September 30, 2025

Why Do So Many Young People Miss an ADHD Diagnosis? Insights from a New Study

Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most common neurodevelopmental conditions, yet many young people, especially girls, receive a diagnosis late or not at all. This matters, because a delayed diagnosis often means missed opportunities for support, treatment, and improved long-term outcomes. A recent study by Barclay and colleagues (2024) sheds new light on why ADHD recognition is inconsistent, and what we can do about it.

The Study:

Researchers analyzed data from nearly 10,000 children in the UK Millennium Cohort Study. They compared children whose ADHD was recognized early (ages 5–7), later (ages 11–14), or not recognized at all, despite evidence of symptoms. The team also looked at differences between boys and girls to better understand why diagnosis patterns vary by sex.

Key Findings:
  1. Severity Drives Earlier Recognition
    Children who were diagnosed at a younger age often had more visible difficulties: emotional outbursts, peer conflict, conduct issues, and lower cognitive scores. In other words, the “louder” and more disruptive the symptoms, the more likely ADHD was flagged early.

  2. “Quieter” ADHD May Be Overlooked
    Children with stronger prosocial skills or higher cognitive ability were less likely to be recognized, even if they had clear ADHD symptoms. These children may be able to “mask” their difficulties, or adults may misinterpret their struggles as personality quirks rather than signs of ADHD.

  3. Emotional Dysregulation Matters
    Emotional dysregulation—big swings in mood, difficulty calming down, intense frustration—was strongly linked to recognized ADHD in boys, but not in girls. This suggests that clinicians may pay closer attention to these behaviors in boys, while overlooking them in girls.

  4. Co-occurring Conditions Can Influence Diagnosis
    Children with autism were more likely to have their ADHD identified. On the flip side, those who engaged in more physical activity were slightly less likely to be recognized, though the reasons for this are not yet clear.

What This Means for Clinicians:

The study highlights the importance of looking beyond the “classic” hyperactive child stereotype when considering ADHD. Clinicians should:

  • Pay attention to symptoms of emotional dysregulation, even if they are not part of standard diagnostic checklists.

  • Consider ADHD in children with good grades or strong social skills if other symptoms are present.

  • Be mindful of gender differences, since girls may be more likely to internalize symptoms or present with inattentiveness rather than hyperactivity.

What This Means for Parents and Patients:

If you’re a parent, it’s important to trust your observations. If your child struggles with focus, organization, or emotional regulation—even if they are doing well academically or socially—these could still be signs of ADHD. Advocating for an evaluation can make a big difference.

Moving Forward

This study makes clear that ADHD is not one-size-fits-all. Recognition often depends on how symptoms show up, how disruptive they appear, and even the child’s gender. By broadening our awareness and refining our screening practices, we can ensure that fewer children slip through the cracks and more receive the support they need early in life.

Barclay I, Sayal K, Ford T, John A, Taylor MJ, Thapar A, Langley K, Martin J. Investigating the reasons behind a later or missed diagnosis of attention-deficit/hyperactivity disorder in young people: A population cohort study. JCPP Adv. 2024 Dec 18;5(3):e12301. doi: 10.1002/jcv2.12301. PMID: 40979729; PMCID: PMC12446718.

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What We Know About ADHD in Female Populations

A new consensus statement updates what is known about ADHD in girls and women, and offers professional advice

Boys are three times as likely as girls to be diagnosed with ADHD, and anywhere from three to sixteen times more likely to be referred for treatment.

An international team of experts recently published a consensus statement addressing this discrepancy and offering guidance to rectify the imbalance and improve diagnosis and care for girls and women with ADHD. Here are some key conclusions.

ADHD symptoms:

-Experts caution that ADHD behaviors typically express themselves differently in boys than in girls.
-That in turn leads to gender-based biases in teachers and parents. In two studies in which teachers were shown vignettes of individuals with typical ADHD behaviors, switching from female to male names and pronouns led to higher rates of referral for support and treatment.

Comorbidity:

-A major reason for this different expression of ADHD in boys is that they have much higher rates of comorbid externalizing disorders, such as the conduct disorder and oppositional defiant disorder, leading them to break rules and get into fights in school. This no doubt contributes to lower rates of referral for girls.
-On the other hand, females are more likely to have comorbid internalizing disorders, such as emotional problems, anxiety, and depression. These may be interpreted as primary conditions, and the link to ADHD is missed altogether.
-Because ADHD has come to be associated with many externalizing disorders, it is then easy to fail to identify it when it is associated with internalizing disorders such as eating disorders.
-Untreated ADHD in girls can increase the risk of substance use disorders.

Associated vulnerabilities:

Children with ADHD are more likely to be unpopular with their peers and to experience rejection. Whereas boys are more likely to experience that rejection in physical ways, girls are more likely to experience it in social ways and through cyberbullying. That, in turn, contributes to lower self-esteem, which could explain some comorbid internalizing disorders.

Symptoms of hyperactivity/impulsivity, one of the two key components of ADHD, are associated with higher rates of risk-taking behavior:

- Like males with ADHD, females with ADHD have higher injury rates.
-Both males and females with ADHD are more likely to underachieve in school or drop out altogether.
-Overall, adolescents with ADHD become sexually active earlier, have more sexual partners, and are more frequently treated for sexually transmitted diseases than their normally developing peers. That also leads to higher rates of teenage and unplanned pregnancies.
-As with males with ADHD, females with ADHD have higher rates of criminal behavior than normally developing peers. While females with ADHD are still half as likely to be convicted of a crime than males with ADHD, one study showed they nevertheless are eighteen times more likely to be convicted of a crime than normally developing females.

Compensatory or coping behaviors:

- Girls may turn to drink alcohol, smoking cannabis, smoking cigarettes, or vaping nicotine to cope with emotional anguish, social isolation, and rejection.
-Some girls may seek to build social support through high-risk activities such as joining a gang, becoming promiscuous, and engaging in criminal behavior.

Triggers for possible referral

Ages 5-11:

-Bedwetting, nail-biting

Ages 5-16:

-Early sexualized behavior

Ages 5-18:

-Suspensions, expulsions, frequent detentions
-Poor attendance/truancy
-Consistent lateness, poor organization
-Academic difficulties, low academic self-esteem
-Conduct problems, conflicts with parents and peers
-Bullying (usually as victims)
-Regular tobacco and alcohol use
- Obesity and other eating disorders
- Repeated injuries
- Sleep difficulties
- Executive function difficulties
- Extreme emotional meltdowns

Ages 12 and above:

- Relationship problems, anxiety about relationships
- Social rejection, isolation
- Substance abuse, including alcohol
- Risky sexual behavior
- Underage or unwanted pregnancy
- Delinquency or criminal behavior (including shoplifting, vandalism)
- Low self-esteem
- Self-harm, suicidality

Ages 16 and above:

- Dropping out of school
- Losing jobs
- Parenting problems
- Criminality
- Financial difficulties
- Traffic crashes
- Internalizing conditions: depression, anxiety

Ages 18 and above:

- Gambling problems, compulsive shopping
- Personality disorder
- Chronic fatigue syndrome
- Fibromyalgia

The key message is not to disregard females because they do not present with the externalizing behavioral problems, or the disruptive, hard-to-manage boisterous, or loud behaviors typically associated with males with ADHD.

Diagnosis

The authors emphasize that "comprehensive assessment should be completed to accurately capture the symptoms of ADHD across multiple settings, their persistence over time, and associated functional impairments. High rates of comorbidity are typically present. The assessment process is typically tripartite, involving the use of rating scales, a clinical interview, and ideally objective information from informants or school reports."

Rating scales: Ideally rely on those that provide female norms, making them more sensitive to female presentation.

Clinical interviews:

-Be mindful of age-appropriate, common-occurring conditions in females with ADHD, including autistic spectrum disorder, tics, mood disorders, anxiety, eating disorders, fibromyalgia, and chronic fatigue syndrome.
- Be alert to signs of self-harming behaviors(especially cutting), which peak in adolescence and early adulthood.
-Given that heritability of ADHD is high, ranging between 70-80% in both children and adults, be mindful that informants who are family members may also have ADHD (possibly undiagnosed) which may affect their judgment of "typical" behavior. The assessor should obtain specific examples of behavior from the informant and use these to make clinically informed judgments, rather than relying upon the informants' perception of what is typical or atypical.

Treatment

Pharmacological:

- Recommendations for medication do not differ by sex, except that pharmacological treatment is generally not advised during pregnancy or breastfeeding.
- A systematic review and network meta-analysis recommended methylphenidate for children and adolescents and amphetamines for adults, taking into account both efficacy and safety. Larger confidence intervals about the tolerability and efficacy of bupropion, clonidine, and guanine were reported, indicating less conclusive results about the efficacy and tolerability of these oral medications. The use of medication should be followed up over time to verify if medications are effective and well-tolerated, and to manage the effects of related conditions(e.g. anxiety, depression) if they emerge.

Non-pharmacological:

- Cognitive behavioral therapy (CBT) together with psychoeducation (which can be provided to both patients and parent/guardians together or independently) are the best forms of psychological treatment.
- Parents and other guardians of teenage girls need to be shown how to identify deliberate self-harming or risky behavior.
- Adolescent girls may require assistance in addressing risky behavior (sexual risk, substance misuse) and improving self-management. Girls with ADHD are more vulnerable to sexual exploitation and have higher rates of early and unwanted pregnancy.
- Adults are more likely to require interventions to address employment problems, child-rearing, and parenting. Women with ADHD are also more vulnerable to sexual exploitation, including physical and sexual violence.
- Interventions should support attendance and engagement with education to avoid early school-leaving, diminished educational attainment, and associated vulnerabilities. While externalizing conditions have a greater impact on classroom behavior, internalizing conditions affect motivation and thus the ability to benefit from education.

Institutional outreach

- Educational, social care, occupational, and criminal justice system professionals should be trained to improve the detection and referral of ADHD in girls and women.
- Flexible learning systems and support with childcare can help women with ADHD return to education after having a baby.
- Depending on the country of residence, women who disclose their disability to their employer may be entitled to reasonable adjustments to the workplace to accommodate their condition.
- Low to no-cost apps are available to assist persons with ADHD with itineraries, lists, and reminders.
- Career planning should take into account that some occupations may provide a better fit for women with ADHD: "some individuals with ADHD show a preference for more stimulating environments, active, hands-on, or busy and fast-paced jobs."
- Persons with ADHD, both male and female, make up roughly a quarter of the prison population: "Evidence indicates that ADHD treatment is associated with reduced rates of criminality, is tolerated and effective in prison inmates, and improves their quality of life and cognitive function. This has led to speculation that effective identification and treatment of ADHD may help to reduce re-offending."

The authors concluded, "To facilitate identification, it is important to move away from the previously predominating disruptive boy stereotype of ADHD and understand the more subtle and internalized presentation that predominates in girls and women."

March 1, 2022

Understanding Hyperactivity in Women with ADHD: Absent or Hidden?

ADHD (Attention-Deficit/Hyperactivity Disorder) has often been seen as a condition that mainly affects boys, especially when it comes to hyperactivity. However, a new study challenges this idea by showing that hyperactivity is also common in women with ADHD, pointing out the need for better diagnoses.

The study included 13,179 adults with ADHD and 1,910 adults without it. Researchers measured how active participants were using a special test, looking at both "provoked" activity (activity triggered by specific tasks that puts the brain “online”) and "basal" activity (resting or natural activity levels when the brain is “offline”). The study included almost an equal number of men and women, with the goal of finding out if there were any differences between the sexes in ADHD diagnosis, particularly in hyperactivity.

The results were eye-opening. Although men generally showed higher levels of activity when the brain was online, both men and women with ADHD had much higher levels of both offline and online activity compared to people without ADHD. Specifically, those with ADHD had about twice the resting activity and three times the provoked activity compared to those without the disorder.

A key finding was that women with ADHD had hyperactivity levels similar to men with ADHD. This goes against the common belief that women with ADHD don’t show hyperactivity or show it less. It suggests that hyperactivity in women may be missed or misunderstood due to societal expectations or differences in behavior.

These findings have big implications. They suggest that the way we currently understand ADHD, especially hyperactivity in women, might be wrong. By recognizing that women with ADHD can have significant hyperactivity, doctors can diagnose ADHD more accurately. This could lead to earlier treatment and better management of ADHD in women, which might also lower the chances of related problems like anxiety or depression.

The study highlights the importance of thinking about gender differences when diagnosing and treating ADHD. By realizing that hyperactivity isn't just a "male" trait, we can better support everyone with ADHD and ensure they get the right care. As research on ADHD continues, it’s important to challenge old assumptions and take a more inclusive approach to understanding and treating the disorder.

October 1, 2024

ADHD Affects the Efficacy of Treatment for Eating Disorders in Adult Women

ADHD Affects the Efficacy of Treatment for Eating Disorders in Adult Women

Swedish researchers examined outcomes for adult women who sought treatment at the Stockholm Center for Eating Disorders over two years and nine months. Out of 1,517 women who came to the clinic, 1,143remained eligible for the study, after excluding women whose symptoms did not fulfill the DSM-IV criteria for eating disorders or had incomplete records.

Of these, seven hundred patients could not be reached or declined to participate, leaving 443 for follow-up. To guard against the possibility that the follow-up group might not be representative of the overall treatment group, researchers compared to age, body mass index, and scores on tests for depression, anxiety, compulsively, inattention, and hyperactivity. The only statistically significant differences were small ones. The median age of the group lost to follow-up was one year younger, they were less likely to be living alone, and on average scored a single point higher on the depression test. Otherwise, they were broadly similar.

The one-year follow-up on the study group found a substantial difference in the rate of recovery from eating disorders between those with and without comorbid ADHD. Almost three out of four patients (72%) who scored lower (between 0-17) on the World Health Organization adult ADHD self-report scale had recovered from their eating disorder. Among those scoring18 and higher, on the other hand, it was less than half (47%). This difference was extraordinarily unlikely (one chance in one thousand) to be due to chance(p=.001).

Another way of expressing this is through odds ratios. Those scoring 18 and up on the ADHD self-report scale were about two and a half times less likely to recover from their eating disorders following treatment. More specifically, thy were about three times less likely to recover from the loss of control and binging, and almost three and a half times less likely to recover from purging.

To improve outcomes, the researchers suggest "identifying concomitant ADHD symptoms and customizing treatment interventions based on this." They specifically propose controlled clinical trials to explore the effect of combining stimulant medications with standard treatment for eating disorders

June 10, 2021

Untreated ADHD Nearly Doubles Risk of Motor Vehicle Crashes

Untreated ADHD nearly doubles risk of motor vehicle crashes, new meta-analysis finds

The Background:

Motor vehicle crashes remain one of the most significant public health challenges in the United States. In 2022 alone, nearly 44,000 people died on American roads, and more than 2.6 million crash-related injuries required emergency care. Most people are familiar with the usual suspects: drunk driving, speeding, and distracted driving from phones. These risks are well-documented and the focus of ongoing public safety campaigns. 

But a serious risk factor has been flying under the radar: untreated ADHD. Despite receiving little attention from the public, policymakers, or transportation safety agencies, it may belong in the same conversation as these better-known dangers. 

ADHD is not currently recognized by the National Highway Traffic Safety Administration as a driving risk factor; yet inattention and impulsivity, two of its defining features, are consistently cited as common contributors to crashes. Beyond these core symptoms, adults with ADHD may also experience emotional dysregulation, which can further impair driving behavior. 

The Research:

Prior studies on ADHD and crash risk have produced estimates ranging from a 5% to a 70% increase. This massive heterogeneity has made it difficult to draw firm conclusions. This new meta-analysis set out to offer some clarity on these numbers. 

Researchers focused specifically on adults aged 18 to 65 with a formal ADHD diagnosis who were not receiving treatment, comparing them to controls without ADHD. Four studies met these criteria, collectively covering more than 2.75 million people. 

The Results:

The findings were striking: untreated ADHD was associated with a 93% increase in crash risk (95% confidence interval: 88%–99%). There was no evidence of publication bias. Although there was meaningful variation across studies, most of it stemmed from the smallest study  (just 36 participants)  which reported an outlier estimate of a 16-fold increase. 

To put the 93% figure in context: a separate meta-analysis found that alcohol use is associated with a 150% increase in crash risk. Another way to understand just how significant this risk really is, untreated ADHD raises crash risk by more than half as much as alcohol does.

The analysis also found a dose-response relationship between ADHD symptom severity and crash risk: each incremental increase in symptom severity corresponded to a 5–6% higher crash risk. At the highest severity levels, crash risk approached that associated with alcohol use. This gradient reinforces that we're not looking at a binary distinction between “has ADHD” and “doesn’t” — the worse the symptoms, the greater the danger on the road. 

The Takeaway:

These findings have practical implications for patients, families, clinicians, and policymakers alike. Untreated ADHD is not a minor footnote in the driving safety literature; rather, it is a substantial, measurable, and potentially modifiable risk factor. The question of whether and how it should be factored into licensing policy, clinical practice, and public health messaging deserves serious attention. 

August 28, 2026

Childhood Exposure to Noise and Air Pollution and ADHD: A Meta-analysis

As populations grow, more children are growing up surrounded by traffic noise and polluted air.   In most cities, these two factors tend to go hand-in-hand; yet, most previous research has examined these exposures separately. Many reviews focused on a single pollutant (such as fine particulate matter, PM2.5), or on a single developmental window, such as pregnancy or early childhood. Few have asked how noise and air pollution compare as risk factors, or how prenatal and postnatal exposures differ in their effects. 

A new meta-analysis set out to address those gaps. It examined evidence on both environmental noise and several major air pollutants in relation to ADHD, compared exposures before versus after birth, and pooled data across countries and regions. Eligible studies involved children and adolescents under 18, used objective measures of environmental exposure, and assessed ADHD using either clinical diagnosis or standardized rating scales. 

Noise 

Nine studies, combining data from over 100,000 children and adolescents  (all in European countries and Canada) found that high noise exposure was associated with 3% greater odds of ADHD. Prenatal noise exposure showed no effect; childhood exposure alone drove the association, at 4% greater odds. This is a negligible effect size that could easily reflect unmeasured confounding factors rather than a true causal relationship. 

Nitrogen dioxide 

Thirteen studies covering nearly one million children and adolescents in Europe, Canada, China, and South Korea found that nitrogen dioxide (NO₂) exposure was associated with 11% greater odds of ADHD. As with noise, prenatal exposure showed no independent effect. When the analysis was restricted to the five studies that used clinical diagnoses alone — generally considered the most reliable measure — the estimated odds rose to between 20% and 80% higher. The wide range reflects substantial variation across studies. 

Pollutants with no significant effect 

Four studies (97,500 participants) examining nitric oxide (NO), three studies (over 63,000 participants) on ozone, and three studies (over 28,000 participants) on sulfur dioxide found no significant associations with ADHD. 

Particulate matter 

The strongest associations emerged for particulate matter. Twelve studies involving nearly 160,000 participants in China, the US, Canada, and Europe found that exposure to fine particles (PM2.5, 2.5 microns in diameter) was associated with 30% greater odds of ADHD. Ten studies covering more than a quarter of a million participants in India, China, South Korea, and Europe found that coarser particles (PM10, 10 microns) were associated with 50% greater odds. In both cases, prenatal exposure showed no association, which is consistent with the fact that fetuses do not breathe air through developed lungs. When restricted to clinically diagnosed ADHD, PM2.5 was associated with roughly 50% greater odds, and PM10 with more than double the odds. 

The Results

Across all exposures examined, particulate matter showed the clearest and strongest associations with ADHD, followed by nitrogen dioxide. Noise reached statistical significance but at a trivially small effect size. Nitric oxide, ozone, and sulfur dioxide showed no significant associations. 

The authors found no evidence of publication bias which strengthens confidence in the overall pattern. However, there was marked heterogeneity across individual studies: results varied considerably, which urges caution in treating any single estimate as definitive. These are associations, not proven causal relationships, and the possibility that unmeasured factors explain part of the signal cannot be ruled out.

New Expert Guidance on "Deprescribing" Stimulants for Adults with ADHD

The Background: 

Over the past two decades, diagnostic rates for adult ADHD have roughly doubled, and stimulant prescriptions in the United States skyrocketed by more than 50% between 2012 and 2023, particularly among girls and women. While these medications help many individuals manage their symptoms, a landmark 2026 article published in European Neuropsychopharmacology tackles an important question that is rarely discussed: When should doctors and patients consider stopping them?  

The Discussion: 

To answer this, the American Society of Clinical Psychopharmacology (ASCP) gathered a task force of 45 international experts spanning 12 countries. Through a rigorous evaluation process, they reached an overwhelming agreement on a framework for "deprescribing", the planned, supervised reduction or cessation of a medication. Here are the core insights from these ground-breaking guidelines and what they mean for adults navigating long-term ADHD treatment.  

When the Treatment Isn’t Yielding Benefits 

One of the most straightforward reasons to consider stopping a stimulant is if it simply isn’t doing its job. The task force agreed that if a patient does not experience an optimal response, measured by actual symptom reduction, improved daily functioning, and a better quality of life, even after trying a high, optimized dose, it may be time to step back and look at alternative options.  

Sometimes, the issue goes back to the initial evaluation. The criteria for diagnosing ADHD have expanded over the years, and brief psychiatric evaluations can occasionally lead to diagnostic inaccuracies. If a thorough reevaluation reveals that the original ADHD diagnosis was incorrect, the expert consensus is clear: stimulant deprescribing is appropriate unless another stimulant-responsive condition is evident. Furthermore, if a patient develops a persistent tolerance to the drug that cannot be resolved by safe dose adjustments, a temporary taper or drug holiday may be recommended.  

When the Risks to Health Outweigh the Rewards 

Our bodies and health needs naturally shift over time, meaning a medication that worked safely years ago might pose a threat to your health today. The experts concluded that deprescribing should be heavily considered if stimulants exacerbate a concurrent medical or psychiatric illness. For example, although rare, stimulants can unintentionally trigger mania or psychosis in adults with unstable or unrecognized comorbid bipolar disorder.  

Physical health developments are equally critical. If an adult develops a newly arising or unstable cardiovascular condition, such as a cardiac arrhythmia, ischemia, or cardiomyopathy, the risk-benefit balance changes dramatically. Additionally, if severe side effects occur that cannot be managed by reducing the dosage, or if dangerous new drug-drug interactions emerge, stopping the medication under medical supervision protects the patient's long-term well-being.  

Addressing Misuse and the Complex Role of Cannabis 

Because stimulant medications target brain reward and wakefulness circuitry, they can foster a propensity for misuse. Studies indicate that more than 1 in 5 adults prescribed stimulants have misused them, and 1 in 6 have diverted their medication to others. The task force emphasizes that deprescribing is warranted if a patient persistently takes doses higher than prescribed against medical advice, uses the medication purely for unauthorized performance enhancement, or has an untreated, coexisting substance use disorder.  

And what about cannabis? This topic sparked the most debate among the experts, falling just short of an official consensus with 71% agreement that regular cannabis use alone shouldn't automatically trigger a stimulant stoppage. Recognizing the complexity, such as how chronic cannabis use can overlap with ADHD executive function deficits, the task force proposed a structured monitoring approach instead of an immediate cutoff. Clinicians are encouraged to track the patient every 1 to 3 months using standardized symptom tools and random urine drug screens to verify whether cannabis use is actively neutralizing the stimulant's therapeutic benefits.  

The Path Forward: Safe Tapering and Lifestyle Support 

If you and your doctor decide that stopping a stimulant is the right path, it shouldn’t happen overnight. The task force strongly recommends that medications be gradually tapered off at a rate tailored to the individual to minimize potential disruptions and distinguish between transient withdrawal and a true return of ADHD symptoms.  

Crucially, stopping a medication doesn't mean stopping treatment. The experts highlight that the success of any deprescribing plan is significantly enhanced when patients focus on optimizing modifiable lifestyle factors. Prioritizing sleep hygiene, staying physically active, and implementing structured behavioral strategies can support executive functioning and help sustain your cognitive gains even as the medication is reduced or eliminated.  

The Takeaway: 

The decision to continue or stop an ADHD medication is a deeply personal one that requires balancing real-world efficacy, safety, and individual health changes. These new consensus recommendations provide an essential roadmap to help adults navigate their long-term mental health journeys safely and effectively.  

Are you or a loved one currently evaluating your long-term relationship with ADHD medication? Consider scheduling a check-in with your healthcare provider to discuss whether your current treatment plan still perfectly matches your health needs today.