Canstock Images/ADHD(copy).jpgWhat is ADHD?

ADHD (Attention Deficit Hyperactivity Disorder) is one of the most common neuro-behavioural disorders in childhood. Children with ADHD have difficulty with attention, hyperactivity, impulsivity and behavioural problems.

Much of what is written about ADHD is the subject of debate. The wider medical and scientific community generally agrees that ADHD is a condition that can be broken down into three sub-categories:

  • ADHD inattentive type
  • ADHD hyperactive or impulsive type
  • ADHD combined type

Generally an ADHD child will be diagnosed with one of the above three depending on their symptoms.

Inattentive Type

Symptoms of inattentive type ADHD include:

  • Inability to pay attention to details or a tendency to make careless errors in schoolwork or other activities
  • Difficulty with sustained attention in tasks or play activities
  • Apparent listening problems
  • Difficulty following instructions
  • Problems with organisation
  • Avoidance or dislike of tasks that require mental effort
  • Tendency to lose things like toys, notebooks, or homework
  • Easily distracted
  • Forgetfulness in daily activities
  • Hyperactive or Impulsive Type

Hyperactive or impulsive type

Symptoms of hyperactive or impulsive type ADHD include:

  • Fidgeting or squirming
  • Difficulty remaining seated
  • Excessive running or climbing
  • Difficulty playing quietly
  • Always seeming to be "on the go"
  • Excessive talking
  • Blurting out answers before hearing the full question
  • Difficulty waiting for a turn or in line
  • Problems with interrupting or intruding

Combined Type

Combined type ADHD involves a combination of the other two types and is the most common.


Nobody knows the exact number of children with ADHD in New Zealand. According to the American Psychiatric Association, 9% of U.S. adolescents have ADHD and the average age of diagnosis is 7 years old.

For reasons unknown, ADHD is 3 to 4 times more likely to occur in males than females.

Onset & duration

The onset of symptoms is early in childhood, before 7 years of age (generally noticeable at 4-5 years). These symptoms continue into adulthood for approximately 75% of ADHD sufferers, although levels of hyperactivity may decrease with age.


While most experts agree that the condition is primarily biological in nature, there is no agreement as to cause.

Researchers have suggested that genetics may be responsible for some cases of ADHD, but non-genetic factors (such as exposure to toxins or episodes of oxygen deprivation) have also been identified as possible causal factors.


Co-morbidity refers to the child having additional problems as well as ADHD. Up to 66% of children diagnosed with ADHD have additional problems. 30-50% will have conduct disorder (CD), and 20-25% will have anxiety issues.

Generally, 20-30% of ADHD children also have learning problems and up to 30% have delayed motor development.


Currently, a diagnosis depends on a complete evaluation. To be considered for a diagnosis of ADHD:

  • A child must display behaviours from one of the three subtypes before age 7
  • These behaviours must be more severe than in other kids the same age
  • The behaviours must last for at least 6 months
  • The behaviours must occur in and negatively affect at least two areas of a child's life (such as school, home, daycare settings, or friendships)
  • The behaviours must also not only be linked to stress at home. Children who have experienced a divorce, a move, an illness, a change in school, or other significant life event may suddenly begin to act out or become forgetful. To avoid a misdiagnosis, it's important to consider whether these factors played a role in the onset of symptoms.