Foster care leads to sustained cognitive gains following severe early deprivation.
Level 2 - randomized trial
Longitudinal follow-up of a randomized controlled trial
PubMed 36095188 · doi:10.1073/pnas.2119318119
What was done
Longitudinal follow-up of 135 participants at age 18 from the Bucharest Early Intervention Project, a randomized controlled trial comparing high-quality foster care to institutional care as usual following severe early psychosocial deprivation. Cognitive ability (IQ) was assessed 16 years post-randomization, alongside mediation analyses evaluating caregiving quality and attachment security, and exploratory analyses assessing placement stability.
What was found
Sixteen years after randomization, participants in the foster care arm had significantly higher IQ scores (9 points, 0.6 standard deviations) compared to those in the care-as-usual group. Mediation analyses demonstrated that the cognitive benefit was partially explained by higher-quality caregiving and attachment security. Exploratory analyses indicated that stable placements throughout childhood correlated with the greatest cognitive gains.
Why it matters
These findings provide experimental evidence that early transition from institutional deprivation to family care produces cognitive benefits lasting into early adulthood. They also support high-quality caregiving and secure attachment as vital targets for early developmental interventions.
Limits
The sample is modest (n = 135) and limited to individuals exposed to severe early institutional deprivation in Romania, which may limit generalizability to other populations or less severe neglect. Specific p-values, confidence intervals, and attrition rates are omitted from the abstract.