Neurodevelopmental Disorders: Diagnosis and Clinical Assessment
Core concepts
Diagnosis is clinical and dimensional. Know DSM-5 criteria for autism spectrum disorder (social communication deficits plus restricted/repetitive behaviors, early onset, functional impairment), ADHD (inattention and/or hyperactivity-impulsivity across settings), intellectual disability (deficits in intellectual and adaptive function), specific learning disorder, and communication and motor disorders. Understand the role of standardized instruments (ADI-R, ADOS-2, Vineland, Bayley, WISC) and when to use them. Know the differential: hearing loss, language disorder, social anxiety, reactive attachment, and global delay can mimic autism. Review genetic and metabolic testing pathways, neuroimaging indications, and EEG indications. Understand comorbidity clustering and the importance of multi-informant, multi-setting assessment.
Traps
Questions test cross-setting impairment: ADHD requires symptoms in more than one setting. Do not diagnose autism without early onset and restricted/repetitive behaviors. Avoid overreliance on a single test; diagnosis integrates history, observation, and collateral. Watch for attributing social deficits to autism when hearing or language is the cause.
Rule of thumb
Diagnose by pattern, not single symptom: require the full criterion set, impairment, and developmental appropriateness.
Worked example: A 6-year-old with poor eye contact but no repetitive behaviors and normal language at home and school-consider social anxiety or language disorder before autism.