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

Norwegian Nationwide Population Study: Single Umbilical Artery Shows Weak Link to ADHD

Counting umbilical cord vessels is standard in prenatal ultrasounds and confirmed at birth. Single umbilical artery (SUA) occurs in about 1 in 200 cases, with roughly 10% associated with anomalies, including central nervous system defects. Isolated SUA (iSUA) means one artery is missing without other structural issues. 

Research on SUA, especially isolated iSUA, and childhood neurodevelopmental disorders (NDD) is limited and inconclusive. iSUA is linked to preterm birth and small-for-gestational age (SGA), both of which are NDD risk factors.  

This Norwegian nationwide population study aimed to assess NDD risk in children with iSUA at birth, the influence of sex, and how preterm birth and SGA mediate this relationship. 

The nation’s universal single-payer health insurance and comprehensive population registries made it possible to analyze all 858,397 single births occurring from 1999 to 2013, with follow-up continuing through 2019. Among these cases, 3,532 involved iSUA. 

After adjusting for confounders such as parental age, education, and maternal health factors, no overall link was found between iSUA and later ADHD diagnosis. However, females with iSUA had about a 40% higher risk of subsequent ADHD compared to those without iSUA, even after adjustment. 

The authors concluded, “The present study indicates that iSUA is weakly associated with ID [intellectual disability] and ADHD, and these associations are influenced by sex. This association is mediated negligibly through preterm birth and SGA. The associations were not clinically significant, and the absence of associations of iSUA with other NDD is reassuring. This finding can be useful in the counseling of expectant parents of fetuses diagnosed with iSUA.” 

 

Large Cohort Study Reports Association Between Eye Disorders and ADHD

Refractive errors, such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism (distorted vision due to irregular curvature of the eye or lens), are common worldwide. These conditions affect 12%, 5%, and 15% of children, and rise significantly in adults to 26.5%, 31%, and 40%. Additionally, strabismus (misalignment of the eyes) and amblyopia (reduced vision in one eye from uneven image formation, often linked to strabismus) occur globally at rates of 2% and 1.4%, respectively. 

Visual impairment can affect children’s concentration in school, and studies suggest a link between eye disorders and ADHD. 

To investigate this relationship, two researchers – one based in the US and the other in Israel –carried out a nationwide retrospective cohort study using electronic medical records of all insured individuals aged 5 to 30 who were part of Maccabi Health Services, Israel’s second largest health maintenance organization, between 2010 and 2022. 

Of over 1.6 million insured members (2010–2020), inclusion/exclusion criteria and propensity score matching for age and sex were applied, along with a one-year wash-out period between the first eye diagnosis and ADHD diagnosis. In total, 221,707 cases were matched with controls without eye disorders at a 1:2 ratio, resulting in a cohort of 665,121 participants.  

Overall, those with any previous eye diagnosis were 40% more likely to have a subsequent ADHD diagnosis. This was slightly higher for females (45%) than for males (35%). It was also slightly higher for children and adolescents (42%) than for adults (37%).  

More specifically: 

  • Myopia (425,000+ participants): 30% higher ADHD rate. 
  • Hyperopia (120,000+) and astigmatism (175,000+): over 50% higher ADHD rate. 
  • Strabismus (13,000+): over 60% higher ADHD rate. 
  • Amblyopia (14,000+): 40% higher ADHD rate. 

The authors concluded that eye disorders are associated with ADHD. They noted these associations were more marked in females and children and adolescents, although, as noted above, those differences were small. They recommended that primary care providers and neurologists consider risk stratification for early screening, and that ophthalmologists refer high-risk patients for ADHD evaluation. 

 

 

February 10, 2026

South Korean Nationwide Population Study: Prenatal Exposure to Acid-suppressive Medications Not Linked to Subsequent ADHD

Acid-suppressive medications, including proton pump inhibitors (PPIs) and histamine-2 (H2) receptor antagonists, are often prescribed during pregnancy to treat heartburn and gastroesophageal reflux disease. 

Research shows changes in the gut microbiome can negatively affect neurodevelopment. Since acid-suppressive medications alter gut microbiota, maternal use during pregnancy may impact offspring’s neurodevelopment. Because PPIs and H2 receptor antagonists readily cross the placental barrier, they could potentially influence fetal neurodevelopment.  

The link between prenatal exposure to acid-suppressive medications and major neuropsychiatric disorders is not well understood. With the use of these medications during pregnancy rising, it is important to assess their impact on children's long-term neurodevelopment. This study examined whether maternal use of acid-suppressive drugs is associated with increased risk of neuropsychiatric disorders in children, using a large, nationwide birth cohort from South Korea. 

South Korea operates a single-payer health insurance system, providing coverage for over 97% of its citizens. The National Health Insurance Service (NHIS) maintains a comprehensive database with sociodemographic details, medical diagnoses, procedures, prescriptions, health examinations, and vital statistics for all insured individuals. 

A Korean research team analyzed data from over three million mother-child pairs (2010–2017) to assess the risks of prenatal exposure to acid-suppressing medications. They applied propensity scoring to adjust for maternal age, number of children, medical history, and outpatient visits before pregnancy, to minimize confounding factors. That narrowed the cohort to just over 800,000 pairs, with half in the exposed group. 

With these adjustments, prenatal exposure to acid-suppressing medications was associated with 14% greater likelihood of being subsequently diagnosed with ADHD. 

Yet, when 151,737 exposed births were compared to the same number of sibling controls, no association was found between prenatal exposure and subsequent ADHD, which suggests unaccounted familial and genetic factors influenced the preceding results. 

The Take-Away:

Evidence of these medications negatively affecting pregnancies is mixed, mostly observational, and generally reassuring when these medications are used appropriately. Untreated GERD and gastritis, however, have known risks and associations with the development of various cancers. With no evidence of an association with ADHD (or for that matter any other neuropsychiatric disorder), there is no current evidence-based reason for expectant mothers to discontinue use of acid-suppressing medications.  

February 6, 2026