Which tool is commonly used for the diagnosis of autism in toddlers?

The Autism Diagnostic Observation Schedule (ADOS) is widely recognized as a critical tool for diagnosing autism spectrum disorder (ASD) in toddlers. This semi-structured assessment involves direct observation and interaction with the child, focusing on social communication, play, and other behaviors associated with autism. Its structured nature allows clinicians to evaluate a range of behaviors and skills in a standardized way, ensuring a reliable assessment that can identify signs of autism.

While other tools like the Social Communication Questionnaire and the Behavior Assessment System for Children may also contribute useful information about a child's development or communication skills, they are not specifically designed for the comprehensive diagnosis of autism. The Child Behavior Checklist serves a different purpose, focusing more broadly on behavioral and emotional problems rather than specifically diagnosing autism.

Thus, the ADOS stands out as the most effective and widely utilized diagnostic tool for autism in young children, making it the correct choice in this context.