Attention deficit hyperactivity disorder (ADHD) generates controversy. Some believe that it does not exist, whereas others see the reluctance of clinicians to diagnose and treat it as denying effective health care to children.1 Epidemiological studies show that 3-5% of children of school age may be classified as having attention deficit hyperactivity disorder.2 No validated diagnostic test exists to confirm the clinical diagnosis.

It is a complex neurodevelopmental constellation of problems rather than a single disorder. The core symptoms are inattention, hyperactivity, and impulsivity. These are also, however, normal behavioural traits present in unaffected children. The extent to which each causes disability varies and should be seen within the context of a child's developmental level. For example, an active 3 year old, impulsive and frequently interrupting of others, differs from a disruptive, unfocused 8 year old who is unable to cope educationally. Yet both may display core symptoms. Also, it is important to establish that symptoms exist …