There is no single test to diagnose attention-deficit hyperactivity disorder (ADHD). Instead, a comprehensive evaluation is necessary to:
- Reach a diagnosis and rule out other causes for the symptoms of ADHD
- Establish whether coexisting conditions are present
Such an evaluation requires time and effort and should include a clinical assessment of the individual’s academic, social and emotional functioning. In children, a careful history should be taken from parents and teachers. Often both a psychologist and a medical practitioner (usually a psychiatrist or paediatrician) should be involved in the assessment process.
Before reaching a diagnosis, it’s important to rule out the following conditions, which usually manifest with similar symptoms to those of ADHD:
- Emotional difficulties / social and environmental problems.
- Low muscle tone. Some children have to focus so hard on sitting up straight that they fidget more.
- Motor-coordination difficulties. If present, this often leads to problems with task completion and the quality of work presented. It often coexists in children with ADHD.
- Sensory modulation disorders. These children have problems being tactile or are light defensive. The noise-defensive child has difficulty blocking out background noise when having to pay attention.
- Global development delay. Concentration and functioning should be evaluated according to functional, not chronological age.
- Absence epilepsy, which often presents between the ages of 6 and 10 years. These small seizures cause lapses in awareness, sometimes with staring.
- Sleep disorders such as sleep apnoea cause tiredness and may present as attention disorders.
It’s important to realise that some of the above problems can also be present in children with a classical picture of ADHD. Other problems may present with symptoms suggestive of ADHD, and this often leads to a later diagnosis because the interaction with concentration problems isn’t explored. They often coexist.
In order for a diagnosis of ADHD to be made, the following conditions should be met:
- Some symptoms must have appeared by the age of 12.
- At least six symptoms must be present and must have persisted for at least six months.
- Symptoms must occur in at least two different settings (for example, at school and at home).
- The symptoms must cause significant impairment of social and academic functioning.
Reviewed by Prof André Venter, Head: Clinical Department of Paediatrics and Child Health, Faculty of Health Sciences at the University of the Free State. MB ChB, MMed, PhD (Canada), DCH, FCP (Paed) SA. July 2018.