There are no formal tests to measure or diagnose ToM. However, there are several techniques that can give your child’s evaluator an idea of the level of ToM your child has developed. One such technique is the Smarties task.
In the Smarties task, the child is shown a container of Smarties candies, or another type of highly recognized candy container. The child is asked what is inside the container, with the expected answer to be “Smarties candies.” The examiner opens the container and instead of Smarties, coins come out. The child is then told that their mother is going to be shown the Smarties container and the child is asked what she thinks her mother will say. Children who have ToM say their mother will guess that the container has Smarties in it. Children without ToM will say their mother will say the container has coins in it.
Asperger’s Disorder children do not understand that their mother does not know the examiner has played a trick and put coins in the container instead of the candy. They do not understand the difference between what they know and what the other person knows.