What a clinician looks for
Adult ADHD is diagnosed through a clinical interview, not a single test. Using the DSM-5-TR criteria, the clinician checks that:
- there are enough symptoms of inattention, hyperactivity and impulsivity, or both: at least five from one list for adults
- several symptoms were present before age 12
- they appear in two or more settings, such as work, study and home
- they clearly interfere with daily life and have lasted at least six months
- another condition does not explain them better
In the UK, NICE guideline NG87 (recommendation 1.3.1) says ADHD should only be diagnosed by a specialist psychiatrist or another appropriately qualified professional, based on a full clinical and psychosocial assessment, a developmental and psychiatric history, observer reports and an assessment of mental state. If you have not taken one yet, the ADHD check gives you a structured record of six questions and four tasks to bring along.
Why the clinician asks other people
Because symptoms must have started in childhood, diagnosing ADHD in adults relies heavily on reports of past behavior. NIMH explains that a provider may ask to talk to people who know you well, such as a partner, family members or friends, and may look at school reports or other childhood records. This is often called collateral history.
You may also be asked to complete interviews, rating scales or symptom checklists, and sometimes cognitive tests. The clinician will ask about mood, sleep and physical health to rule out other explanations. The CDC notes that a medical and psychological exam may be needed to rule out other health problems that can cause similar symptoms or often occur with ADHD, such as anxiety, depression, sleep problems, alcohol or substance misuse, or learning disabilities. ADHD or something else? covers these overlaps.
Getting assessed in the US
The CDC advises that the first step is to talk with a healthcare provider, who may diagnose ADHD themselves or refer you to a mental health provider. In practice that can be a primary care doctor, a psychiatrist, a psychologist or another licensed clinician who works with adults. Check what your insurance covers, and ask whether the assessment includes a full history and information from someone who knew you as a child.
Getting assessed in the UK
In the UK, start with your GP. The NHS explains that the GP will ask about your symptoms and how they affect your life, may consider other conditions that could be causing them, and may refer you for an assessment with a mental health professional who specializes in ADHD. NICE (recommendation 1.2.10) says adults without a childhood diagnosis should be referred when typical symptoms began in childhood, have persisted throughout life, are not explained by another psychiatric diagnosis and cause at least moderate impairment.
Waiting times vary, and the NHS says they can run to several months or years. In England, you may be able to find a clinic with a shorter wait through your GP under the Right to Choose scheme, including a private clinic that provides ADHD services for the NHS. The NHS page on your choices in the NHS explains the scheme. Ask your GP which options apply where you live.
Getting assessed in Spain and Latin America
In Spain, the public route usually starts with your family doctor in primary care, who can refer you to mental health services. How this works, and how long it takes, varies between regions. Private psychiatrists and psychologists also assess adults; before paying, ask who carries out the assessment and what it includes.
Across Latin America, services differ widely between countries and between public and private systems. In general terms, look for a psychiatrist or another clinician with experience of adult ADHD, and ask whether the assessment covers your childhood history, more than one area of life and other possible explanations. Those three elements are what the criteria require wherever you live.
After the assessment
If you are diagnosed with ADHD, the NHS says the specialist will talk to you about what this means and what happens next, including the help and support available. Support depends on your symptoms and how they affect you. The NHS describes lifestyle changes, changes at work or in study (in the UK these are called reasonable adjustments), medicines started and monitored by an ADHD specialist, and talking therapies such as cognitive behavioral therapy. NIMH describes medication and psychotherapy as the most common treatments for adults, often in combination. Not everyone needs or wants medicine.
If the assessment points to something else, that is useful too. Ask what the clinician thinks explains your difficulties and what support fits.
What to bring to the appointment
- a short list of concrete examples from work, study and home, with how often they happen
- anything that shows how you were as a child: school reports, teachers’ comments, or a relative willing to talk to the clinician
- notes on your sleep, mood, alcohol and caffeine, and any medicines you take
- results from questionnaires or tasks you have done, such as an attention profile, presented as one more piece of information
- what you hope to get from the assessment: an explanation, support at work or in study, or treatment options
An assessment can end with a diagnosis of ADHD, another explanation, or both. Any of these is useful if it leads to the right support. To prepare your examples, signs of ADHD in adults describes how the criteria tend to show up day to day, and our guide to the ASRS explains the questionnaire many clinicians use.
General information, not a diagnosis
This guide explains how ADHD is described and assessed. It does not replace an assessment by a qualified clinician, and the sources it cites do not endorse Neuropsych.
References
- American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR). 2022. https://www.psychiatry.org/psychiatrists/practice/dsm
- National Institute for Health and Care Excellence. Attention deficit hyperactivity disorder: diagnosis and management (NICE guideline NG87). Published 2018, updated 2019. https://www.nice.org.uk/guidance/ng87/chapter/recommendations
- National Institute of Mental Health. ADHD in Adults: 4 Things to Know. https://www.nimh.nih.gov/health/publications/adhd-what-you-need-to-know
- Centers for Disease Control and Prevention. ADHD in Adults. https://www.cdc.gov/adhd/about/adhd-in-adults.html
- NHS. ADHD in adults. https://www.nhs.uk/conditions/adhd-adults/
- NHS. Your choices in the NHS. https://www.nhs.uk/using-the-nhs/about-the-nhs/your-choices-in-the-nhs/