This study provided a 5-year follow up on the progress of the children in the landmark study by Lovaas (1987). Specifically, we evaluated intellectual functioning, relationships with family members, independent functioning, use of leisure time, and socialization with peers through standardized measures. This study found that the results reported in the Lovaas (1987) study maintained for those individuals who received 40 hours or more per week of intensive behavioral intervention. That is, gains in IQ and adaptive behavior and decreases in maladaptive behaviors were only maintained for those individuals who received intensive behavioral intervention.
