A critique of research examining whether early experiences with primary caregivers are reflected in adaptation is that relevant longitudinal studies have generally not employed genetically informed research designs capable of unconfounding shared genes and environments. Using the twin subsample (N = 485 pairs) of the Early Childhood Longitudinal…

Three waves of data from a prospective longitudinal study in Sierra Leone were used to examine internalizing trajectories in 529 war-affected youth (ages 10-17 at baseline; 25% female). Latent class growth analyses identified 4 trajectories: A large majority of youth maintained lower levels of internalizing problems (41.4%) or significantly…

Nationally, 15% of children younger than 5 years regularly attend more than 1 child-care arrangement. An association between arrangement multiplicity and children's behavior problems has been identified, but previous research may be susceptible to measurement or omitted variable bias. This study used within-child fixed effects models to examine…