We are sometimes asked, “What is the ADHD diagnosis based on? The Diagnostic and Statistical Manual of Mental Disorders (DSM for short) is the manual for the diagnosis and statistics of mental disorders that serves as the standard for psychiatric diagnosis in most countries. The DSM was necessary to end the international confusion in literature about psychiatric disorders. Terms like depression, psychosis or ADHD were interpreted differently by different authors and were often also nationally determined. The DSM brought more unity in the diagnoses. It was necessary to describe all symptoms clearly, to define precisely which symptoms can occur in a clinical picture and how many of the symptoms must be present before one can speak of a certain clinical picture in a patient. ADHD has been described in the following way:

DSM-5 criteria ADHD

A. A persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development, as characterized by (1) and/or (2).

(1) Inattentiveness

Six (or more) of the following symptoms have been present for at least six months at an inappropriate level that adversely affects social, school or professional activities and is not developmentally appropriate.

Please note The symptoms are not simply a manifestation of oppositional behaviour, defiance, hostility or an inability to understand tasks or instructions. Adults should have at least five symptoms. The individual:

• Often fails to pay adequate attention to detail or makes careless mistakes in schoolwork, work or other activities
• Often has difficulty sustaining attention in tasks or play. Often does not seem to listen when spoken to directly
• Often fails to follow directions and often fails to complete schoolwork, chores or work obligations (not a result of positional behaviour or inability to understand directions)
• Often has difficulty organising tasks and activities
• Often avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort (such as school or homework)
• Often loses things needed for tasks or activities (e.g. toys, homework, pencils, books or tools)
• Is often easily distracted by external stimuli
• Often forgetful in daily activities

(2) Hyperactivity and impulsiveness

Six (or more) of the following symptoms have been present for at least six months at a level which is inappropriate and adversely affects social, school or professional activities and is not developmentally appropriate.

Please note The symptoms are not simply a manifestation of oppositional behaviour, defiance, hostility or an inability to understand tasks or instructions. Adults should have at least five symptoms. The individual:

• Often moves his/her hands or feet restlessly, or turns in his/her seat
• Often stands up in class or in other situations where one is expected to stay in one’s seat
• Often runs about or climbs on everything in situations in which it is inappropriate (in adolescents or adults this may be limited to subjective feelings of restlessness)
• Has difficulty playing quietly or engaging in leisure activities
• Often “on the go” or “rambling on”
• Often talks incessantly
• Often blurts out answers before questions are even finished
• Often has difficulty waiting his/her turn. Often disrupts the activities of others or intrudes (e.g. intrudes in conversations or games)

B. Some symptoms of hyperactivity-impulsivity or inattention causing limitations were present before the age of 12.

C. Some of the symptoms in this group are present in two or more areas (for example, at school (or work) and at home).

D. There should be clear evidence of significant impairment in social, school or occupational functioning.

E. The symptoms do not occur exclusively in the course of a pervasive developmental disorder, schizophrenia or other psychotic disorder, and are not previously attributable to another mental illness (e.g., mood disorder, anxiety disorder, dissociative disorder or personality disorder).

DSM-5 distinguishes three subtypes of ADHD:

314.01 Combined picture

If, during the past six months, both criteria A1 (inattention) and A2 (hyperactivity-impulsivity) are met.

Partially in remission

If all criteria were initially met but less than all criteria have been met in the last six months and the symptoms continue to cause limitations in social, school or professional functioning.

Current severity

DSM 5 further specifies the current severity:

Mild

Few or no symptoms in excess of those required to achieve the classification are present, and the symptoms result in only mild impairment of social, school or professional functioning.

Moderate

Symptoms or functional limitations between ‘mild’ and ‘severe’ are present.

Severe

Symptoms far in excess of those needed to classify are present, or several very severe symptoms are present, or the symptoms result in marked impairment of social, school or professional functioning.