Appleyard et al.
ABSTRACT
Background: Cumulative risk research has established the deleterious effects of co-
occurring risk factors on child behavior outcomes. However, extant literature has not
addressed potential differential effects of cumulative risk at different points in development
and has left open questions about whether a threshold model or a linear risk model better
describes the impact of cumulative risk on behavior outcomes. The current study examined
the impact of cumulative risk factors (i.e., child maltreatment, inter-parental violence, family
disruption, low socioeconomic status, and high parental stress) in early and middle childhood
on child behavior outcomes in adolescence. Methods: Using data from an ongoing
longitudinal study of at-risk urban children (N ¼ 171), the cumulative effects of these five risk
factors across early and middle childhood were investigated. Results: The findings support
the cumulative risk hypothesis that the number of risks in early childhood predicts behavior
problems in adolescence. Evidence for a linear but not a threshold model of cumulative risk
was found; the more risks present, the worse the child outcome. Moreover, the presence of
multiple risks in early childhood continues to explain variations in predicting adolescent
behavior outcomes even after including the effects of risk in middle childhood. Conclusions:
The results support the need for comprehensive prevention and early intervention efforts with
high-risk children, such that there does not appear to be a point beyond which services for
children are hopeless, and that every risk factor we can reduce matters. Keywords:
Cumulative risk, internalizing behavior, externalizing behavior. Abbreviations: EC: early
childhood; MC: middle childhood; IPV: inter-parental violence; SES: socioeconomic status;
LES: life stress; CBCL: Child Behavior Checklist.
Wetenschappelijke relevantie
Past research strongly suggests that factors such as child maltreatment, inter-
parental violence, family disruption, poverty, and life stress have a negative impact on
children’s development. Even though many of these risk factors co-occur, they have
yet to be investigated in terms of their cumulative effects over time.
The cumulative risk hypothesis asserts that the accumulation of risk factors, independent of
the presence or absence of particular risk factors, impacts developmental outcomes, such
that the greater the number of risk factors, the greater the prevalence of clinical problems.
Rochester Longitudinal Study (RLS)
Rutter and colleagues initially identified six risk factors significantly correlated with
childhood psychiatric disorders: (1) severe marital discord; (2) low social status; (3)
large family size; (4) paternal criminality; (5) maternal mental disorder; and (6) foster
placement. Moreover, their findings revealed the increased effects of an accumulation
of risk factors, such that while no single risk factor significantly increased risk for
disorder, the presence of two risk factors contributed a fourfold increase in the
likelihood of mental disorder, and the presence of four risk factors yielded a tenfold
increase.
The environmental risk factors included: (1) history of maternal mental disorder; (2)
high maternal anxiety; (3) rigid parental attitudes, beliefs, and values about child
development; (4) observations of few positive parent–child interactions; (5) unskilled
occupational status; (6) low maternal educational status; (7) disadvantaged minority
status; (8) single parenthood; (9) stressful life events; and (10) large family size
(Sameroff, 2000). The RLS revealed that the number of risk factors was associated
both with concurrent behavior problems in preschool as well as with adolescent
mental health, problem behavior, and academic problems.
Two models of cumulative risk
Threshold / quadratic effect: after a certain number of risk factors are experienced, a
dramatic increase in problem behavior outcomes occurs in a quadratic fashion. In this