Irritability as a Mediator Between Sensory Processing Sensitivity, Theory of Mind, and Behavioral Problems in Children and Adolescents with ADHD

Children with Attention Deficit Hyperactivity Disorder (ADHD) frequently exhibit emotional and behavioral dysregulation beyond core symptoms. Sensory processing sensitivity (SPS), Theory of Mind (ToM) difficulties, and irritability are implicated in these challenges, yet their integrated roles remain under-researched. This study examined the associations among these transdiagnostic dimensions and behavioral problems in a clinical ADHD sample. A total of 142 medication-free children and adolescents (aged 7–16 years) with ADHD in Turkiye were evaluated using validated parent- and clinician-report measures, alongside a performance-based ToM task. Hierarchical regression and mediation analyses were conducted, with a stringent Bonferroni correction (p < 0.001) applied to control for family-wise error across multiple comparisons. While initial bivariate analyses explored the roles of SPS and ToM indices, their predictive associations with internalizing and externalizing outcomes did not survive the conservative Bonferroni correction threshold. Instead, irritability emerged as the most robust and dominant independent predictor of both internalizing (beta = 0.36, p < 0.001) and externalizing problems (beta = 0.36, p < 0.001). Consequently, indirect mediation pathways linking sensory or social-cognitive vulnerabilities to behavioral problems via irritability were not statistically supported under this strict alpha level. These findings indicate that irritability acts as a central, transdiagnostic driver of emotional and behavioral dysregulation in pediatric ADHD. While sensory and social-cognitive profiles are clinically relevant, the data overwhelmingly highlight the direct impact of irritability. Interventions prioritizing emotion regulation and irritability are paramount for reducing symptom burden, while future adequately powered studies are needed to detect potentially subtler indirect pathways in the context of stringent statistical corrections.