The study took advantage of a mobile school-based mental health screening program run by the university’s medical unit in 2022. Rather than recruiting families into a clinic, the researchers brought the assessment to the classroom, relying on teacher-completed ratings on the Thai version of the Swanson, Nolan, and Pelham Version IV scale, widely known as the SNAP-IV. This instrument, originally developed to measure ADHD symptoms against diagnostic criteria, asks teachers to rate how frequently a child displays behaviors such as failing to finish tasks, being easily distracted, fidgeting, interrupting others, arguing with adults, or deliberately annoying peers. Because teachers observe children over many hours in structured settings, their ratings are considered a valuable and practical proxy for identifying children whose behavior falls into the clinically significant range.

The retrospective chart review covered 540 primary school students who participated in the screening program. The headline result was unexpected in its proportions. Clinically significant symptom levels were most prevalent for oppositional and defiant behavior, affecting 38 percent of the children screened, with a 95 percent confidence interval of 34 to 42 percent. Hyperactivity and impulsivity came next, at 15 percent, and inattention was identified in 8 percent of students. For context, global prevalence estimates for diagnosed ADHD in children typically hover around 5 to 8 percent, and ODD estimates generally fall between 2 and 10 percent, although teacher-rated symptom screening tends to capture broader groups than formal clinical diagnosis. Even allowing for that methodological difference, the sheer weight of oppositional symptoms in this sample stands out.

Geography proved to be one of the most powerful variables in the dataset. When the researchers broke the results down by province, they found that prevalence varied significantly across geographic areas, and one province in particular, Nan, in northern Thailand near the border, recorded the highest proportions across every symptom domain. In Nan, clinically significant inattention was observed in 16.8 percent of students, hyperactivity and impulsivity in 23.5 percent, and oppositional or defiant behavior in a remarkable 71.4 percent of screened children. All of these geographic differences were statistically significant, with P values below 0.001, meaning the probability that such variation arose by chance alone is extremely small. The pattern suggests that children in certain border communities carry a substantially elevated behavioral symptom burden compared with their peers elsewhere in the screening catchment.

The study also examined how symptom prevalence and severity differed by sex and grade level, and here the picture became more nuanced. Sex-related and grade-related differences in the distribution of symptom severity varied across the different symptom domains rather than following a single uniform pattern. This is consistent with a well-established body of child psychiatry research showing that boys are more often flagged for hyperactivity and externalizing behaviors, while inattention can present more quietly and be missed in classroom settings, and that the expression of ADHD symptoms tends to evolve as children move through primary school. The authors note that these demographic patterns in symptom-severity distributions differed across domains, underscoring that a single screening threshold applied uniformly may not capture every child who needs help.

Methodologically, the team used chi-square tests and Fisher’s exact tests to compare proportions across provinces, sexes, and grade levels, standard statistical tools for categorical data of this kind. The screening instrument itself has a long pedigree. The SNAP-IV scale was built around the symptom lists of the Diagnostic and Statistical Manual of Mental Disorders, tracing its structure from the DSM-III through the DSM-IV, the DSM-IV Text Revision, and into the DSM-5 era, and it remains one of the most widely used teacher and parent rating scales in ADHD research worldwide. The Thai version used here allows locally validated cutoffs to be applied to teacher ratings, converting everyday classroom observations into standardized scores that flag clinically significant symptom levels. The researchers followed STROBE reporting guidelines for observational studies, and the work received ethical approval from the Institutional Review Board of Srinakharinwirot University, with written informed consent obtained from parents or legal guardians and all data anonymized before analysis.

Why might oppositional and defiant symptoms be so elevated in these border regions? The study itself is descriptive and does not test causal explanations, but the broader literature on child mental health in marginalized settings offers plausible context. Border and remote rural communities in Thailand often face compounded adversity: poverty, limited educational resources, family separation due to labor migration, reduced access to health services, and in some areas the stresses associated with ethnic minority status and cross-border instability. Chronic environmental stress in childhood is strongly associated with externalizing behaviors, and where developmental screening and early intervention are scarce, behavioral difficulties can accumulate unrecognized for years. A teacher in a resource-strained classroom may also rate disruptive behavior more severely when support systems are thin, although the study design cannot disentangle such reporting effects from true differences in symptom burden.

The practical significance of the work lies in what it reveals about service gaps rather than in diagnosis itself. A screening program of this kind does not assign clinical diagnoses; it identifies children whose symptom scores cross thresholds that warrant fuller evaluation. In urban Thai settings, a child flagged by teacher ratings might be referred to a child psychiatrist within weeks. In a border province, the nearest specialist may be many hours away, and families may lack the resources to travel. The authors frame their findings as descriptive epidemiological evidence intended to inform future research, school-based screening programs, referral pathways, and service planning for the early identification and support of children with behavioral difficulties. In other words, the numbers are meant to give health planners a map of where the need is concentrated so that limited specialist capacity can be deployed where it will matter most.

The mobile medical unit model at the heart of the study deserves attention in its own right. By embedding screening within routine school visits, the program reached children who would almost certainly never appear in a clinic-based study, which is precisely the population that most epidemiological datasets miss. This is a recurring problem in global child mental health research: prevalence figures are disproportionately drawn from urban, clinic-adjacent populations, while children in remote and low-resource settings remain statistically invisible. The 540 students in this sample represent a small but meaningful corrective, and the authors are explicit that unequal access to child mental health screening and early intervention remains a major public health challenge in geographically marginalized settings.

There are, of course, limits to what a single retrospective screening review can establish. The data come from teacher ratings at one point in time in 2022, without the multi-informant assessment, clinical interview, and functional impairment evaluation that formal diagnosis requires. The sample, while valuable, is not a nationally representative survey, and the very high oppositional symptom figure in Nan province invites further investigation into local conditions, rating practices, and referral history before firm conclusions are drawn. Still, the study’s core contribution is difficult to dispute: it documents, with standardized instruments and clear statistics, that clinically significant behavioral symptoms are common among primary school children in Thailand’s border regions, that they cluster unevenly across geography, and that school-based screening is a feasible vehicle for finding them. As health systems worldwide grapple with post-pandemic rises in child behavioral and emotional problems, this Thai border-region dataset is a reminder that the children most in need of early identification often live farthest from the clinics designed to provide it.

Subject of Research: Prevalence of ADHD and oppositional defiant disorder symptoms among primary school students in Thailand's border regions

Article Title: Prevalence of clinically significant attention-deficit/hyperactivity disorder and oppositional defiant disorder symptoms and their behavioral characteristics among primary school students in Thailand’s border regions: evidence from a school-based screening program

Article References: Eiamudomkan, M., Khuancharee, K., Narkwichean, A., Muangnoi, P., Charoenthamruksa, C., Wannaiampikul, S., & Tanunyutthawongse, C. (2026). Prevalence of clinically significant attention-deficit/hyperactivity disorder and oppositional defiant disorder symptoms and their behavioral characteristics among primary school students in Thailand’s border regions: evidence from a school-based screening program. BMC Psychiatry. https://doi.org/10.1186/s12888-026-08724-4

Image Credits: AI Generated

DOI: 10.1186/s12888-026-08724-4

Keywords: ADHD, oppositional defiant disorder, school-based screening, child mental health, Thailand, border regions, SNAP-IV, pediatrics, psychiatry, health disparities, teacher ratings, epidemiology

Attention-deficit/hyperactivity disorder, commonly abbreviated as ADHD, is characterized by persistent patterns of inattention, hyperactivity, and impulsivity that interfere with functioning at school and at home. While stimulant and non-stimulant medications remain the best-established treatments, many parents and clinicians are eager for non-pharmacological alternatives, whether because of side effects, incomplete medication response, or family preference. Computerized cognitive training has emerged as one of the most heavily marketed options in this space, promising to strengthen the underlying attentional and executive systems through repeated, game-like practice. The scientific evidence, however, has been inconsistent, with some trials reporting gains on trained tasks and symptom scales and others finding little more than placebo-like effects.

The intervention tested in the new trial, known as IBT-AC01, is a multicomponent cognitive training program developed with input from medical advisors, including some of the study’s authors, and technical support from Infinite Brain Technologies. Rather than targeting a single skill such as working memory, the program combines multiple training tasks aimed at different executive functions, the family of cognitive control processes that includes sustained attention, inhibitory control, and cognitive flexibility. The rationale is that ADHD is a heterogeneous condition and that a broader training battery might engage a wider network of neural systems than single-task programs, which have often shown benefits that fail to generalize beyond the exercises themselves.

To test the program fairly, the researchers conducted a double-blind, parallel-group randomized controlled trial involving 105 children aged 6 to 12 years who had been diagnosed with ADHD. Participants were randomly assigned in equal numbers to receive either the IBT-AC01 training or a control condition. Children in the training arm completed daily sessions lasting 25 minutes, five days a week, for a total of four weeks, a dosing schedule designed to deliver an intensive but manageable course of practice. The trial was registered with the Chinese Clinical Trial Registry under number ChiCTR2200057306 before recruitment, and it was approved by the Ethics Committee of Shenzhen Children’s Hospital in accordance with the Declaration of Helsinki, with written informed consent obtained from all parents or guardians and from the children themselves when they were eight years old or older.

The investigators chose two primary outcomes to capture both laboratory-measured cognition and real-world clinical symptoms. The first was the Attention Comparison Score on the Test of Variables of Attention, or TOVA, a computerized continuous performance test widely used to quantify sustained attention and impulsivity. The second was the total score on the ADHD Rating Scale-IV, a clinician- and parent-oriented instrument that tallies the severity of the eighteen diagnostic symptoms of ADHD. Statistical models adjusted for baseline scores, age, and sex were used to compare the two groups, and the analysis followed an intention-to-treat approach, meaning that every randomized participant was analyzed according to their original assignment regardless of adherence, a conservative strategy that preserves the randomization and reduces bias.

The headline result was sobering for proponents of cognitive training. In the primary analysis, there were no statistically significant differences between the training group and the control group on either primary outcome. For the TOVA Attention Comparison Score, the adjusted between-group difference was a modest 0.33 points, with a 95 percent confidence interval spanning from minus 0.54 to 1.20 and a p-value of 0.45, well short of conventional significance thresholds. For the ADHD Rating Scale-IV total score, the adjusted difference was minus 1.07 points, with a confidence interval from minus 3.73 to 1.59 and a p-value of 0.43. In plain terms, after four weeks of intensive daily training, the children who completed the multicomponent program could not be distinguished from controls on either objective attention testing or rated symptom severity.

Yet the trial did not stop at the overall null result. In a methodologically interesting twist, the team applied an exploratory technique called model-based recursive partitioning, a form of statistical decision-tree analysis that searches a data set for subgroups of participants who respond differently to treatment. Rather than pre-selecting candidate subgroups based on theory alone, this approach lets the data reveal where treatment effects may diverge. The analysis flagged three characteristics associated with potentially greater benefit from IBT-AC01: younger age, the presence of comorbid oppositional defiant disorder, and higher baseline ADHD symptom severity. Children with more severe starting symptoms and those whose ADHD was complicated by defiant and oppositional behavior appeared, in this exploratory analysis, to derive more advantage from the training than the sample as a whole.

These subgroup findings come with important caveats that the authors themselves emphasize. Exploratory analyses of this kind are hypothesis-generating rather than confirmatory; because the subgroups were identified after the fact within a modest sample of 105 children, the signals could reflect statistical noise, and the confidence in any single partition is limited. Still, the patterns are biologically and clinically plausible. Younger children may have more malleable attentional systems and greater room for developmental gains, while children with more severe baseline symptoms have more distance to travel, leaving more scope for measurable improvement. The link with comorbid oppositional defiant disorder is intriguing and suggests that cognitive training might interact with the broader behavioral profile of a child in ways that uniform group averages conceal.

The trial’s design strengths deserve attention in a field where commercial cognitive-training products have often been evaluated with weak methodology. The double-blind structure, active control condition, registered protocol, intention-to-treat analysis, and adjustment for baseline covariates all reduce the risk of inflated effects. At the same time, the study raises questions about dosing and duration: four weeks of training, while intensive, may simply be too short to produce durable changes in the neural circuits supporting attention, or the gains may be too narrow to register on generalized outcome measures. Prior research on cognitive training has repeatedly documented the gap between improvement on trained tasks and transfer to everyday functioning, a phenomenon sometimes called the transfer problem, and the present results are consistent with that literature.

For families and clinicians, the practical message is one of tempered expectations. Multicomponent computerized cognitive training, at least in the form and dose tested here, cannot currently be recommended as a stand-alone treatment for ADHD in children, and the overall evidence base continues to suggest that its effects, when present, are modest and uneven. The exploratory subgroup results, however, offer a constructive direction for future research: larger trials designed from the outset to test whether younger children, those with comorbid behavioral difficulties, or those with severe symptoms respond preferentially could clarify who, if anyone, benefits most. The authors call for studies with larger samples to confirm efficacy and to probe the mechanisms underlying any differential response. Until then, the trial stands as a reminder that in cognitive intervention research, the average effect can hide as much as it reveals, and that careful, registered, randomized evidence remains the only reliable compass for navigating a crowded and commercially appealing treatment landscape.

Subject of Research: Efficacy of multicomponent computerized cognitive training for children with ADHD in a randomized controlled trial

Article Title: Efficacy of multiple-component cognitive training for ADHD children: a randomized controlled trial with subgroup analysis

Article References: Wu, Y., Xu, L., Cao, X., Wu, Z., Wang, Y., Xue, G., & Yang, B. (2026). Efficacy of multiple-component cognitive training for ADHD children: a randomized controlled trial with subgroup analysis. BMC Psychiatry. https://doi.org/10.1186/s12888-026-08683-w

Image Credits: AI Generated

DOI: 10.1186/s12888-026-08683-w

Keywords: ADHD, cognitive training, randomized controlled trial, children, executive function, TOVA, ADHD Rating Scale-IV, oppositional defiant disorder, non-pharmacological intervention, subgroup analysis, BMC Psychiatry, Shenzhen Children's Hospital

Montelukast, sold originally under the brand name Singulair, works differently from inhaled steroids. Rather than calming airway inflammation directly, it blocks leukotriene receptors, molecules involved in the inflammatory cascade that narrows airways during asthma attacks. Because it comes as a once-daily pill rather than an inhaler, it is far easier to give to young children, and adherence rates reflect that convenience. In prescription claims data, the median proportion of days covered among children who filled at least one prescription was 52 percent for montelukast but only 27 percent for ICS. That practical advantage has made the drug an increasingly popular second-line controller worldwide, though prescribing patterns vary dramatically: in the United States roughly 10.5 to 16.5 percent of children with asthma use montelukast, while in South Korea the figure reaches 44.8 percent.

The drug’s neuropsychiatric reputation, however, has been contested for years. Spontaneous adverse event reports have linked montelukast to sleep disturbances, hyperactivity, attention problems, depression, anxiety, agitation, aggression, irritability, stuttering, seizures, and even suicidal behavior. The FDA responded in 2020 with a boxed warning about serious mental health side effects. Yet the large observational studies that followed produced contradictory results. A US cohort study by Paljarvi and colleagues found that adding montelukast to ICS treatment raised the incidence of neuropsychiatric events by about a third, while a Swedish study by Wintzell and colleagues, comparing montelukast against long-acting beta-agonists, found no elevated risk at all. The new research was designed specifically to resolve why such studies disagree.

The research team, led by Xue-Feng Jiao and senior author Anick Bérard of CHU Sainte-Justine in Montreal, exploited a methodological advantage that only birth cohorts can offer: complete health records stretching back to each child’s birth. The American cohort, AM-PREGNANT, drew on the MarketScan Commercial Database covering more than 2.5 million children born between 2003 and 2021, while the Quebec Pregnancy Cohort followed children born between 1998 and 2015. From these populations the investigators identified children aged 1 to under 18 whose first-ever asthma diagnosis was followed by either montelukast monotherapy or ICS monotherapy. Crucially, they excluded any child with a pre-existing psychiatric or neurological diagnosis, prior psychotropic medication use, or chronic diseases such as diabetes or congenital heart disease, eliminating confounders that plagued earlier work.

The numbers were striking. In the American cohort, 85,322 asthmatic children were included, with 21,534 starting on montelukast and 63,788 on ICS. The Quebec cohort contributed 11,854 children, of whom 373 received montelukast. The median age at treatment start was around two and a half years in both cohorts, a detail that matters because asthma most often begins before age six, and the neuropsychiatric outcomes examined, including sleep disorders and ADHD, typically emerge in early childhood. Children were followed until a first diagnosis of an outcome, a change in controller medication, discontinuation of treatment, or the end of their insurance enrollment.

When the two cohorts were pooled through random-effects meta-analysis, montelukast initiation was associated with a 40 percent higher risk of ADHD compared with ICS, with a pooled adjusted hazard ratio of 1.40 and a 95 percent confidence interval of 1.19 to 1.66. The risk of oppositional defiant and conduct disorders, conditions marked by defiance, temper tantrums, aggression, and destructiveness, was 43 percent higher, with a hazard ratio of 1.43. By contrast, the analysis found no significant differences between the drugs for mood disorders or anxiety disorders. The median time from starting montelukast to an ADHD diagnosis was 640 days in the American cohort but only 131 days in Quebec, and sleep disorder diagnoses in Quebec appeared a median of just 21 days after the first prescription fill.

Sleep disorders told a more complicated story. The two cohorts disagreed sharply, with substantial statistical heterogeneity between them: Quebec showed a dramatically elevated risk, with a hazard ratio of 5.51, while the American cohort showed essentially no association. The researchers traced the discrepancy to differences in asthma severity. Over 90 percent of Quebec children had controlled or partly controlled asthma, compared with only 44 percent in the American cohort, and only 2 percent of Quebec children used oral corticosteroids during follow-up versus roughly half in the United States. When the team stratified children by asthma control, montelukast was linked to increased sleep disorder risk precisely in the subgroup with controlled or partly controlled asthma, and among children who never needed oral corticosteroids. Severe, poorly controlled asthma itself disrupts sleep, the authors explain, which can mask any additional drug effect.

Seven sensitivity analyses tested the robustness of the findings, and the core results held. The associations persisted when children with any prior montelukast or ICS exposure were excluded, when outcome definitions were broadened to include prescriptions for hypnotic or ADHD medications, when grace periods for medication adherence were redefined, when children with less than 30 days of cumulative treatment were removed, when the asthma definition was loosened, and when propensity score weighting and matching replaced conventional regression. The researchers also applied validated correction factors to adjust the recorded duration of ICS prescriptions, a known weakness of claims data, and used the validated Pharmacoepidemiologic Pediatric Asthma Control Index to account for asthma severity, addressing the confounding-by-indication problem that has undermined previous studies.

Why might a leukotriene receptor antagonist influence the developing brain? The mechanism remains unresolved, but several biological hypotheses exist. Network pharmacology analyses have identified dozens of intersecting molecular targets of montelukast associated with sleep disorders, implicating pathways ranging from receptor activation in chemical carcinogenesis to estrogen signaling. Other proposed mechanisms include interference with the glutathione detoxification system in the brain, dysregulation of neurotransmitter and neurosteroid pathways involving the hypothalamic-pituitary-adrenal axis, and disruption of mitochondrial function in neurons. The overlap between ADHD and disruptive behavior disorders, which co-occur in roughly half of children with ADHD, suggests that montelukast-induced ADHD and montelukast-induced oppositional and conduct disorders may share common underlying mechanisms, consistent with the hostility, irritability, and restlessness already listed in the FDA-approved drug labeling.

The authors caution that their study cannot fully exclude residual confounding, that prescription fills may not equal actual intake, and that the mostly preschool-aged population prevented assessment of later-emerging outcomes such as psychosis or self-harm. Still, the design, capturing children at the very first asthma diagnosis with longitudinal data from birth, offers some of the cleanest evidence yet on this safety question. The practical message for clinicians and families is vigilance rather than alarm: when montelukast is prescribed, parents and physicians should watch for insomnia, dream abnormalities, sleepwalking, inattention, hyperactivity, impulsivity, temper tantrums, defiance, hostility, and aggression, and weigh these risks against the drug’s genuine convenience advantage, particularly for children whose asthma is already well controlled.

Subject of Research: Neuropsychiatric safety of montelukast compared with inhaled corticosteroids in children with newly diagnosed asthma

Article Title: Neuropsychiatric outcomes after montelukast versus inhaled corticosteroids in pediatric asthma: a pooled birth cohort study

Article References: Jiao, X.-F., Ducharme, F. M., Leal, L. F., Longo, C., Sheehy, O., Kaguelidou, F., & Bérard, A. (2026). Neuropsychiatric outcomes after montelukast versus inhaled corticosteroids in pediatric asthma: a pooled birth cohort study. BMC Medicine, 24(1), Article 536. https://doi.org/10.1186/s12916-026-05235-7

Image Credits: AI Generated

DOI: 10.1186/s12916-026-05235-7

Keywords: montelukast, pediatric asthma, ADHD, sleep disorders, oppositional defiant disorder, conduct disorder, inhaled corticosteroids, drug safety, pharmacoepidemiology, birth cohort, FDA boxed warning, neuropsychiatric adverse events