Autism is typically diagnosed through a comprehensive evaluation conducted by healthcare professionals who specialize in developmental disorders. 

The diagnostic process may involve several steps, including:

Developmental Screening:
 Healthcare providers may administer a brief developmental screening tool to identify any early signs of autism. This can be done during routine well-child visits or if concerns are raised by parents or caregivers.

Comprehensive Diagnostic Evaluation: 
If the initial screening suggests a possibility of autism, a more in-depth evaluation is conducted. This evaluation involves gathering information about the child's behavior, development, and medical history. It may include interviews with parents or caregivers, direct observation of the child, and standardized assessments.

Multidisciplinary Team Assessment: 
Autism diagnosis often involves a multidisciplinary team of professionals, such as pediatricians, psychologists, speech-language pathologists, and occupational therapists. 

Each professional brings their expertise to assess different aspects of the child's development and behavior.

Diagnostic Criteria: 
The diagnostic process follows criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association. 

The DSM-5 provides specific criteria and guidelines for diagnosing autism spectrum disorder (ASD).

Differential Diagnosis: 
During the evaluation, the healthcare professionals consider and rule out other possible causes or conditions that may be associated with similar symptoms to ensure an accurate diagnosis.

Feedback and Recommendations: 
Once the evaluation is complete, the healthcare professionals will provide feedback, share the diagnosis, and discuss the implications. 

They may also provide recommendations for interventions, therapies, and support services that can help the child and their family.

It's important to note that early diagnosis and intervention are crucial for children with autism. If you suspect that your child may be showing signs of autism, it is recommended to consult with healthcare professionals experienced in diagnosing and treating autism spectrum disorder. They can guide you through the diagnostic process and help develop an appropriate intervention plan based on your child's specific needs.