Universally, diagnosing an autistic person can be done in two steps:
Developmental Screening:
a short test to tell if children are learning basic skills when they should, or if they might have delays. During developmental screening the doctor might ask the parent some questions or talk and play with the child during an exam to see how she learns, speaks, behaves, and moves. A delay in any of these areas could be a sign of a problem.
Comprehensive Diagnostic Evaluation:
A thorough review that may include looking at the child’s behaviour and development and interviewing the parents. It may also include a hearing and vision screening, genetic testing, neurological testing, and other medical testing.