How is ADHD diagnosed?

What to do if you suspect ADHD

There is no single test for ADHD. If you think you or a loved one may have ADHD, the first thing to do is speak to your doctor. The doctor will ask you about you or your loved one’s symptoms, when the symptoms started, and where they occur (i.e. at home, in school, or at work). It is important to be honest with your doctor, so he or she can determine if the behaviour is part of growing up or if it is symptoms of ADHD.

To get a complete picture of you or your loved one’s condition, your doctor will also need to talk with family members and to teachers or work colleagues if it is necessary. The doctor will probably ask whether there is a family history of ADHD and if you or your loved one has any other health conditions. If the doctor sees that the symptoms are making it difficult to manage daily life, including school, work, or relationships with friends or family, you will likely be referred to an ADHD specialist.

Who makes the final ADHD diagnosis?

The doctor who diagnoses ADHD is someone with specific training and expertise in recognizing and treating the condition—a specialist psychiatrist or paediatrician. Other appropriately qualified healthcare professionals with training and expertise can also make an ADHD diagnosis. Your doctor will most likely recommend a specialist or another doctor who focuses on ADHD care.

How a specialist determines an ADHD diagnosis

ADHD is difficult to diagnose, because everyone may exhibit behaviours similar to the symptoms occasionally. Even people living with ADHD have different symptoms at different intensity levels. That is why doctors need to gather as much information as possible from all aspects of your life and conduct different tests to make a proper diagnosis. These tests also help clinicians identify your individual needs. You should expect the following three assessments:


The doctor will do a clinical examination to find out whether the symptoms you or your loved one are showing could resemble those of ADHD but in fact be caused by another condition. For example, poor academic achievement could lead to a referral where there is an undiagnosed hearing or vision problem.


The doctor will try to find out more about the symptoms by talking with you or your loved one and with the people who know you well, such as parents, teachers, or friends. If you are in school, the doctor may also be interested in looking at your school reports. With adults, doctors may also find information from spouses or adult siblings to be helpful. The interviews also help the doctor get a better idea of a person’s specific needs so a treatment plan can be tailored accordingly.

Rating scales

Rating scales are tools that specialists use to get a better idea of behaviour and psychology. They help decide whether you or your loved one shows symptoms of ADHD. These scales can also help to identify other medical conditions.

What is needed for a formal ADHD diagnosis?

A formal ADHD diagnosis involves multiple steps. After the specialist has finished all the appropriate tests and has had time to thoroughly review them, he or she will see whether you or your loved one meets the criteria of the medical classification systems. Medical classification systems include the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-V) and the International Classification of Diseases, 10th revision (ICD-10).