Procedure of Rutter's study
Rutter et al followed a group of 165 Romanian orphans to test to what extent good care could make up for poor early experiences in institutions. He grouped the Romanian orphans into those who were adopted while under 6 months, between 6 months and 2 years, and those older than 2.
Physical, Cognitive and Emotional development was assessed at ages 4, 6, 11 and 15 years old.
A group of 15 English children adopted around the same time served as a control group.