A Roadmap to Clinical Assessment and Evaluation of Autism Spectrum Disorder

Dear Editor,

Diagnosis of autism spectrum disorder (ASD) is on the rise. The prevalence of ASD is circa 1.1%. This might be attributed to broadening of diagnostic criteria, diagnostic substitution, better awareness, true “epidemic,” or perhaps a composite thereof. Different specialties typically see those children. Herein outlined is a roadmap to the diagnostic assessment of ASD – a hands-on for busy clinicians.

A primary step is to deploy a developmental screener, e.g., Bricker and Squires Ages and Stages Questionnaire. This should be followed by an autism-specific screener in the presence of red flags [Table 1], e.g., Robin's Modified Checklist for Autism in toddlers (18–36 Mon) or Rutter's Social Communication Questionnaire (older than 4 years). If the score is within the risk range, a comprehensive assessment is warranted.

Table 1.

Red flags in Autism Spectrum Disorder

Diagnostic tools of ASD for clinical and research purposes include “gold standard” Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule-2^nd Edition. Alternatives include, e.g., Krug's Autism Behavior Checklist, Schopler's Childhood Autism Rating Scale, and Wing's Diagnostic Interview for Social and Communication Disorders.

Assessment of core domains should normally ensue once ASD diagnosis is clinically entertained. This would entail, e.g., Bishop's Child Communication Checklist, Constantino's Social Responsiveness Scale, and Bodfish Repetitive Behavior Scale-Revised. It sounds also intuitive to screen sibs for possible ASD as risk recurrence rates are 10-18% (boys at 3-fold more risk).[1]

Cognitive assessment then follows for prognostication and typically includes Intelligence Quotient (IQ)or developmental quotient with a pattern of lower verbal and preserved performance scores. For those under 6, Mullen Scales of Early Learning might be of use. Nearly 38% are associated with ID (more in females and hence severe phenotype) and hence poor prognosis.[2]

Speech/language assessment should be undertaken for both receptive and expressive abilities (e.g., Dunn's Peabody Picture Vocabulary Test) as well as pragmatics (e.g., Bedrosian's Discourse Skills Checklist) as 20% of autistics is nonverbal, 50% develops some usable spoken language, and 30% develops fluent spoken language; another major prognostication factor.

Adaptive functioning assessment then follows-using e.g., Sparrow's Vineland Adaptive Behavior Scales where cognitive-adaptive disparity might be evident.

Medical/neurological evaluation is mandatory.

• Head circumference (e.g., microcephaly in Rett's), dysmorphism in syndromic ASD (e.g., phakomatosis, mitochondrial encephalopathy)

• Electroencephalography -for epileptiform discharges or seizures (typically bimodal, 8-21.5% have epilepsy and more in females)[3] also indicated in regression and Landau–Kleffner syndrome

• ENT evaluation should be done using audiometry

• Genetic testing includes FMR-1, TSC, and MeCP-2. Array comparative genomic hybridization detects deletion/duplication syndromes and copy number variants identifying 7%–10% of ASD

• Aberrant eating (food selectivity and abnormal stool pattern in 70%) and sleeping patterns (polysomnography might be indicated) should be noted and finally dental hygiene should be checked. Lead level might be measured with suspected pica.

Occupational therapy assessment would include Praxis, Dunn's sensory profile, and activities of daily living.

Psychiatric comorbidities should be probed using Aman's Aberrant Behavior Checklist – 70% with at least one comorbidity and 41% with two or more.[4] These include tics (22%), anxiety/mood (30%–40%), ADHD symptom profile (31%–55%), irritability (tantrums, aggression, and self-injury), aberrant sleep pattern (45%–86%), inappropriate sexual behavior, or catatonia (4%–17%).

Neuropsychological assessment might be helpful for Executive Dysfunction (e.g., Delis–Kaplan Executive Function System), contributing to social development in ASD (with weak central coherence and theory of mind).

Functional behavioral assessment including antecedents, behaviors, consequences should be applied for problem behaviors.

Outcome measures might be applied periodically - e.g., Cohen's Pervasive Developmental Disorders Behavior Inventory (parents’ and teachers’ forms) or Rimland's Autism Treatment Evaluation Checklist to evaluate treatment outcome.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.