The Peabody Picture Vocabulary test is a cross modality task.
For example, to the stimulus phrase in the Receptive test, "Do cup cakes wink?" the child is to respond by saying Yes or No.
This is a more complex response than raising a finger or pointing, and hence involves a bit more processing on the expressive side.
But in the eyes of the test developers, This is not a significant problem.
In our ideal model, the tasks were all single modality tasks, but in many tests, the tasks cross modalities.
In the Peabody Picture Vocabulary test, for example, the child hears the word and selects a corresponding picture in a book. This is a task which spans the auditory and visual modalities.
NOTES: A reference for the Peabody Picture Vocabulary Test (PPVT).