Which is the most likely diagnosis for a socially immature 5-year-old boy who avoids eye contact and plays mechanically?

The most likely diagnosis for the described behavior of the 5-year-old boy is autism, often characterized by challenges in social communication and the presence of restricted or repetitive behavioral patterns. The key features noted in this scenario—social immaturity, avoidance of eye contact, and mechanical play—are consistent with common signs of autism spectrum disorder (ASD).

Children with autism often struggle with social interactions and may exhibit atypical social behaviors, such as avoiding eye contact, which is partly due to difficulties in social reciprocity and a difference in social awareness. The mention of "mechanical play" suggests that the child may engage in repetitive or focused activities rather than imaginative or interactive play, another typical aspect of children on the autism spectrum.

In contrast, while the other diagnoses might share some elements with these behaviors, they do not fully encompass the breadth of symptoms observed in this child. For example, normal development in a 5-year-old wouldn’t typically include such pronounced social avoidance or mechanical play patterns. Social phobia involves excessive fear of social situations but doesn't usually manifest with the same level of mechanical play or lack of eye contact seen in this child. Avoidant personality disorder is typically not diagnosed in children as it applies to older adolescents or adults who show pervasive and enduring