#BMJPediatricsOpen

A landmark international study finds younger pupils in a class, often born later in the year, face higher odds of mental health concerns than their older peers. Analyzing health records of more than a million children, the research prompts education systems worldwide, including Thailand, to reconsider strict entry cutoffs that can unintentionally disadvantage students.

Researchers from Norway’s NTNU reviewed health data for children aged 4–17 born between 1991 and 2012. The study shows October–December births—the youngest in many classrooms—have higher rates of ADHD and related neuropsychiatric conditions compared with January–March births. The magnitude of risk varies with prematurity, with ADHD diagnoses among the youngest students rising by about 20–80 percent. A lead neonatology consultant notes a meaningful relative age effect in childhood mental health.

A major new study from Norway has found that children born later in the school year—those who are the youngest in their class—are significantly more likely to be diagnosed with mental health problems than their older classmates. The research, which analyzed data from over one million children, has ignited global debate over how education systems, including Thailand’s, may inadvertently disadvantage their youngest students through rigid school entry cut-off dates. Experts are now urging policymakers and educators to reconsider age-based class placements and provide additional support to mitigate these long-term mental health risks.