Subthreshold Autism and ADHD: A Brief Narrative Review for Frontline Clinicians

Area of Science:

• Neuroscience
• Developmental Psychology
• Clinical Pediatrics

Background:

• Epidemiological studies reveal higher prevalence of neurodevelopmental disorders (NDDs) in the general population versus diagnosed clinical cases.
• This indicates many children with NDDs, including autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD), remain undiagnosed.
• The concept of 'subthreshold' conditions acknowledges impairing neurodevelopmental variations not meeting diagnostic criteria.

Purpose of the Study:

• To review literature on subthreshold conditions related to ASD and ADHD.
• To identify practical insights for clinicians managing neurodevelopmental disorders.
• To explore themes including definitions, prevalence, assessment, impairments, classification, management, awareness, and future research.

Main Methods:

• Conducted a narrative review of published literature.
• Searched electronic databases (PMC, PubMed) using keywords: 'Subthreshold', 'subclinical', 'neurodevelopmental', 'childhood', 'ADHD', 'ASD'.

Main Results:

• Identified key themes: definitions, prevalence, assessment tools, lifetime impairments, NDD classification models, management strategies, public awareness, and research needs.
• Highlighted the spectrum of neurodevelopmental presentations beyond formal diagnoses.

Conclusions:

• Proposes recording 'subthreshold conditions' for NDDs not meeting diagnostic criteria when significant, persistent impairment is evident.
• Emphasizes the clinical relevance of identifying and acknowledging these conditions in children and youth.