Screening for Autism: What Can Primary Care Providers Look For?

Ruth McDonald, MD
Seattle Children’s Vice President of Medical Affairs

Autism spectrum disorder (ASD) refers to a broad range of conditions characterized by challenges with social communication and the presence of repetitive behavior.

There are seven symptoms of ASD.

Three social communication symptoms:

  1. Limited social reciprocity
  2. Decreased nonverbal communication
  3. Difficulties making relationships

Four behavioral symptoms:

  1. Repetitive speech, movements or activities
  2. Inflexibility/rigidity
  3. Intense or restricted interests
  4. Sensory differences

The symptoms can occur in a variety of combinations and with varying degrees of severity. Intellectual and language abilities vary widely, and individuals with autism can have very different strengths and challenges.

An individual must have all three social communication symptoms and at least two of the four behavioral symptoms to qualify for an ASD diagnosis. The symptoms must be present in early childhood though may not be detected until an individual is older.

There is no blood test, no brain scan, no genetic test that can diagnose autism. Clinicians make the diagnosis based on DSM-5 criteria and a review of the developmental history, parent interviews, direct interaction with the child, and school and medical records.

CHAT – early screening test

The AAP recommends CHAT (for children up to age 18 months) and M-CHAT (for older toddlers) as the standard screening test. Screening for ASD is recommended at well child visits until at least age 3 using these assessments.  Better screening tests for higher functioning children are in the pipeline.

Some children with ASD are easier to identify and can be diagnosed by many providers in the community, while others have a complex presentation and require specific expertise. Adequate evaluation is needed to determine the child’s primary obstacles to development so recommendations for treatment can be made.

Some early signs of autism that could signal a referral for an evaluation can include:

  • Delays in language development without attempts to communicate using gestures or other nonverbal communication.
  • Decreased response to name being called and other attempts to gain and sustain attention
  • Decreased eye contact and difficulty with social engagement
  • Presence of unusual behaviors that are repetitive, including motor movements, speech patterns or play behaviors.
  • A regression or loss of skills at any time

Here are some tips for sharing concerns with a caregiver about their child’s development:

  • Acknowledge and validate the caregiver’s concerns
  • Use developmental delays as a context for voicing concerns (e.g. language and communication, social delays)
  • Be specific about what signs/symptoms consistent with ASD you have observed
  • Describe what to expect for the evaluation of ASD
  • Make referrals for intervention (Birth to Three, school, community) and provide resources. Remember that a diagnosis is not required to begin Birth to Three or school services!



Editor’s note: WCAAP is offering a free Great MINDS-AS3D autism screening e-learning course. Learn more and register on our Webinars page.