Diagnosis of AD/HD is multifaceted and includes behavioural, medical, and educational data gathering. One component of the diagnosis includes an examination of the child's history through comprehensive interviews with parents, teachers, and health care professionals. Interviewing these individuals determines the child's specific behaviour characteristics, when the behaviour began, duration of symptoms, whether the child displays the behaviour in various settings, and coexisting conditions.

Diagnosis should take place as soon as possible with the ideal age being 6,7 and with screening and detection already possible at kindergarten age. However, diagnosis may be undertaken up to any age. The screening and the clinical diagnosis of AD/HD by qualified healthcare professionals is based on a careful and complete review of an individual’s history, overall patterns of behaviour and the symptoms of the disorder using the diagnostic criteria listed in the Diagnostic & Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV TR) and/or the International Classification of Diseases (ICD-10, Chapter V: Mental and Behavioural Disorders).

These careful assessments follow existing protocols and may also include the observations of a child’s parents and teachers. Evaluation of other possible causes of inattentive or hyperactive behaviour, as well as common coexisting conditions and co-morbidities, including learning disabilities, substance abuse, psychiatric disorders, depression, anxiety disorders and oppositional defiance disorder, is also undertaken depending on the behaviour and age of the individual.


The Diagnostic and Statistical Manual of Mental Disorders (DSM) published by the American Psychiatric Association (APA) provides diagnostic criteria for all currently recognized mental health disorders. It was first published in 1952 and has been revised a number of times since then, the most recent revision being in 2000 (DSM-IV TR). This manual is used by diagnosing physicians and researchers in the United States and in varying degrees around the world. A new edition is expected in 2013.


The International Classification of Diseases (ICD-10 – Chapter V: Mental and Behavioural Disorders) was produced by the World Health Organization (WHO) and is another commonly-used guide for diagnosing AD/HD in Europe and other parts of the world.

Although there have been discrepancies between these two manuals in the past, mainly because revisions did not happen at the same time and the coding systems did not correlate completely, this is no longer the case. Great care has been taken during the last revisions to rectify this situation.

Diagnosing physicians, researchers, etc. are recommended, however, to check that the coding systems correspond with one another when using either manual in order to avoid discrepancies.

Who Diagnoses AD/HD?

This varies from country to country; for details on this, please consult the ADHD-Europe Survey: Diagnosis and Treatment of AD/HD in Europe: Differences, Problems and Progress (www.adhdeurope.eu).

In Belgium, diagnosis can only be made by a paediatrician, neurologist or psychiatrist. Although psychologists are often consulted for AD/HD screening, they cannot prescribe AD/HD medication and therefore work closely with a paediatrician, a neurologist or a psychiatrist. It is the prescribing physician who also makes decisions about changes in dosage and type of medication, as well as the management of side-effects for individual patients. When everything is running smoothly, the family doctor can write prescriptions, but parents should schedule regular 3-6-monthly check-ups with the prescribing physician, more often if problems arise.

How is AD/HD diagnosed?

There is no single test to diagnose AD/HD so a comprehensive evaluation is necessary to reach a diagnosis, which usually includes the following:

  • A thorough medical examination and family history.
  • A general physical and a neurological examination.
  • A comprehensive interview with the parents, the child, and the child’s teacher(s).
  • Standardized screening tools for ADHD.
  • Observation of the child.
  • A variety of psychological tests to measure IQ and social and emotional adjustment.

When choosing a physician, it is best to get recommendations from other parents, a therapist, school psychologist or someone who has had experience with the condition either in a personal or professional capacity. Not all physicians have the knowledge and understanding of this complicated condition to be able to identify and properly diagnose it.

A correct diagnostic procedure includes having the child’s teacher(s), parents and/or nanny/carer complete a Questionnaire, which then becomes part of the data from which a diagnosis is ultimately reached.

Correct procedure would also ideally include the diagnosing physician visiting the school to give a talk to the teachers about how AD/HD affects the child and how s/he can best be taught.

At least two appointments with the diagnosing physician are usually necessary during the course of diagnosis. The physician reaches a conclusion after weighing the evidence from the steps mentioned above, the final piece of the puzzle being the completed questionnaires.

AD/HD is an 85% heritable condition so family history plays a big role in the diagnosis; although in a small number of cases, the reason for the AD/HD symptoms is frontal lobe injury either at birth or afterwards; this is very rare.

Promo 1
Promo 1
Promo 1

ADHD Europe asks for better provisions for Teenagers with ADHD who continue to need access to mental health services after they turn 18.
This must be a priority across Europe so please sign the Declaration:

Click here to get this resource in other languages:

Support Us

We are a non-profit organization staffed entirely by volunteers whose aim it is to provide excellent support, resources, workshops and conferences for those affected by AD/HD, Asperger’s Syndrome, Dyslexia and other related comorbid conditions. We are thankful for all donations to help us achieve this.

Support Us arrow

Join Our Mailing List