While there is definitely evidence that autism initially begins in during fetal development and becomes more apparent around 15 to 30 months old or older, screening is not perfect around this time because of a wide developmental spectrum. A diagnosis of autism would likely occur later in a child's life. The best way to know if your child has autism is to keep an eye on it for developmental problems and to bring up issues at your child's check-ups at the doctors office. There is no test for autism, just a screening process that can help determine whether your child might have a check-list of diagnostic markers for autism. Those screening tests should be given at the 9 month check up, 18 month check-up, and around the 24 or 30 month check up.

If your doctor discovers some evidence of developmental issues or if the child is at high risk for autism (such as if there is an autistic parent or sibling), there is an autism-specific screening test to determine whether the developmental issues are, in fact, symptomatic of autism. After all, autism is just one pervasive developmental disorder.

Part of the reason that screening has to start so early is that early intervention may retard or influence the development of autism over time. It also enables parents to prepare themselves for raising an autistic child, which has to be different than the way one might raise a neurotypal child due to the differences in processing information, emotions, social situations, and change. Screening has also improved over the years to include screen tests for high-functioning autism and Asperger's syndrome. However, these screenings are not perfect. They point out children who might have trouble during their development or who have delays in their development. However, they are not good enough to act as evidence and so cannot make a definite diagnosis, which is why if screening yields a suggestion of developmental delays, further evaluations are needed with specialists trained to recognize the intricacies of autism. At this point, you request a transfer to a developmental pediatrician or another kind of specialist in order to reach a more credible diagnosis.

This next step is a complex evaluation studying the individual through clinical observation, parental anecdotes, speech/language assessments, psychological evaluation, medical histories, several autism specific tests covering all bases, including genetic tests, medical tests, and neurological tests. The reason for the amount of effort put into the evaluation of autism is that autism is an incredibly complex and varied disorder. This is part of the reason that there is no single easy evaluation for autism - instead, many different evaluations and tests provide a more comprehensive picture of autism.

It is undeniably difficult to broach questions on whether your child might have autism, but the best way to provide effective screening is to be prepared to ask questions and give observations to your pediatrician. Keep records and inform yourself on the nature and signs of autism. Not all pediatricians automatically offer a developmental evaluation, so do not hesitate to request one should you have suspicions about your child.