Half of psychologists assessing for ADHD don’t follow the diagnostic guidelines, new study shows

Attention-deficit hyperactivity disorder (ADHD) is a condition that develops during childhood and affects 6–10% of kids and 2–6% of adults.

People with ADHD have either mainly inattentive symptoms (such as lacking concentration), mainly hyperactive and impulsive symptoms (such as speaking or acting without thinking), or a combination of the two.

Two people with ADHD can have very different symptoms and experiences. So it’s important for clinicians who diagnose the condition to have the right knowledge and expertise.

But our new research found half of psychologists who assess for ADHD don’t follow the diagnostic guidelines or criteria.

This means less-typical presentations of ADHD – such as in women and girls, quiet inattentive adults and high-achieving students – could be overlooked.

How is ADHD diagnosed?

ADHD is currently diagnosed by a psychologist, psychiatrist, or paediatrician. Queensland GPs can also diagnose ADHD, with more states and territories to follow.

ADHD can’t be diagnosed with a blood test or other single measure. It requires the consideration of multiple factors and information sources, along with clinical judgement.

Australia’s evidence-based practice guideline for ADHD, released in 2022, provides a clear standard for assessment and treatment. It recommends ADHD assessments include a full developmental, mental health and medical history.

Medical assessments should be used to rule out other factors which could look like ADHD, such as sensory impairment, thyroid disease, anaemia, or medication side effects.

The clinician must also consider the social, psychological and clinical context of a person’s symptoms. This requires input from more than one setting and person such as a teacher or family member. The assessment shouldn’t rely solely on questionnaires or looking at the person.

The diagnosis of ADHD should be made in line with diagnostic criteria from the Diagnostic and Statistical Manual of Mental Disorders (the DSM 5) or the International Classification of Disease (the ICD). These require impairments that are out of step with the person’s age, that began before they were 12, and that have impacts across multiple settings, such as home and school or work.

In practice, a comprehensive ADHD assessment could include:

• interviews with a person and a family member covering their history and current situation
• review of school reports
• completion of questionnaires to assist in clarifying the diagnosis
• investigation of any medical issues which may be causing ADHD-like symptoms.

Our study

Our recent study used an online questionnaire of 322 Australian psychologists involved in diagnosing and treating ADHD. We wanted to see how they were assessing for it, if that matched the Australian guidelines, and how well they knew the diagnostic criteria.

The study was limited to psychologists due to the low number of responses from psychiatrists and paediatricians, and because there are many more psychologists than other specialists.

The study relies on anonymous self-reported data. This reduced the likelihood that only the most confident people would participate, or that clinicians would be focused on looking good.

But there’s a chance the psychologists might not remember their assessments accurately, or apply as much effort to the questionnaire as they would to a client.

What we found

Three in four psychologists said they always followed guidelines, with more saying they followed them some of the time. But overall, fewer than half reported assessment practices that actually followed the guidelines.

This suggests people seeking an assessment can’t rely on a clinician’s assurance they’re following the guidelines and need to ask specifically what’s involved.

Almost all psychologists used client interviews and gathered a developmental history. However, only three in four completed a mental health assessment. Less than one in three assessed for other illnesses. None reported performing a sensory assessment.

This makes it much more difficult to instead diagnose a different condition or rule out other potential causes for symptoms.

Next, we gave psychologists in the study a list of the ADHD criteria, and another item from the specific learning disorder criteria (difficulties with learning and using academic skills).

While ADHD is associated with lower grades at school, it’s not a requirement for diagnosis. Someone may meet the criteria for ADHD without experiencing difficulties learning. Kids with a specific learning disorder can also have ADHD, and it’s important these learning difficulties are also detected.

But fewer than one in three psychologists surveyed correctly identified all the ADHD criteria and also rejected the non-ADHD item. This means people who do well in school but struggle in other areas of their life might miss out on a diagnosis.

Likewise, four in ten clinicians did not recognise that symptoms needed to be out of step for the person’s age and stage of development for a diagnosis. This could mean people are diagnosed when they don’t actually fit the criteria.

Overall, these inconsistencies mean people whose symptoms overlap with anxiety, depression, trauma, sleep problems, thyroid problems, hearing or vision issues, or learning disorders are at greater risk of being misdiagnosed or missing out on helpful support.

What should I look for if I’m seeking an assessment?

If you’re concerned about ADHD symptoms for yourself or your child, discuss your concerns with your GP and find out what services are available in your area.

The wait times and costs for assessments can vary widely, so compare your options before committing to an assessment.

If you’re interested in exploring medications, you will need to visit a paediatrician, psychiatrist or, in some states and territories, a GP, as psychologists aren’t able to prescribe medications.

To make sure you or your child is being properly assessed, look at the guidelines and ask before booking what’s involved in the assessment.