<p class="first" id="P1">The present study tested specific hypotheses advanced by
the developmental propensity
model of the etiology of conduct problems in the Colorado Longitudinal Twin Study,
a prospective, longitudinal, genetically informative sample. High negative emotionality,
low behavioral inhibition, low concern and high disregard for others, and low cognitive
ability assessed during toddlerhood (age 14 to 36 months) were examined as predictors
of conduct problems in later childhood and adolescence (age 4 to 17 years). Each hypothesized
antisocial propensity dimension predicted conduct problems, but some predictions may
be context specific or due to method covariance. The most robust predictors were observed
disregard for others (i.e., responding to others’ distress with active, negative responses
such as anger and hostility), general cognitive ability, and language ability, which
were associated with conduct problems reported by parents, teachers, and adolescents,
and change in observed negative emotionality (i.e., frustration tolerance), which
was associated with conduct problems reported by teachers and adolescents. Furthermore,
associations between the most robust early predictors and later conduct problems were
influenced by the shared environment rather than genes. We conclude that shared environmental
influences that promote disregard for others and detract from cognitive and language
development during toddlerhood also predispose individuals to conduct problems in
later childhood and adolescence. The identification of those shared environmental
influences common to early antisocial propensity and later conduct problems is an
important future direction, and additional developmental behavior genetic studies
examining the interaction between children’s characteristics and socializing influences
on conduct problems are needed.
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