This study investigated the phonological encoding abilities of five- and six-year old children who stutter. Results suggest that young children who stutter have subtle, yet robust, linguistic differences in certain aspects of phonological encoding that may contribute to an unstable language planning system in young children who stutter.
Pelczarski, Kristin M. & Yaruss, J. Scott. (2013). A Preliminary Examination of Phonological Encoding in Young Children Who Stutter. Journal of Fluency Disorders. doi.org/10.1016/j.jfludis.2013.10.003