Key Takeaways: Children with higher cognitive abilities and social skills often face delayed or missed ADHD diagnoses, especially females, indicating potential sex bias in diagnosis. Emotional and behavioral difficulties, emotional dysregulation, lower cognitive ability, and poorer prosocial skills increase the likelihood of earlier ADHD diagnosis. Emotional dysregulation is gaining recognition as a key ADHD symptom, despite not being included in current diagnostic criteria. Undiagnosed ADHD can undermine development, highlighting the need for assessments if symptoms and functional impacts are present, regardless of academic and social abilities.