Continuous tracking of behavioral development in infants

Infant development scales provide a one time measure of the number of scale items an infant performs and his standing relative to his age group. Repeated assessment indicates how many more items he can perform and whether his relative status has altered but does not measure actual changes in the same behaviors as development progresses. This paper discusses the importance of continuously measuring the same behavior over time as an alternative strategy. The developmental information is exemplified by the behavioral records of two infants observed over a 25-week period for changes in frequency and duration of three prone position motor responses.