Fostering security? A meta-analysis of attachment in adopted children

Adopted children are hypothesized to be at risk of insecure attachment relationships because of their background of institutional care, maltreatment and neglect. We conducted two series of meta-analyses, one using only observational assessments of attachment and one using both observational and self-report assessments. Observational assessments showed that children who were adopted before 12 months of age were as securely attached as their non-adopted peers, whereas children adopted after their first birthday showed less attachment security than non-adopted children (d = 0.80, CI = 0.49–1.12). Regarding the overall effect for attachment security, adoptees were comparable to foster children. Adopted children showed more disorganized attachments compared to their non-adopted peers (trimmed d = 0.36, CI = 0.04–0.68), but again were comparable to foster children (trimmed d = 0.35, CI = 0.02–0.67). Compared to institutionalized children, adoptees were less often disorganized attached. When self-report measures of attachment were included no difference was found between adoptees and their non-adopted counterparts (trimmed d = 0.12, CI = − 0.02–0.26, 39 studies, N = 2912 adopted children). Compared to institutionalized children, (early) adoption proves to be an effective intervention in the domain of attachment.