Screening & Diagnosis (0–6 Years)

Why Early Screening Matters

The first six years of a child's life are a critical period for brain development. During this time, early identification of developmental differences can significantly improve a child's long-term outcomes. Autism Spectrum Disorder (ASD) can often be recognized in the first two years of life, and early screening allows children to receive timely evaluation, intervention, and family support.

Research consistently shows that children who receive early, evidence-based intervention demonstrate better progress in communication, social interaction, learning, adaptive behaviour, and independence.

Developmental Surveillance vs. Autism Screening

Developmental Surveillance

Developmental surveillance is an ongoing process carried out by parents and healthcare professionals during routine health visits. It involves observing whether a child is meeting expected developmental milestones in areas such as:

Communication and language
Social interaction
Play skills
Motor development
Cognitive development
Behaviour and emotional regulation

Parents are often the first to notice developmental differences and should feel confident discussing their concerns with healthcare providers.

Autism-Specific Screening

Autism screening uses standardized questionnaires to identify children who may require a comprehensive developmental evaluation. Screening does not provide a diagnosis but helps identify children who need further assessment.

Routine autism screening is generally recommended at:

18 months
24 months

Screening should also be conducted whenever parents, caregivers, teachers, or healthcare professionals have concerns about a child's development.

Common Early Signs (0–6 Years)

Parents should seek professional advice if a child shows one or more of the following signs:

By 12 Months

Limited eye contact
Rarely smiles back at others
Does not consistently respond to their name
Limited babbling
Does not point, wave, or use gestures
Limited interest in social games like peek-a-boo

By 18–24 Months

Delayed speech or loss of previously acquired words
Limited imitation of others
Does not point to share interests
Prefers playing alone most of the time
Repetitive movements such as hand flapping or rocking
Unusual reactions to sounds, lights, textures, or touch
Difficulty coping with changes in routine

Preschool Years (3–6 Years)

Difficulty making friends
Challenges with conversation and social interaction
Limited imaginative or pretend play
Highly restricted interests
Repetitive behaviours or routines
Strong sensory sensitivities
Emotional regulation difficulties

Every autistic child is different. Some children may show only a few of these signs, while others may have more noticeable developmental differences.

The Diagnostic Process

There is no single blood test, brain scan, or laboratory test that can diagnose autism. Diagnosis is based on a detailed assessment of a child's development, behaviour, communication, and social interaction.

A comprehensive evaluation may include:

Developmental history
Parent interviews
Clinical observation
Standardized autism assessment tools
Speech and language evaluation
Cognitive and developmental assessment
Occupational therapy assessment (when needed)
Hearing and vision assessments to rule out other causes

Diagnosis should be performed by trained professionals such as developmental paediatricians, child psychiatrists, clinical psychologists, or multidisciplinary autism assessment teams.

Common Screening Tools

Healthcare professionals may use validated screening tools, including:

Modified Checklist for Autism in Toddlers, Revised with Follow-Up (M-CHAT-R/F)
Social Communication Questionnaire (SCQ)
Ages and Stages Questionnaires (ASQ)
Parents' Evaluation of Developmental Status (PEDS)

These tools help identify children who need further assessment but do not confirm an autism diagnosis.

Diagnostic Assessment Tools

Professionals may use internationally recognized assessment tools such as:

Autism Diagnostic Observation Schedule (ADOS-2)
Autism Diagnostic Interview-Revised (ADI-R)
Childhood Autism Rating Scale (CARS-2)
Developmental Profile assessments
Cognitive and adaptive behaviour assessments

Diagnosis should always combine clinical expertise with information from parents, caregivers, and educators.

What Happens After Diagnosis?

Receiving an autism diagnosis is the beginning of understanding a child's strengths and support needs—not the end of their journey.

Families should be supported with:

Early intervention services
Speech and language therapy
Occupational therapy
Parent training programmes
Educational planning
Behavioural and developmental support
Family counselling and peer support groups

Children do not need to wait for a disability certificate before beginning intervention. Early support should begin as soon as developmental concerns are identified.

Guidance for Parents

If you are concerned about your child's development:

Trust your instincts.
Do not adopt a "wait and see" approach if concerns persist.
Speak with your child's paediatrician or developmental specialist.
Request developmental screening and, if needed, a comprehensive autism evaluation.
Keep records of your child's developmental milestones and behaviours.
Seek evidence-based interventions from qualified professionals.

Remember, an early diagnosis provides access to services, educational planning, and family support that can positively influence your child's development.

Trusted Resources

Parents and professionals are encouraged to consult evidence-based guidance from:

International Guidelines

World Health Organization (WHO)
American Academy of Pediatrics (AAP)
National Institute for Health and Care Excellence (NICE), UK
Centers for Disease Control and Prevention (CDC)

Indian Resources

National Institute for Empowerment of Persons with Intellectual Disabilities (NIEPID)
All India Institute of Medical Sciences (AIIMS)
National Trust, Government of India
Rehabilitation Council of India (RCI)

Key Message

Early screening saves time. Early diagnosis opens doors. Early intervention changes lives.

If you notice developmental differences, do not delay seeking professional advice. Every month matters during early childhood, and timely support can help children build communication, learning, social, and life skills that will benefit them throughout their lives.