Assessing the intellectural consequences of early intervention with high-risk infants.

Infants at-risk for mental retardation were divided into a group that received early day-care intervention and a matched control group that did not. The purpose of the intervention was to prevent sociocultural retardation. Children were tested at 7 and 18 months on a simple two-choice visual-discrimination task and on the Bayley Scales of Infant Development to assess the impact of the intervention program on their development. Analyses revealed that the experimental group's performance was reliably superior to that of the control group on both measures and that experimental subjects scoring high on the Bayley Scales reached criterion on the discrimination task on fewer trials than low Bayley scorers. The relationship was particularly strong at 18 months.