MLU (Mean Length of Utterance)
Mean Length of Utterance (MLU) is a commonly used measure in the study of language development and in clinical practice. Invented in the 1960s by Roger Brown and his colleagues, it has served for 60 years as a method of comparing children's language samples and inferring how far along the road to language mastery children have traveled. However, many have questioned the use of MLU alone in measuring grammatical development. This is especially true for young toddlers producing their first phrases and sentences, which may have the same length, but varying complexity. Explore the workings of MLU, what it captures and what it misses in this brief video.