There is no “one-stop” evaluation, like a blood test, that can verify the presence of an autism spectrum disorder (ASD). Diagnoses of ASDs must be made based on evaluations of a child’s behavior, social skills, and ability to communicate. A confirmed diagnosis requires two steps.

Routine Testing

First, the family doctor or pediatrician should perform routine tests during regular visits that measure the pace of a child’s development. These checks are called developmental screening tests, during which the doctor measures how well a child is developing in the areas that can be affected by ASDs. This can bring potential signs of an ASD or other issue to light.

Developmental Tests

Developmental tests, meant to specifically find ASDs, should be performed by the doctor at the 18- and 24-month checkups. More tests than these may be done if the child is at higher risk of having ASDs, or for other reasons such as premature birth or a low birth weight.

Comprehensive Testing

If these initial rounds of screening spot problems, then the second step, involving comprehensive testing by specialists, is carried out. These examinations are designed to pinpoint what is going on—whether it is an ASD or something else. Some conditions have similar symptoms to autism and there can also be other disorders or conditions present in addition to autism.

The enhanced testing can include genetic and neurological testing as well as more measures of the child’s behavior, and communication and social skills.

Child Behavior

At both levels of testing, the parents will be questioned by the investigators and their observations of their child’s behavior in daily life can be very helpful in determining whether an ASD is present. The National Institute of Mental Health suggests reviewing picture albums and video recordings of the child to try to spot signature behaviors or when the child should have reached certain developmental benchmarks.

Early diagnosis can be the key to successfully dealing with the issues a child faces because of ASDs. Spotting an ASD early on can mean quicker enrollment in programs that help the child learn the skills he or she needs to cope with ASD. Consensus is that the earlier an autistic person is enrolled in a program, the better the outcome.

Educational Diagnosis

Qualified school officials can also make what is called an educational diagnosis. This is not the same as the medical diagnosis. Instead, it is done to determine what needs and services can be provided to a child in the school environment. This diagnosis is not necessarily dependent on a medical diagnosis.

Often, the first ones to notice potential problems are a child’s parents. If you think something might be wrong with your child, tell your doctor.