Abstract

Determined month-by-month norms for comprehension and production of 396 words from 8 to 16 mo, and production of 680 words from 16 to 30 mo, derived from a norming study of 1,789 children aged 8-30 mo that used the Communicative Development Inventories. The norms are available in the form of a database program, LEX, for MS-DOS-based computers.