Dec 01, 2024 20:00:00

Children with high IQs may be diagnosed with ADHD at a later age

Attention Deficit Hyperactivity Disorder (ADHD) is a developmental disorder characterized by hyperactivity, impulsivity, and inattention, and 3-7% of school-age children are diagnosed with ADHD. A study conducted by a Canadian research team found that children with higher IQs were diagnosed with ADHD at a later age.

Sex and intelligence quotient differences in age of diagnosis among youth with attention‐deficit hyperactivity disorder - Hare - 2024 - British Journal of Clinical Psychology - Wiley Online Library
https://bpspsychub.onlinelibrary.wiley.com/doi/10.1111/bjc.12485

Children With High IQs Get ADHD Diagnosed Later, Study Reveals : ScienceAlert
https://www.sciencealert.com/children-with-high-iqs-get-adhd-diagnosed-later-study-reveals

ADHD can have a major impact on a child's learning and development, affecting the way they move, concentrate and control their impulses, so the earlier it is diagnosed, the easier it is to take measures to prevent the behavioural problems and poor academic performance associated with ADHD.

However, previous research suggests that women may be less likely to be diagnosed with ADHD, that people with higher IQs may be diagnosed later, and that factors such as socioeconomic status and ethnicity may influence ADHD diagnoses.

So a research team from the University of Western Ontario and Queen's University collected data from 568 young people aged 4 to 22 who had been diagnosed with ADHD, and analyzed the association between age at diagnosis and a variety of factors, including gender, IQ, and socioeconomic status.

The results showed that the higher the IQ of the subjects, the later the age at which they were diagnosed with ADHD. Additionally, factors such as higher socioeconomic status, having a non-white mother, and having non-behavioral symptoms of ADHD were also associated with a later age at diagnosis.

In the graph below, the vertical axis shows the age at which the subjects were diagnosed with ADHD, and the horizontal axis shows the subjects' IQ. Although there is variation among individuals, overall, it can be seen that the higher the IQ, the later the age at which ADHD is diagnosed. Based on the results of previous research, the research team had suspected that 'the effect of IQ on age at diagnosis may be greater for girls than for boys,' but because the sample size of women in this study was small, no gender differences could be confirmed.

The results suggest that children who are perceived as smart, who are good at hiding their symptoms, or whose mothers are ethnic minorities are more likely to have ADHD than those who are not.

The researchers argued that future studies should include participants who may have overlooked symptoms of ADHD and who have not yet been diagnosed with the condition.