A new study suggests that children with autism are seen as less friendly and less trustworthy by their peers, based solely on their appearance.

The research, published in the journal Autism, suggests that typically developing children are less positive towards children with autism and form negative impressions after just a 30-second encounter.

Dr Steven Stagg of Anglia Ruskin University, and psychologists at Royal Holloway, University of London, investigated the initial impressions that typically developing children form when watching silent videos of children with autism.

The researchers mixed silent videos of typically developing 11-year-olds with videos of children with autism of a similar age. They then asked 44 school children (aged 11) to rate the children in the video, who were unaware that some of the children they were watching had a diagnosis of autism.

Children with a diagnosis of autism were rated lower on nearly all of the measures. They rated the children with autism as less trustworthy than the typically developing children, they were less likely to want to play with them and less likely to want to be their friend.

Dr Stagg, Senior Lecturer in Psychology at Anglia Ruskin, said: "Poor expressivity has been documented in autism, but our research demonstrates that this can have a significant impact on forming first impressions.

"Children with autism spend many years learning about facial expressivity, but our research shows that by the age of 11 their slower development in this area is already marking them out amongst their typically developing peers.

"Children with autism have a difficult time at school, and research published by The National Autistic Society showed that 40% of children with autism reported being bullied.

"According to the Department for Education, 71% of children with an autism diagnosis are currently educated in mainstream schools. It is therefore important that schools work with typically developing children to educate them about autism, in order to break through the negative impressions that can be formed through a moment's contact."