

Some of the most common reasons include:

  • Symptom masking, where traits of one condition hide the other
  • Developmental timing, with ADHD often identified earlier and autism traits becoming clearer later
  • Diagnostic bias, where clinicians focus on the most prominent behaviors
  • Outdated frameworks, which historically discouraged diagnosing both conditions together

These factors can delay accurate identification, sometimes for years.

Why Accurate Diagnosis Matters

Recognizing both autism and ADHD allows for a more complete understanding of a child’s needs. Without this clarity, support strategies may only address part of the challenge, leading to frustration and limited progress.

Children with co-occurring autism and ADHD often benefit from support that addresses multiple areas at once. This may include:

  • Building executive functioning skills such as organization and task completion
  • Supporting social communication and peer interaction
  • Developing emotional regulation strategies
  • Creating structured and predictable environments

Research suggests that children with dual diagnosis often have more complex profiles and benefit from individualized intervention approaches (Jensen & Steinhausen, 2015).

For families, an accurate diagnosis often provides relief. It explains why certain strategies may not have worked and offers a clearer path forward.

The Role of Comprehensive Assessment

At RMPS, we emphasize a thorough and evidence-based assessment process when autism and ADHD are both being considered. Because the overlap can be subtle, it is important to understand not just what behaviors are present, but why they are occurring.

A comprehensive evaluation typically includes multiple components, such as:

  • Clinical interviews with parents
  • Standardized cognitive and behavioral testing
  • Observations across different settings
  • Input from teachers or other caregivers

The American Academy of Pediatrics (2019) highlights that this type of in-depth assessment is essential for accurately identifying overlapping neurodevelopmental conditions.

Supporting Children with Autism and ADHD

Children with a dual diagnosis can thrive when their support reflects the full picture of their needs. Structure and consistency play an important role, helping reduce both inattentiveness and anxiety. At the same time, targeted strategies can help build skills in areas like emotional regulation and executive functioning.

Effective support often includes:

  • Clear routines and predictable expectations
  • Visual supports to aid organization and transitions
  • Breaking tasks into smaller, manageable steps
  • Teaching coping strategies for emotional regulation

Equally important is recognizing strengths. Many children with autism and ADHD demonstrate creativity, curiosity, and unique problem-solving abilities. These strengths should be supported alongside their challenges.

A Strength-Based Perspective

At RMPS, we believe it is essential to move beyond a deficit-focused view of autism and ADHD. These are not simply conditions to be fixed, but different ways of thinking and experiencing the world.

When children are understood and supported appropriately, they can build confidence, develop their strengths, and succeed in meaningful ways. A dual diagnosis does not limit potential it clarifies how to support it.

Final Thoughts

The recognition of Autism and ADHD as a dual diagnosis represents an important shift in how we understand neurodevelopment. For many families, it brings clarity after years of uncertainty.

If a child’s current diagnosis does not fully explain their challenges, it may be worth exploring whether both conditions are present. At Rocky Mountain Psychological Services, we are committed to helping families gain that clarity through comprehensive, thoughtful assessment.

Understanding the whole child is the foundation for meaningful support and lasting progress.

References

  • American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (DSM-5).
  • Antshel, K. M., & Russo, N. (2019). Autism spectrum disorders and ADHD: Overlapping phenomenology, diagnostic issues, and treatment considerations. Current Psychiatry Reports, 21(5).
  • Jensen, C. M., & Steinhausen, H. C. (2015). Comorbid ADHD in autism spectrum disorders. European Child & Adolescent Psychiatry, 24(2), 151–160.
  • Leitner, Y. (2014). The co-occurrence of autism and ADHD. European Child & Adolescent Psychiatry, 23(6), 449–457.
  • Ronald, A., Simonoff, E., Kuntsi, J., et al. (2008). Evidence for overlapping genetic influences on autistic and ADHD behaviours. Journal of Child Psychology and Psychiatry, 49(5), 535–542.
  • Rommelse, N. N. J., Geurts, H. M., Franke, B., et al. (2010). A review on cognitive and brain endophenotypes in autism and ADHD. Neuroscience & Biobehavioral Reviews, 35(3), 941–969.
  • American Academy of Pediatrics. (2019). ADHD: Clinical practice guideline for the diagnosis, evaluation, and treatment of ADHD in children and adolescents.
Book Appointment

We are here to assist you

Leave your contact info and someone will reach you shortly.

MacKenzie Ebel

MacKenzie is a Psychometrist/Psychological Assistant at RMPS. She completed her Bachelor of Arts in Psychology at Princeton University, where she also played 4 years for the women’s ice hockey team. She recently completed her Masters in Counselling Psychology through City University of Seattle.MacKenzie has worked with children, youth, and their families in a number of settings, through coaching, as a behavioural aid, and counselling through her internship placement. She is excited to continue learning about assessment administration, neurofeedback, and play therapy practices at RMPS! Currently, she is part of the assessment and neurotherapy team, as she completes her final capstone assignment and intends to join our counselling team as a Registered Provisional Psychologist.

Tammy Thomson

Tammy is a graduate of the Master of Arts in Counselling Psychology (MACP) program at Yorkville University and is trained at the master’s level in art therapy as a professional art psychotherapist and member of the Canadian Art Therapy Association. She brings more than 20 years of experience working with children, teens, and families in child development settings, children’s hospitals, and schools as an early childhood educator and elementary teacher.She completed a Bachelor of Applied Science specializing in Child Development Studies at the University of Guelph, Ontario and holds a Graduate Diploma of Teaching and Learning from the University of Canterbury in Christchurch, New Zealand. Tammy is a member of the Canadian Counsellor and Psychotherapy Association and College of Alberta Psychologists while pursuing her next goal of registration as a provisional psychologist. Tammy values a client-centered approach using play therapy and the expressive arts to support those who may find it difficult to articulate their thoughts and feelings with words. Children and families do not need any skill or prior art experience and the art studio is a safe place where children can gain a sense of independence, greater emotional regulation, and confidence through self-exploration. Expressive interventions in art therapy can treat behavioural issues, anxiety, depression, ADHD, autism, learning disabilities, physical and developmental disabilities, and attachment difficulties. As a parent of three young children herself, Tammy understands the complexities of family life using compassion to help parents feel more confident in their role of raising a successful family.

Raquel Freitas

Raquel is an Office Administrator at RMPS. Back in Brazil, her home country, she graduated as a Psychologist and worked as a clinician for the past 5 years. Although she loved working with children and adults, she discovered a new passion: manage the administrative tasks that keep the business running. 

As someone who is passionate about learning new things and developing new skills, with the career transition also came the decision to live abroad and explore a new culture. To serve empathetically and connect with people is Raquel’s main personal and professional goal.

Emma Donnelly

Emma is a Registered Psychologist with the College of Alberta Psychologists. She completed her Bachelor of Arts in Psychology in her hometown at Brandon University, after which she moved to Calgary to earn her Master’s of Science in School and Applied Child Psychology at the University of Calgary.Emma has a passion for working with children and families and has experience doing so in a number of settings, including schools, homes, early intervention programs, and within the community. She specializes in assessment, including psychoeduational, social-emotional-behavioural, and autism assessment. Emma uses a client centred approach to counselling, supported by cognitive behavioural therapy, as well as play-based and attachment-based techniques. She believes in meeting clients where they are at and prides herself in working together with her clients to achieve their goals, improve their functioning, and enjoy their daily life.

Amanda Stoner

Amanda is a Registered Psychologist with the College of Alberta Psychologists. Amanda earned her doctoral degree in Psychology at Brock University in Ontario in 2017, with a specialization in developmental psychology. Amanda provides formal assessment services at RMPS. 

Since 2009, Amanda has received formal training and work experience in private practice settings in conducting psycho-educational assessments for students ranging from preschool through university. Amanda is skilled at test administration, interpretation of data, and report writing for various referral questions including ADHD, Learning Disorders, Autism Spectrum Disorder, Anxiety, Giftedness, and Intellectual Disabilities. Amanda enjoys working with people of all ages from diverse backgrounds, and she tries to make the testing environment feel relaxed and comfortable while maintaining integrity in testing protocol.

Denise Riewe

Denise has completed a Bachelor of Health Sciences through the University of Lethbridge and a Master of Counselling with Athabasca University. She is a Registered Provisional Psychologist with the College of Alberta Psychologists and a member of the Psychological Association of Alberta.Denise has over 9 years of experience supporting children, youth and their families in both residential and community-based practices. Denise is experienced in working with high and at-risk youth, supporting children and their families with strength-based approaches. She practices from a client-center approach supported by Cognitive Behaviour Therapy, Dialectical Behaviour Therapy, Theraplay, and other play and art-based modalities.

John Pynn

John is a Registered Provisional Psychologist with the College of Alberta Psychologists. He completed his Master of Arts in Counselling Psychology at Yorkville University. He brings more than 20 years of experience working with children, teens, and families in a variety of settings. He brings a relaxed and collaborative atmosphere to sessions.John uses an integrated counselling approach including client-centred, Cognitive Behavioural Therapy (CBT), and Solution-Focussed therapy (SFT) to find the best-fit for clients. He has experience with a variety of mental health concerns including anxiety, depression, anger, self-
esteem, relationships, parenting, ADHD, grief/loss, addictions, and trauma. This broad experience comes from working in schools, social service agencies, group-care, and clinical settings. He also draws from the practical experience of being a parent to two teenagers as well as a husband. Supporting and empowering clients with mental health concerns is something John genuinely enjoys. John also provides counselling for adults and holds a Gottman level 1 certification for couples therapy.

Zara Crasto

Zara is a Psychometrist/Psychological Assistant at RMPS. She completed her Bachelor of Science in Psychology at the University of Calgary and her Graduate Diploma in Psychological Assessment at Concordia University of Edmonton. 

Zara has spent over five years working alongside children, adolescents, and their families in a variety of settings. These include public and private schools, in-home support, residential programs, early-intervention programs, and non-profit organizations. Currently, Zara is part of the assessment and neurotherapy team. As a lifelong learner, Zara plans to go back to graduate school and eventually become a psychologist one day.

Kellie Lanktree

Kellie is a Registered Psychologist with the College of Alberta Psychologists. She completed a Bachelor of Child and Youth Care with the University of Victoria and a Master of Education in Counselling Psychology through the University of Lethbridge.Kellie has over 10 years experience supporting children and youth with developmental disorders/delays and their families. Kellie has experience working in schools, clinical settings, and within homes to provide support and therapeutic interventions. Through her time at RMPS, Kellie has also gained experience in helping individuals affected by trauma, grief/loss, separations, emotional dysregulation, depression, and anxiety. Kellie practices through developmental, attachment-based and trauma-informed lenses, and draws from a variety of play-based approaches such as Synergetic Play Therapy, Child-centered play therapy, DIR/Floortime, art-based mediums, and mindfulness-based practices. Kellie also provides Neurofeedback therapy, and is working on receiving her certification through BCIA. Kellie believes in meeting children and their families where they are at and that there is no “one size fits all” for therapy.