A proper diagnosis of ADHD is dependent on a lengthy and thorough process that rules out any other possiblities. On this page, we here at ADHD.org.nz, will outline aspects of what should be included in the diagnostic process.

PLEASE NOTE: The diagnostic process we outline on this page is "the ideal". In reality, however, time and resources will prevent your medical specialist from conducting every aspect of what we suggest here. The information on this page has simply been presented to enlighten you as to what to expect.

1. The first step - visiting a specialist
Naturally, the first step is visiting a paediatric specialist or child psychologist with your child.

To find out which clinicians are available in city/region CLICK HERE.

The first visit is a chance for the clinician to meet the parents and the child. This first visit will also involve the "parent interview" part of the diagnostis process. The interview with the parents will involve questions about the child's past. Questions will deal with issues such as:

• age of symptoms onset
• the child's history
• the child's conduct at home and school
• relationship with parents and other family members
• medical history (both the child and extended family)
• psychosocial adversities (such as poverty, parental absence, family conflict,)

Questions to ask the professional who may do the assessment How do you diagnose for ADHD? Which types of tests or measurements do you use? Do you use the DSM-IV? How do you determine whether symptoms exist in at least two settings? How long will the assessment take? Do other professionals assist in the assessment process? What age range do you assess? Are you knowledgeable about special services provided at public schools for children and youth with ADHD? How long have you been doing assessments for ADHD? If you confirm a ADHD diagnosis, would you be willing to write a letter to, or speak with, school officials? What is your work experience in ADHD? What type of written feedback will I receive when the assessment is completed? (If a Clinical Psychologist) Do you work with a specific physician if medication will be involved? How is medication used in your practice? If medication is prescribed, what might be some of the side effects? What other therapy in addition to medication might you suggest? If I don't want to put my child on medication, would you be able to provide us with other possible solutions?

This interview will highlight any possible alternative explanations of the ADHD-like behaviour, or additional problems. The child should be involved in this initial visit. This will give the clinician a chance to meet the child, build a rapport, and view first hand any of the ADHD symptoms.

Be extremely wary of any clinician that diagnoses ADHD following only one visit. As we said above, "a proper diagnosis of ADHD is dependent on a lengthy and thorough process".

2. The diagnostic criteria
Clinician use "diagnostic criteria" when deciding what is wrong with a patient. Diagnostic criteria outline the symptoms of particular disorders, thus allowing independent doctors to make similar diagnostic decisions concerning a particular patient.

The most commonly used diagnostic criteria in New Zealand is from the Diagnostic & Statistical Manual of Mental Disorders (DSM) from the American Psychiatric Association.

An alternative diagnostic criteria that is occasionally used in NZ, but more commonly in Europe is the ICD-10 criteria. This is maintained by the World Health Organization.

3. Rating Scales
During the parent interview process, the parents are usually asked to fill in a "rating scale" of the child's behaviour. A rating scale is simply a list of questions (or behaviours) on paper that require the parent to answer via a range of values.

For example: An example of a rating scale question may be: How often does your child have trouble getting to sleep? o Never/rarely o once a month o once a week o 3 times a week o 5 times a week o Nightly All that is required of you is to tick the appropriate circle.

Commonly used rating scales for ADHD include the Child Behavior Checklist (CBCL). Other rating scales include:

• Conners Teacher/Parents Rating scales (CTRS,CPRS)
• ADD-H Comprehensive teacher rating scale (ACTeRS)
• Child Attention Problems (CAP) Rating scale

5. Observation

Informal observations of the child in their natural settings (home, office, classroom, or playground) can provide important imformation regarding the child's behaviour, parent/teacher management styles and may highlight salient cues that elicit encourage the child to misbehave. While the observation can assist in the diagnostic procedure, it also provides useful imformation for the treatment programme.

6. Tests
While there is no single test for ADHD, there are several tests that can be conducted and the results can be compared with average results. These tests are useful in differentiating between the 3 sub groups of ADHD (combined type, predominantly inattentive type, and predominantly hyperactive or impulsive type).

Many of the tests used in diagnosing ADHD are "Continuous Performance Tests" (CPT). They measure how long the child can maintain their attention and how impulsive the child can be over time.

Here is a list of test (some CPTs) that may be used in diagnosing ADHD:

• The Conners' Continuous Performance Test
• The Stroop test
• The Integrated Visual and Auditory Continuous Performance Test (IVA)
• The Gordon Diagnostic Systems
• Yale Children's Inventory (YCI)
• Attention Battery (includes Continuous Performance Task Progressive Maze Test and Sequential Organization Test (SOT)
• Wechsler Intelligence Scales for Children (WISC-R)
• T.O.V.A - Test of Variables of Attention
• Learning Efficiency Test II (LETT-II)
• Developmental Test of Visual Motor Integration (VIM)
• Wide Range Achievement Test (WRAT-R)

For an example of one of the tests used in the diagonistic process, have a go at our Stroop test

7. Medical Evaluation
Last, but one of the most important aspects of diagnosis, is the medical evaluation. In order to rule out any other possible physical problems that may result in behaviour similar to the symptoms of ADHD, the child should undergo a thorough medical evaluation conducted by a qualified paediatric specialist.

The medical evaluation should include:

• Patient medical history, including:
  • plunket developmental assessments.
  • use of prescribed, over-the-counter, and illicit drugs.
  • detailed accounts of any previous serious physical injuries.
  • detailed accounts of any previous illness.
• The possibility of visual or hearing problems should be ruled out.
• Blood tests should be conducted (to test for such things as levels of lead).
• If clinical evaluations suggest it, then speech and language evaluations may need to be conducted.

The medical evaluation is basically conducted to rule out other disorders that have similar symptoms, such as:

• Thyroid dysfunction
• Fragile X syndrome
• Fetal Alcohol Syndrome (FAS)
• G6PD deficiency
• Phenylketonuria (PKU)

We finish by saying that the diagnostic process should be seen as a team effort, involving anyone that the child spends a lot of time with (parents, extended family members, teachers,...).