Sex Differences and Executive Function Profiles in Childhood Attention-Deficit/Hyperactivity Disorder: Evidence from...

Area of Science:

• Neuroscience
• Developmental Psychology
• Child Psychiatry

Background:

• Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder.
• Executive functions (EF) are crucial for cognitive control and behavior regulation.
• Understanding sex differences and heterogeneity in ADHD is vital for tailored interventions.

Purpose of the Study:

• To investigate sex-based differences in executive functions (EF) among children with ADHD.
• To explore the heterogeneity of EF within childhood ADHD using a digital assessment battery.
• To identify distinct EF profiles and their relationship with sex and clinical presentation.

Main Methods:

• A cohort of 208 children (aged 7-12) diagnosed with ADHD was assessed using a standardized digital battery (CNS vital signs).
• Analyses included frequentist and Bayesian approaches, controlling for age and employing false-discovery rate (FDR) correction.
• Executive function heterogeneity was examined using k-means clustering, with results validated by hierarchical clustering.

Main Results:

• Multivariate sex effects were not significant, indicating overall similarity in EF between boys and girls with ADHD.
• Significant sex differences favoring boys were found in Psychomotor Speed and Motor Speed after FDR control.
• Clustering identified three severity-graded EF profiles, demonstrating moderate agreement across methods and independence from sex or DSM-5 presentation.

Conclusions:

• Boys and girls with ADHD share comparable EF architectures, with boys showing slight advantages in specific speed-related domains.
• Executive function heterogeneity in ADHD is characterized by three distinct, severity-based profiles.
• These EF profiles are not associated with sex or specific DSM-5 presentations, supporting a dimensional, performance-based assessment approach.