Phonological process development with MLU-referenced guidelines.

Sixty subjects between the ages of 21 and 48 months were placed into groups based on mean length of utterance (MLU) and chronological age (CA) to test Stampe's hypothesis about the development of phonological processes. The subjects were given the Phonological Process Analysis (Weiner, 1979), and a proportion score for each of sixteen phonological processes was derived for each subject. The use of the various phonological processes across MLU groups and age groups was analyzed by multiple regression correlation, three-way ANOVA, and Tukey's HSD tests. MLU was found to be the best classification for the subjects for describing the phonological processes. The results and discussions present MLU-referenced guidelines regarding the emergence, duration, elimination, and universality of the sixteen phonological processes.