Until recently, Attention Deficit Hyperactivity Disorder (ADHD) has been considered primarily a childhood disorder, with only a minority of children continuing to have symptoms in adulthood. A surge in adult ADHD diagnoses occurred in recent years after changes to the diagnostic system made it easier to detect ADHD in adults. This increase has been accompanied by a lot of media
interest, with #ADHD trending on TikTok and other social media platforms as well.

Many people may have now encountered messages such as this:

  • Are you someone who can focus on some projects or activities so intensely that you completely lose touch with time?
  • At the same time, are you also a person who keeps forgetting appointments, can’t pay bills on time, is always late, can’t get organized, and can’t concentrate on unexciting projects, despite your best efforts?
  • Have you often wondered why you find “adulting” so difficult?

If you answered yes to these questions, you may have adult ADHD.

As usual, however, the story is more complicated.

How is ADHD diagnosed in adults?

What are the symptoms?

The diagnostic criteria for ADHD are essentially the same for adults and children. The current diagnostic manual lists 9 symptoms of inattention and 9 symptoms of hyperactivity. Children need to report 6 out of the 9 symptoms of either inattention or hyperactivity to receive a diagnosis of ADHD. Adults need to report only 5 out of the 9 symptoms in either group.

An example of an inattention symptom is “Often fails to give close attention to details or makes careless mistakes at school, work, or during other activities (e.g., overlooks or misses details, work is inaccurate”.

An example of a hyperactivity symptom is “Often blurts out an answer before a question has been completed (e.g., completes people’s sentences, can not wait for turn in conversation).” (DSM-5, APA, 2013)

Adults and females of all ages are more likely to have inattention, rather than hyperactivity symptoms.

However, saying ‘yes’ to 5 or more symptoms is not enough for a diagnosis. To have a clear picture, we need to ask further questions.

Do these symptoms interfere with important life functions?

We all become inattentive, unfocused, forgetful, or impatient sometimes. To receive a diagnosis of ADHD, the symptoms need to directly cause serious problems in the person’s life. For example, do these symptoms result in lower achievements at work or in education? Do they increase social and family problems? Could they be responsible for accident proneness, legal difficulties, or substance misuse in the person’s life?

Do the symptoms occur in several different situations?

If a person is hyperactive or inattentive in some situations (e.g., at work) but not in others (e.g. with friends or family), it is possible that the situation itself is responsible for the problem, not the person.

However, people are not always aware of the problems that their symptoms cause. It can be helpful to consult others in different settings (e.g., friends, spouses, co-workers) to find out whether they see any substantial, ongoing signs of inattention or hyperactivity in those settings.

Have the symptoms been present before age 12?

ADHD is a neurodevelopmental disorder. Therefore, it must have already been present in childhood. Because recall of childhood memories tends to be unreliable, it is important to consider family history very carefully and to find informants or school records to confirm that ADHD caused problems in several different settings (school, home, social situations) before age 12.

Is there an alternative explanation for these symptoms?

This question is perhaps the most important, but also the most difficult to answer.

Sometimes apparent symptoms of ADHD are better explained by another psychological condition or disorder. This other condition may have been with you since childhood. For example, anxiety, stress, depression, and adverse childhood experiences (i.e., family discord, mental health or substance use problems in the family, emotional or physical abuse or neglect of a child) can all cause attention and concentration problems, forgetfulness, impatience and impulsivity both in adults and in children. In those cases, a diagnosis of ADHD would not be helpful, and could in fact be harmful.

Only a very careful clinical assessment can disentangle the cause-and-effect relationships among these symptoms and disorders.

In summary

Symptoms need to be understood in the wider context of the person’s life, rather than just being a shopping list of items to be ticked off. Mental health professionals following best practice guidelines take a very thorough family history and, if possible, seek information from family, friends, significant others, and previous written records (with the client’s informed consent, of course). Therefore, establishing a diagnosis of ADHD with some certainty can be a lengthy and difficult process.

If you think that you have symptoms of ADHD

Don’t jump to conclusions. You may want to start with a well-validated screening questionnaire, such as this. Consider if your symptoms have been present since childhood and whether they are possibly better explained by other problems, such as anxiety, depression, stress, or adverse childhood experiences.

If you think that your experiences fit the diagnosis of ADHD, seek a full assessment from a clinical psychologist or a psychiatrist. Ideally, your mental health professional will follow best practice guidelines to make sure that they do not miss a diagnosis of ADHD, but also that they do not diagnose ADHD when the problems stem from alternative causes, such as anxiety, depression, stress, or early trauma.

Because the most effective treatment for ADHD is stimulant medication, we need to exercise extra caution about potential misdiagnoses. The prescription of stimulants for adults who do not in fact have ADHD can have many far-reaching consequences for the person and society.


References and further reading


Dr Marianna Szabo is a Clinical Psychologist, a leading expert in Mindfulness and a Senior Lecturer in Psychology at the University of Sydney.