Fewer than half of ADHD assessments in Australia follow recommended diagnostic guidelines, raising concerns about the reliability of diagnoses for young people.

A recent study published in the Australian Psychologist journal found guideline adherence in just 48.6 per cent of cases, while only 31.6 per cent of psychologists correctly identified all ADHD diagnostic criteria.

ADHD affects an estimated six to 10 per cent of children and up to 6 per cent of adults in Australia, with assessments typically conducted by psychologists, psychiatrists, or paediatricians.

Despite this, only 45 per cent of clinicians reported using Australia’s official ADHD guidelines.

According to the article, inconsistent assessment practices can lead to misdiagnosis, delayed treatment and negative outcomes including poor academic performance, mental health issues and social difficulties.

Dominic Baickdeli, who has a severe ADHD diagnosis, says the process of getting diagnosed felt unclear and rushed.

“The first part of my diagnosis involved a survey where I felt pressured to over exaggerate my answers, and once I met up with the psychologist, it felt rushed and didn’t feel very professional,” he says.

Before his diagnosis, Mr Baickdeli says he struggled with concentration and felt “behind” in class, but after receiving treatment he was able to focus and improve academically.

However, he raised concerns about how ADHD is sometimes managed.

“I definitely think that it is overdiagnosed quite a bit. A lot of people I know are on high doses of ADHD meds when it really isn’t necessary,” he says.

Associate Professor of Clinical Psychology at Curtin University Trevor Mazzucchelli says inconsistent practices may stem from a lack of awareness and standardisation across the profession.

“It could be just lack of awareness as to what is warranted for a diagnosis,” he says.

He says proper ADHD assessments should involve multiple sources of information, including interviews, developmental history and evidence of symptoms across different settings, rather than relying on a single report or checklist.

Curtin Research Fellow Dr Louise Brown, an ADHD coach and advocate, says inadequate training and failure to follow guidelines can lead to inaccurate diagnoses.

“If clinicians aren’t properly trained, there’s a risk of missing other conditions or misdiagnosing ADHD altogether”

Dr Louise Brown

She says over-diagnosis can also occur when assessments rely too heavily on self-reported symptoms without ruling out other explanations.

“This can contribute to stigma and misinformation about ADHD, while also exposing people to medications they may not need,” she says.

Curtin Student Guild accessibility officer Mia Antenucci says delays in diagnosis can prevent students from accessing critical support.

“A large issue is getting a formal diagnosis. It can take a long time and be expensive,” she says.

She says a diagnosis is required for accommodations such as extra time in assessments, meaning students who cannot access one are often left without support.

Dr Mazzucchelli says improving education and enforcing clearer guidelines would help ensure more consistent and accurate diagnoses, which aligned with the study’s findings.

“I think guidelines and greater education, would be a big step towards appropriate assessments,” he says.