Having older parents may positively affect children's behaviour

Children of older parents display an equal or lower number of behavioural problems such as aggression and defiance relative to their peers with younger parents. These findings emerge from a study that was published recently in the journal Child Development. It is well known that greater parental age increases a child's risk of physical neurological abnormalities, but this advanced age has now been revealed to have an opposite and positive effect on the mental constitution of the child. This study is the result of collaboration between multiple universities within the Consortium on Individual Development (CID) .

As it turns out, parents have no reason to fear that their own age will negatively affect the child in terms of behavioural problems – quite the contrary, in fact. The expectation was that if the age of the parents were to play a role, greater age would have a detrimental effect. This situation proved not to be the case. 'If a correlation exists between the behaviour of children and the age of their parents, older parents tend to have children with fewer behavioural issues', explains Mariëlle Zondervan-Zwijnenburg (UU), one of the lead authors.

If a correlation exists between the behaviour of children and the age of their parents, older parents tend to have children with fewer behavioural issues

Unique data

The new research made use of data on 32,893 Dutch children, which had been collected as part of multiple large-scale studies over the course of several years. All data were gathered with the aid of people close to each child: teachers, fathers, mothers and the children themselves. As a result, it was possible to gain an understanding of the children's behaviour in a variety of situations. 'This element makes the study extremely reliable', according to Zondervan. 'It enabled us to form a solid picture, independent of the parameters and measurement methods of the individual studies.'

Statisticians in this project applied exciting new statistical approaches, allowing us to find evidence which supports the hypothesis that older parents have children with fewer problems

One unique aspect is that this wealth of data was combined through partnerships between multiple universities within the CID. Utrecht University, Vrije Universiteit Amsterdam, Erasmus University Rotterdam and UMC Groningen all collaborated in the project. Dorret Boomsma, co-lead author (VU): 'The cooperation between multiple universities enabled us to study children from all across the Netherlands. Statisticians in this project applied exciting new statistical approaches, allowing us to find evidence which supports the hypothesis that older parents have children with fewer problems.'