A study by Montreal University researchers notes that physical aggression problems can be traced to early childhood, and studies have shown that low levels of maternal education are among the best predictors of high physical aggression from early childhood to adolescence.
The team, led by Sylvana M. Côté, has published its findings in the November issue of the Archives of General Psychiatry.
The study however found that among children of mothers with low education levels, those who received regular care from other adults during preschool years might be less likely to have problems with physical aggression.
The team studied 1,759 infants representative of all children born in Quebec in 1997 or 1998. Mothers were interviewed yearly from the time the children were aged five months to 60 months, answering questions about family, parent and child characteristics and behaviour.
This included details about non-maternal care services, provided to care for a child, usually while the mother was working.
Children whose mothers had a low education level (less than high school) were less likely to receive day care. However, children who did receive non-maternal care had lower levels of physical aggression.
Children of mothers who graduated from high school were at lower risk of developing physical aggression problems, and non-maternal care had no additional effect on their behaviour.
"We provide robust evidence that the provision of non-maternal care services to children of mothers with low levels of education could substantially reduce their risk of chronic physical aggression, and that the protective impact is more important if children begin to receive these services before the age of nine months," the authors wrote.