Thirty children are randomly assigned to one of two contexts and one of three item lists, with five children in each combination. Each child is read the words in his/her item list and asked to say...

Thirty children are randomly assigned to one of two contexts and one of three item lists, with five children in each combination. Each child is read the words in his/her item list and asked to say whether it is being mispronounced. Children in the picture context are shown pictures of the items as they are being read. Children in the no-picture context are not shown pictures. The dependent variable was number correct. The first question asked by the researchers was whether the item lists were, on average, of equal difficulty Bower and Hirakis (2006).