The relationship between low family income and psychological disturbance in young children: an Australian longitudinal study

Objective: This study examines the relationship between low family income (LFI) experienced at different points in time, chronic low income status and its impact on child behaviour measured at 5 years of age. Method: Longitudinal data from the Mater University Study of Pregnancy were used to measure LFI in families at three points in time (the antenatal period, 6 months post birth and at 5 years cf age). Outcome variables were three independent groups of behaviour problems labelled as externalising, social, attentional and thought (SAT) problems, and internalising problems. These groups were developed from the Child Behaviour Checklist. An analysis based on logistic regression modelling was carried out examining the relationship between LFI and a range of intermediate variables known to be associated with child behaviour problems, Results: The more often families experienced low income, the higher the rate of child behaviour problems at age 5. Low family income was still independently associated with SAT behaviour problems after controlling for smoking in the first trimester, parenting styles, maternal depression and marital dysharmony at age 5, The association between LFI and internalising and externalising behaviour problems was largely mediated by maternal depression. Conclusion: Low family income is a significant factor in the aetiology of a variety of child behaviour problems. The mechanisms involved in the link between LFI and childhood internalising and externalising behaviours involve the exposure of the children to maternal depression. However, the relationship between LFI and SAT behaviour problems remains to be elucidated.