The original setup for the task was: The child who is seated at a table where a model of three mountains is presented in front.
On a similar note, these results help Piaget home in on what age children show the capacity to decenter their thoughts, otherwise seen in a deviation away from egocentric thinking.
[6] Conversely, children in the concrete operational stage demonstrate decentration - an ability to recognize alternate point of views and a straying away from egocentric thinking.
There has been some criticism that the Three Mountain Problem was too difficult for the children to understand, compounded with the additional requirement of matching their answer to a photograph.
When the stakes were raised and additional walls and policeman dolls were added, 90% of four-year-olds were still able to pass the task.
[7] Hughes claimed that because this task made more sense to the child (with a primer session with one police doll to guarantee this), children were able to exhibit a loss of egocentric thinking as early as four years of age.
In 1975, another researcher by the name of Helen Borke replicated the task using a farm area with landmarks such as a lake, animals, people, trees, and a building.
Hence, evaluation of Piaget's Three Mountain Problem has shown that using objects more familiar to the child and making the task less complex will produce different results than the original study.