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Overdiagnosis: ADHD

Overdiagnosis: ADHD

GP Dr David Turner considers whether we are overdiagnosing adults and children with ADHD

The symptoms of ADHD were identified as far back as 1798. Sir Alexander Crichton, a Scottish doctor, noticed some people were easily distracted and unable to focus on their activities in the way others could. 

What is now called ADHD first appeared in 1968 in the DSM-2 – the second edition of the US Diagnostic and Statistical Manual of Mental Disorders. The publication of the DSM-3 in 1980 expanded the definition of ADHD to include adolescents. It was further subdivided into two categories: ADD with hyperactivity and ADD without hyperactivity. In 1987, the subtypes were removed, and the disorder became known as ADHD.

Cases began to climb significantly in the 1990s. This may be partly due to doctors being able to diagnose the condition more readily, as well as to increased awareness of the condition, in part helped by famous individuals going public with their own diagnosis of ADHD.

Statements by celebrities such as Johnny Depp, Emma Watson and Michael Phelps are likely to have reduced the stigma and led to demand among adults and children to be tested for the condition. This may have fuelled the increase in diagnoses and suspected cases we now see.

Actual prevalence
The current UK population prevalence estimate is 5% among 10- to 14-year-olds and 3%-4% among adults.1 This equates to around 2.6 million people in the UK with an ADHD diagnosis. It is more commonly diagnosed in men than women, and women are thought to be better at ‘masking’ the condition.

Common features
The current DSM-5 defines ADHD as showing a pattern of inattention and/or hyperactivity-hyper impulsivity that interferes with functioning or development. The condition has no known cause but does appear to run in families. 

NICE proposes the following criteria for a case of ADHD, based on expert opinion and the DSM-52: Suspect attention deficit hyperactivity disorder (ADHD) if there are at least six (five in adults) inattention symptoms and/or at least six (five in adults) hyperactivity-impulsivity symptoms that have:

  • Started before 12 years of age.
  • Occurred in two or more settings such as at home and school.
  • Been present for at least six months.
  • Clearly interfered with, or reduced the quality of social, academic or occupational functioning.
  • Not occurred exclusively during the course of a psychotic disorder and are not better explained by another disorder, such as oppositional defiant disorder or conduct disorder.

Inattention symptoms include:

  • Failing to give close attention to detail or making careless mistakes in schoolwork, work or other activities.
  • Difficulty in maintaining concentration when performing tasks or play activities.
  • Appearing not to listen to what is being said, as if the mind is elsewhere, without any obvious distraction.
  • Failing to follow through on instructions or finish a task (not because of oppositional behaviour or failure to understand).
  • Difficulty in organising tasks and activities.
  • Reluctance, dislike or avoidance of tasks that require sustained mental effort.
  • Losing items necessary for tasks or activities such as pencils, mobile phones, or wallets.
  • Easy distraction by extraneous stimuli.
  • Forgetfulness with regards to daily activities. 

Hyperactivity-impulsivity symptoms include:

  • Fidgeting, tapping hands or feet, or squirming when seated.
  • Leaving the seat where remaining seated is expected, such as in a classroom.
  • Running about or climbing in situations where inappropriate, or feeling restless. In adolescents or adults this may be limited to a feeling of restlessness.
  • An inability to play or engage in leisure activities quietly.
  • Being ‘on the go’ or acting as if ‘driven by a motor’. Others may experience the person to be restless or difficult to keep up with.
  • Talking excessively.
  • Blurting out an answer before a question has been completed.
  • Difficulty waiting in turn.
  • Interrupting or intruding on others.

Full diagnostic criteria can be found in the DSM-5.3

The symptoms of ADHD are more difficult to define in adults and tend to be subtler than in children. Generally, adults present less with hyperactivity but exhibit inattentiveness, carelessness, a lack of attention to detail, inability to prioritise and non-completion of tasks, forgetfulness and frequently losing things. Behavioural traits can include mood swings with flares of temper, extreme impatience and risk-taking behaviour.

Reasons for overdiagnosis
A misdiagnosis of ADHD can be made when symptoms overlap with other mental health and neurodiversity conditions, such as depression, OCD, bipolar disorder, anxiety and neurodiversity conditions like autism. Restlessness, sleep disturbance, irritability, mood swings and struggling in social situations are common to all these conditions. 

Children may be misdiagnosed with ADHD because of relative immaturity compared with their peers.4 A younger child will not have the same attention span as a child many months older. Ineffective parenting and problems with family dynamic may lead to behavioural problems in children that are misdiagnosed as ADHD. 

Personality disorders, neurodiversity, conduct disorder, abuse and underlying physical illness can all manifest with symptoms that overlap with ADHD. The pressure on teachers, parents and clinicians to arrive at a quick diagnosis may lead to a temptation to diagnose ADHD which has a single effective oral treatment – oral amphetamines.

Overdiagnosis of ADHD in adults, recently highlighted in a BBC Panorama documentary5,   may occur for a number of reasons. The relative ease and subjectivity of self-diagnosis using online tools may be partly to blame. Some adults may ‘prefer’ to attribute their symptoms to ADHD than to conditions such as depression or anxiety. There may also be a temptation to medicalise behavioural traits like getting bored easily or making mistakes when undertaking repetitive tasks. The stimulant medications used to treat ADHD can make many people without ADHD feel better and focus more effectively. At the most basic level, many patients want an explanation and label for their symptoms, and for many ADHD can offer this.

Supporting a patient’s next steps
If a clinician suspects a misdiagnosis of ADHD, they should discuss this with the patient or parent and consider alternative explanations for their symptoms. It is important to explain to patients that a number of medical conditions have overlapping symptoms with ADHD and the diagnosis, unlike most medical diagnoses, is subjective.

Clinicians must remember to discuss possible implications of a diagnosis of ADHD with patients requesting a referral. Patients should understand that the diagnosis would remain on their medical records forever and could have implications for their future. It is important to discuss with patients, particularly parents of children, the possibility that what may be seen as ‘ADHD symptoms’ are just variations of normal behaviour.


  1. Sayal K et al. ADHD in children and young people: prevalence, care pathways, and service provision.Lancet Psychiatry 2018;5,175-186. Link
  2. NICE Clinical Knowledge Summary. When should I suspect ADHD? November 2022. Link
  3. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 5th edition. Arlington, VA., American Psychiatric Association, 2013. Link
  4. Ford-Jones PC. Misdiagnosis of attention deficit hyperactivity disorder: ‘Normal behaviour’ and relative maturity. Paediatrics & Child Health 2015;20, 200–2. Link
  5. BBC TV. PanoramaPrivate ADHD Clinics Exposed. May 2023. Link

Dr David Turner is a GP in Hertfordshire and a Pulse columnist. Read his blogs here


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Please note, only GPs are permitted to add comments to articles

HELEN RYAN 12 October, 2023 11:11 am

This is a helpful article to read. It states that “In fact, very little is known about the effects of nonprescription stimulants on cognitive enhancement outside of the student population, although it is frequently reported in newspaper articles. Thus, the rumored effects of “smart drugs” may be a false promise, as research suggests that stimulants are more effective at correcting deficits than “enhancing performance.”

David Church 12 October, 2023 12:57 pm

I am not sure about the ‘overdiagnosis’ part, so much as ‘overmedicalising’.
5% would suggest 5 in a hundred, or 2 in a class of 35.
About half or more of my junior school class had a number of these ‘symptoms’. As do many, many of the adults I know.
So, here’s a question : Is it the people with ADHD who are ‘abnormal’, or do they actually make up more than half of the population, but many have masked the symptoms, and is it in reality the ‘normal’ people who are abnormally lacking in imaginative thougt processes?
Either way, is it more of an educational/training matter than a medical matter? – especially if it turns out to affect the majority of the school population?

Daryl Mullen 12 October, 2023 1:08 pm

If 5% have it and they all want medication that would be say 5 appointments per year per patient or 350 appointments per year for an average 7000 list practice.
Where is this capacity to come from?

Rogue 1 12 October, 2023 2:45 pm

Its next to impossible to get children diagnosed with ADHD these days (unlike 10yrs ago).
Now its the turn of the parents to get this ‘fashionable’ diagnosis, saying I couldnt concentrate as a child and am easily distracted now. It cant have anything to do with the hours spent on social media like TikTok positively encouraging a short attention and 10 second junkies! Perhaps that should be the diagnosis now ‘short attention span’?

Liam Topham 12 October, 2023 2:50 pm

“A misdiagnosis of ADHD can be made when symptoms overlap with other mental health and neurodiversity conditions, such as depression, OCD, bipolar disorder, anxiety and neurodiversity conditions like autism.”
or when they overlap with the normal, human condition?
“Restlessness, sleep disturbance, irritability, mood swings and struggling in social situations are common to all these conditions”
and common to the normal, human condition?
amphetamines can help anyone with these “symptoms”, at least to begin with
Apart from the enormous cost, there does not seem to be much of a downside, but then that’s how it started with oxycodone

David Banner 12 October, 2023 4:57 pm

– Every single referral to Adult ADHD I have done was initiated by patient request, never from me.
-Every single referral to Adult ADHD I have done has resulted in affirmation of diagnosis, then discharge with request for a (lifelong) prescription for amphetamines after a 15 minute consultation.
-So either we GPs have been ignorantly missing the diagnosis in these mass hordes of Adult ADHD sufferers all these years, or maybe, just maybe, we’re witnessing classic Social Contagion spread by Tik-Tok et al.

Not on your Nelly 12 October, 2023 6:18 pm

This is not reasonable to tackle in a 10 minute consultation. Everyone wants a referral to confirm or “just in case”. Yet to see one single letter state “this paitent does not have ADHD”.

Some Bloke 12 October, 2023 6:34 pm

Had a very urgent booking from 111 today. Apparently a kid likes to fight his siblings, therefore it’s definitely ADHD and must contact local service immediately!

A Non 12 October, 2023 6:52 pm

David Banner ..completely agree.

Sujoy Biswas 13 October, 2023 12:35 am

0-6m Reflux — Omeprazole scripts
6m-2y Lactose intolerance — Lactose free milk scripts
2y-8y Gluten intolerance — Bread on script
8y-16y ADHD — Amphetamines on script
16y – 25y Depression — Amphetamines and SSRI on script
25y – 45y Substance misuse — Amphetamines (who dares stop them) SSRI(Like diamonds they’re forever) And Benzos on script
45 up The various menopauses and prevention — Amphetamines (who dares stop them) SSRI(Like diamonds they’re forever) Benzos Testosterone Oestrogen a spot of Progesterone Statins and If they bag a Bipolar diagnosis some Lithium too.

At least we will never be out of a job

John Graham Munro 13 October, 2023 2:58 pm

No such condition

Some Bloke 13 October, 2023 5:38 pm

lets consider that it is over underdiagnosed, so everyone you have ever seen needs a thorough review and referral. if they are not seen in time for dinner- it is all GP’s fault for under over- referring and over under reviewing.

Gerrit Huisman 14 October, 2023 11:18 am

Over and under diagnosis are both a problem. I have patients whose chaotic lives have been massively transformed (for the better) since their (late) diagnosis and treatment for ADHD.

Slobber Dog 14 October, 2023 4:26 pm

Doctor, I only got a 2-1 at university and I should have got a first.
I must have ADHD and I want treatment on the NHS.

David Rossiter 24 October, 2023 11:32 am

Given that one third of adult male prisoners have undiagnosed ADHD and are imprisoned for crimes stemming from lack of impulse control, we are clearly under-diagnosing it, and letting a substantial proportion of our patients fail preventably. One of the psychiatrists I was friendly with said that if you treat children from around age 12 to 16, then the prefrontal cortex develops near normally and they do not need further treatment. This suggests a robust service to assess children and treat appropriately would later prevent almost a third of imprisonment which would save more money than it costs and leads to more productive citizens.
ADHD has always been dogged by the judgemental and incorrect assumption that it is to do with chaotic parenting which mirrors the “refrigerator mom” stereotype of autism in the early days and simply reflect the undiagnosed parent with the same condition.
As for those who say it does not exist, I would challenge you to try parenting my son for a day and see if you can get him to concentrate for more than 20 seconds because I can’t even with my supposed expertise.

Bettina Schoenberger 8 November, 2023 5:06 am

David Rossiter I agree. It is such a shame that no time is made for these kids and their assessment. Not everyone is so lucky to be born into a conducive environment and drifting out and away from the societal safety net is all too common. I recently changed my view on fibromyalgia whereby I think the overlap with menopause, degenerative symptoms, psych traits and disorders etc leaves only a few genuine cases. I hope your son is being treated. I am and it changed my life. Btw my Dx at 55y came out of the blue, no self-referral, but I wished I’d considered it myself and this much earlier in life. Well, it was not to be back then and the coping strategies and life itself have made me gain its own set of very valuable skills.