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

Population Study Links ADHD Medication with Reduced Criminality, Suicides, Automotive Crashes, Substance Abuse

Many studies have shown that ADHD is associated with increased risks of suicidal behavior, substance misuse, injuries, and criminality. As we often discuss in our blogs, treatments for ADHD include medication and non-medication options, such as CBT (Cognitive Behavioral Therapy). While non-drug approaches are often used for young children or mild cases of ADHD, medications – both stimulants and non-stimulants – are common for adolescents and adults. 

Global prescriptions for ADHD drugs have risen significantly in recent years, raising questions about their safety and effectiveness. Randomized controlled trials have demonstrated that medication can help reduce the core symptoms of ADHD. However, research from these trials still offers limited or inconclusive insights into wider and more significant clinical outcomes, such as suicidal behavior and substance use disorder.

An international study team conducted a nationwide population study using the Swedish national registers. Sweden has a single-payer national health insurance system, which covers nearly every resident, enabling such studies. The researchers examined all Swedish residents aged 6 to 64 who received their first ADHD diagnosis between 2007 and 2018. Analyses of criminal behavior and transport accidents focused on a subgroup aged 15 to 64, since individuals in Sweden must be at least 15 years old to be legally accountable for crimes or to drive.

The team controlled for confounding factors, including demographics (age at ADHD diagnosis, calendar year, sex, country of birth, highest education (using parental education for those under 25), psychiatric and physical diagnoses, dispensations of psychotropic drugs, and health care use (outpatient visits and hospital admissions for both psychiatric and non-psychiatric reasons).

Time-varying covariates from the previous month covered diagnoses, medication dispensations, and healthcare use. During the study, ADHD treatments licensed in Sweden included amphetamine, atomoxetine, dexamphetamine, guanfacine, lisdexamphetamine, and methylphenidate.

After accounting for covariates, individuals diagnosed with ADHD who received medication treatment showed better outcomes than those who did not. Specifically:

-Suicidal behaviors dropped by roughly 15% in both first-time and recurrent cases.

-Initial criminal activity decreased by 13%, with repeated offences falling by 25%.

-Substance abuse initiation declined by 15%, while recurring substance abuse was reduced

by 25%.

-First automotive crashes were down 12%, and subsequent crashes fell by 16%.

There was no notable reduction in first-time accidental injuries, and only a marginally significant 4% decrease in repeated injuries.

The team concluded, “Drug treatment for ADHD was associated with beneficial effects in reducing the risks of suicidal behaviours, substance misuse, transport accidents, and criminality, but not accidental injuries when considering first event rate. The risk reductions were more pronounced for recurrent events, with reduced rates for all five outcomes.”

Meta-analysis of Non-invasive Brain Stimulation Finds Limited Evidence of Efficacy

Background: 

Pharmacotherapies, such as methylphenidate, are highly effective for short-term ADHD management, but issues remain with medication tolerability and adherence. Some patients experience unwanted side effects from stimulant medications, leaving them searching for alternative ADHD treatments. Alternative treatments such as cognitive training, behavioral therapies, psychological interventions, neurofeedback, and dietary changes have, so far, shown limited success. Thus, there is a critical need for non-pharmacological options that boost neurocognitive performance and address core ADHD symptoms.

First— What Are NIBS (Non-Invasive Brain Stimulation) Techniques?

Non-invasive brain stimulation (NIBS) techniques, including transcranial direct current stimulation (tDCS), transcranial random noise stimulation (tRNS), transcranial alternating current stimulation (tACS), and repetitive transcranial magnetic stimulation (rTMS) are generating growing attention within the scientific community. 

NIBS techniques are methods that use external stimulation, such as magnets or electrical currents, to affect brain activity without any invasive procedures. In transcranial alternating current stimulation (tACS), for example, small electrodes are placed on the scalp of the patient, and a weak electrical current is administered. 

The theory behind these techniques is that when a direct current is applied between two or more electrodes placed on specific areas of the head, it makes certain neurons more or less likely to fire. This technique has been successfully used to treat conditions like depression and anxiety, and to aid recovery from stroke or brain injury. 

The Study: 

Previous meta-analyses have produced conflicting indications of efficacy. A Chinese research team consisting of sports and rehabilitative medicine professionals has just published a network meta-analysis to explore this further, through direct comparison of five critical outcome domains: inhibitory control, working memory, cognitive flexibility, inattention, hyperactivity and impulsivity.

To be included, randomized controlled trials needed to have participants diagnosed with ADHD, use sham control groups, and assess ADHD symptoms and executive functions – such as inhibitory control, working memory, cognitive flexibility, inattention, hyperactivity, and impulsivity – using standardized tests.

A total of thirty-seven studies encompassing 1,615 participants satisfied the inclusion criteria. It is worth noting, however, that the authors did not specify the number of randomized controlled trials nor the number of participants included in each arm of the network meta-analysis.

Furthermore, the team stated, “We checked for potential small study effects and publication bias by conducting comparison-adjusted funnel plots,” but did not share their findings. They also did not provide information on outcome variation (heterogeneity) among the RCTs.

Results:

Ultimately, none of the interventions produced significant improvements in ADHD symptoms, whether in inattention symptoms or hyperactivity/impulsivity symptoms.  Likewise, none of the interventions produced significant improvements in inhibitory control. Some tDCS interventions enhanced working memory and cognitive flexibility, but details about trial numbers and participants were missing. The team concluded, “none of the NIBS interventions significantly improved inhibitory control compared to sham controls. … In terms of working memory, anodal tDCS over the left DLPFC plus cathodal tDCS over the right DLPFC … and anodal tDCS over the right inferior frontal cortex (rIFC) plus cathodal tDCS over the right supraorbital area ... were associated with significant improvements compared to sham stimulation. For cognitive flexibility, only anodal tDCS over the left DLPFC plus cathodal tDCS over the right supraorbital area demonstrated a statistically significant benefit relative to sham. ... Compared to the sham controls, none of the NIBS interventions significantly improved inattention. ... Compared to the sham controls, none of the NIBS interventions significantly improved hyperactivity and impulsivity.”

How Should We Interpret These Results?

In a word, skeptically.

If one were to read just the study’s abstract, which states, “The dual-tDCS and a-tDCS may be considered among the preferred NIBS interventions for improving cognitive function in ADHD”, it might seem that the takeaway from this study is that this combination of brain stimulation techniques might be a viable treatment option for those with ADHD. Upon closer inspection, however, the results do not suggest that any of these methods significantly improve ADHD symptoms. Additionally, this study suffers from quite a few methodological flaws, so any results should be viewed critically.

October 31, 2025

Meta-analysis of Transcranial Direct Current Stimulation Still Yields Little Sign of Efficacy

Background:

Despite recommendations for combined pharmacological and behavioral treatment in childhood ADHD, caregivers may avoid these options due to concerns about side effects or the stigma that still surrounds stimulant medications. Alternatives like psychosocial interventions and environmental changes are limited by questionable effectiveness for many patients. Increasingly, patients and caregivers are seeking other therapies, such as neuromodulation – particularly transcranial direct current stimulation (tDCS). 

tDCS seeks to enhance neurocognitive function by modulating cognitive control circuits with low-intensity scalp currents. There is also evidence that tDCS can induce neuroplasticity. However, results for ADHD symptom improvement in children and adolescents are inconsistent. 

The Method:

To examine the evidence more rigorously, a Taiwanese research team conducted a systematic search focusing exclusively on randomized controlled trials (RCTs) that tested tDCS in children and adolescents diagnosed with ADHD. They included only studies that used sham-tDCS as a control condition – an essential design feature that prevents participants from knowing whether they received the active treatment, thereby controlling for placebo effects. 

The Results:

Meta-analysis of five studies combining 141 participants found no improvement in ADHD symptoms for tDCS over sham-TDCS. That held true for both the right and left prefrontal cortex. There was no sign of publication bias, nor of variation (heterogeneity) in outcomes among the RCTs.  

Meta-analysis of six studies totaling 171 participants likewise found no improvement in inattention symptoms, hyperactivity symptoms, or impulsivity symptoms for tDCS over sham-TDCS. Again, this held true for both the right and left prefrontal cortex, and there was no sign of either publication bias or heterogeneity. 

Most of the RCTs also performed follow-ups roughly a month after treatment, on the theory that induced neuroplasticity could lead to later improvements. 

Meta-analysis of four RCTs combining 118 participants found no significant improvement in ADHD symptoms for tDCS over sham-TDCS at follow-up. This held true for both the right and left prefrontal cortex, with no sign of either publication bias or heterogeneity. 

Meta-analysis of five studies totaling 148 participants likewise found no improvement in inattention symptoms or hyperactivity symptoms for tDCS over sham-TDCS at follow-up. AS before, this was true for both the right and left prefrontal cortex, with no sign of either publication bias or heterogeneity. 

The only positive results came from meta-analysis of the same five studies, which reported a medium effect size improvement in impulsivity symptoms at follow-up. Closer examination showed no improvement from stimulation of the right prefrontal cortex, but a large effect size improvement from stimulation of the left prefrontal cortex

Interpretation: 

It is important to note that the one positive result was from three RCTs combining only 90 children and adolescents, a small sample size. Moreover, when only one of sixteen combinations yields a positive outcome, that begins to look like p-hacking for a positive result. 

In research, scientists use something called a “p-value” to determine if their findings are real or just due to chance. A p-value below 0.05 (or 5%) is considered “statistically significant,” meaning there's less than a 5% chance the result happened by pure luck. 

When testing twenty outcomes by this standard, one would expect one to test positive by chance even if there is no underlying association. In this case, one in 16 comes awfully close to that. 

To be sure, the research team straightforwardly reported all sixteen outcomes, but offered an arguably over-positive spin in their conclusion: “Our study only showed tDCS-associated impulsivity improvement in children/adolescents with ADHD during follow-ups and anode placement on the left PFC. ... our findings based on a limited number of available trials warrant further verification from large-scale clinical investigations.” 

October 24, 2025