Quantity of communicative behavior in children from birth to 30 months.

68 normal children were observed during play interaction with their mothers. Children's communicative acts were coded according to form and function, based on seven levels of communicative competence. Seven age groups, corresponding to the developmental predominance of each, were formed from birth to 30 mo. Each included equal numbers of girls and boys. Total number of communicative acts were determined for each child. Girls produced significantly more communicative output than boys. Verbal children produced significantly more output than preverbal children. There were no significant differences between preverbal groups or between verbal groups. The results are discussed relative to other research.