Attention Deficit Hyperactivity Disorder (ADHD) is the most common neurodevelopmental disorder, manifesting in symptoms of inattention, hyperactivity or impulsivity. It is a disorder which begins in childhood, and may persist into adulthood if undiagnosed or untreated. ADHD often goes undiagnosed, as symptoms of inattention are not as easily identified. An accurate and reliable diagnosis of ADHD is also crucial, so that patients are not misdiagnosed. This article entails the diagnostic procedures of ADHD and answers the questions of how ADHD can be diagnosed, what are the tests for ADHD and who can test for ADHD.

What is an ADHD Test?

Testing for Attention Deficit Hyperactivity Disorder (ADHD) involves the diagnostic assessment process carried out by experienced professionals, using the appropriate diagnostic tools and guidelines, to provide an opinion on whether their patient has ADHD. The end product of this procedure is a diagnosis of ADHD. Each diagnosis is specific to each patient, as the patient’s background and life context are also taken into account during the assessment process.

The Importance of an Accurate Diagnosis

While ADHD is a highly prevalent disorder, it is also highly misunderstood. This is evident through the high rates of misdiagnosis or undiagnosed ADHD. For example, studies have found that there is a tendency for ADHD to be over-assessed in younger boys and under-assessed in older girls. If ADHD goes untreated due to such inaccuracies in diagnosis, there can be substantial negative repercussions towards a person’s life, affecting their ability to carry out daily tasks, their mental wellbeing and the relationships with the people around them. Thus, it is important that the diagnostic procedures of ADHD are appropriately applied and adhered to by experienced mental health professionals, in order to produce a valid and reliable diagnosis.

Who is qualified to perform testing for ADHD?

ADHD testing

Typically, a test assessing for ADHD would involve a number of professionals who have been trained to carry out the necessary assessment procedures that strictly adhere to the guidelines provided by the fifth and latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). These professionals may include a general physician (GP), pediatrician, psychologist and psychiatrist.

A GP or pediatrician (for children), is able to perform ADHD assessments through the use of diagnostic scales that check for symptoms of ADHD, an evaluation of full medical history and performing medical examinations such as blood tests or ECGs.

A psychologist would also be able to conduct a test for ADHD through diagnostic scales and an overall evaluation of their mental state and life background.

Psychiatrists, when testing for ADHD, administer several psychometric scales, similar or identical to those psychologists do. This is usually required by the local regulations.

How about an ADHD diagnosis test?

Most people who are seeking ADHD testing and diagnostic confirmation, count on both medications and psychological treatment/coaching. It is strongly advisable to check the regulations for ADHD testing and diagnosis in the respective country, to make the ADHD testing process time- and cost-efficient.

For example, in most countries a diagnosis of ADHD made by a psychologist or a neuropsychologist is not sufficient, to access treatment with medications, however the person may be able to access psychological treatments already.

In Australia general practitioners can make a provisional (tentative) diagnosis of ADHD and initiate certain ADHD medications on their own, without an input from a psychiatrist. A formal ADHD testing and a diagnosis from a psychiatrist will be still required, to access a full range of treatment.

In some European countries, e.g. UK, France, Germany, and Australia the diagnosis must be made by a psychiatrist, in order to access medications and other supports, e.g. financial allowance via certain programs. Family doctor and psychologist can then take over the treatment and continue on with the recommendations from a psychiatrist.

In the United States ADHD can be tested and confirmed by a GP/family doctor as well as by a psychiatrist, and the treatment is initiated by the same doctor who made the diagnosis.

How to test for ADHD

Upon referral from an experienced medical and/or mental health professional, a psychiatrist would also perform an ADHD assessment through the use of psychometric scales and an interview-based evaluation of their patient’s mental health history, medical history, background and life context. All the information provided through the scales and the interview is comprehensively evaluated according to the DSM-V guidelines for diagnosing ADHD. Finally, the psychiatrist would form an opinion and produce an official formulation and diagnosis for the patient.

H3 – Testing ADHD in Children
Because of the developmental nature of ADHD, young children may be initially screened for ADHD by their teachers in school, or by their caregivers at home. This may involve simple observations of certain symptoms of inattention, hyperactivity and impulsivity within a child. Such observations may include: difficulties with focusing, daydreaming, poor academic progress or uncooperative behaviour.
When conducting assessments with a licensed professional, a child’s parents, teachers and caregivers may also be interviewed or asked to complete a behaviour rating scale on their child.

Testing ADHD in Adults

With adults, testing and diagnosing ADHD can be more difficult as symptoms of ADHD tend to present in more complex ways as compared to childhood. Oftentimes, adults initially screen themselves for ADHD through online self questionnaires, which lead them to seek an official diagnosis for ADHD. Other times, adults may seek a diagnosis for ADHD after their own child has been diagnosed with ADHD.

When conducting assessments with a licensed professional, the adult may be asked to complete a self-report scale as a checklist for any ADHD symptoms. Furthermore, the adult’s parents, or people who may have known them as a child, may be interviewed or asked to fill out a behaviour rating scale for a more comprehensive evaluation.

Diagnostic Criteria for ADHD

ADHD can be diagnosed through a comprehensive evaluation based on the guidelines provided by the fifth and latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). The DSM-V states that a diagnosis of ADHD would require the presentation of frequent and persistent symptoms of inattention and/or hyperactivity-impulsivity that negatively disrupts a person’s capacity to function and develop normally within their lives.

Mainly, there are 3 types of ADHD symptom presentations.
The Inattentive type presents with symptoms involving difficulties in paying attention, but is not hyperactive or impulsive.

Inattentive symptoms of ADHD include:

  • Inability to focus or sustaining attention
  • Easily distracted by unrelated stimuli
  • Difficulty with organising and completing tasks
  • Avoidance of tedious tasks that require sustained attentional effort
  • Disorganised
  • Often losing belongings
  • Daydreaming
  • ForgetfulnessPoor time management

The Hyperactive/Impulsive type presents with symptoms involving hyperactive and impulsive behaviour, but does not struggle with attentiveness.

Hyperactive-Impulsive symptoms of ADHD include:

  • Inability to sit or stand still
  • Often fidgeting or squirming in their seat
  • Talking excessively or loudly
  • Interrupting others in conversation
  • Intruding on others (lack of boundaries)
  • Impatience

The Combined type involves a combination of both inattentive and hyperactive/impulsive presentations of ADHD symptoms.

The DSM-V’s diagnostic criteria for ADHD

To be diagnosed with ADHD, the DSM-V states that 6 or more of inattention symptoms, and/or 6 or more of hyperactive-impulsive symptoms must be present for a duration of at least 6 months before an ADHD diagnosis can be formulated.

Symptoms must occur across at least 2 or more settings (e.g, at home, school, work, etc.) and must have been present before the age of 12 years.

It is also important that these symptoms cannot be better explained by any other mental disorder, and that they do not occur exclusively during a psychotic episode or psychotic disorders like schizophrenia.

What are the Different Types of ADHD Tests?

Besides thoroughly assessing a patient’s background, life circumstances and presenting symptoms, clinicians may also use diagnostic tools or scales to assist their evaluation.

The most commonly used diagnostic tools include:

  • Behavior Assessment System for Children (BASC), which seeks to assess the emotions and behaviour of young children.
  • Adult ADHD Self-Report Scale (ASRS-v1.1), which is a self-report checklist of all the ADHD symptoms listed in the DSM-V.
  • Diagnostic Interview for ADHD in adults (DIVA-5), which is a self-report checklist of the main core symptoms of ADHD – attention and hyperactivity-impulsivity.

Here is a list of other common scales that may be used:

  • Neuropsychiatric EEG-Based Assessment Aid (NEBA) System, a scan that measures theta and beta brain waves; people with ADHD have higher theta and beta brain waves compared to people without ADHD.
  • Conners Rating Scale, which identifies and evaluates children’s social, behavioural and academic issues.
  • Child Behaviour Checklist/Teacher Report Form (CBCL), an assessment used by educators to identify problematic emotional and behavioural conduct in children
  • Tests of Variable Attention (TOVA) is a computerised test designed to test attentional skills.

ADHD Severity

With testing and diagnosing ADHD, it is important to consider the varying levels of severity in which ADHD symptoms can present and manifest. This is crucial as the severity of ADHD can change and fluctuate across the lifespan, depending on when the diagnosis was made.

According to the DSM-V, there are 3 levels of severity:

  1. Mild: There are a few symptoms present that are sufficient for diagnosis, and the symptoms cause only a minor impairment in their lives.
  2. Moderate: The symptoms and impairments that lie in between “mild” and “severe” ADHD are present.
  3. Severe: There are many symptoms present that are beyond sufficient for diagnosis, and the symptoms cause significant impairments in their lives.


What are common ADHD symptoms in adults?

Common symptoms of ADHD in adults include difficulties in paying attention to details, concentrating for long period of time, disorganisation, prioritisation, starting and completing tasks that require sustained effort, impulsiveness and emotional regulation.

Is ADHD a mental illness?

Technically, yes. Mental illness, or mental disorder, is defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) as a clinically significant disturbance in an individual’s cognition, emotion regulation, or behavior that reflects a dysfunction in the psychological, biological, or development processes underlying mental functioning. Thus, according to these guidelines, ADHD is classified as a mental disorder.

Is it possible to have a successful life when you have ADHD?

Definitely. Many patients with ADHD learn to cope with their symptoms and go on to live their lives like any other individual, given that they are given the right opportunities and access to the resources they need to seek the adequate treatment and support.

At what age does ADHD peak?

ADHD is a neurodevelopmental disorder, which means that it develops in childhood and can manifest into adulthood if untreated. While the intensity of ADHD symptoms can decrease as the patient goes into adulthood, there is no specific age in which ADHD can peak. Some patients can learn to cope with their ADHD, but other patients can still be struggling with the symptoms of ADHD as adults.

Can ADHD affect memory?

Yes, it can. ADHD affects the executive functions, which are the cognitive processes of the brain that allow for self-regulation and behavioural inhibition. Working memory is one of the executive functions. ADHD can lead to the impairment of working memory, which causes symptoms like forgetfulness, difficulties with following instructions and completing tasks.


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