Dependent Variables
We organized children’s developmental outcomes into two dimensions: first, measures
associated with children’s mental and motor development; second, measures associated
with children’s social/interaction or behavioral development. Direct child assessments of
infants at 9 months were conducted with the Bayley Short Form–Research Edition (BSF-R)
in mental and motor domains and with the Nursing Child Assessment Teaching Scale
(NCATS), which measures parent–child social interaction. Data from items of the Behavior
Rating Scale (BRS) were gathered through a combination of examiner observation and
questions to the parent. Finally, the Infant/Toddler Symptom Checklist (ITSC) relies on
parental report.