With the MacArthur–Bates Communicative Development Inventories (CDIs), professionals can tap into parents' day–to–day knowledge about their children's language and communication skills. CDI–III, an extension of the CDIs for children 30—37 months of age, is a short, single–sheet tool that measures expressive vocabulary and grammar.
Author: Philip S. Dale Ph.D. Board Members: Philip S. Dale Ph.D., Larry Fenson Ph.D., Donna Jackson-Maldonado Ph.D., Virginia A. Marchman Ph.D., J. Steven Reznick Ph.D., Donna J. Thal Ph.D.