Private school students have no academic edge over students in the public system, study finds.

Research says intelligence doesn’t depend on the school a child attends.

Australian researchers have confirmed a growing body of international research that finds the high cost of private school education does not give students an academic edge over their public school counterparts.

The study, which has been published in the Australian Journal of Labour Economics, found that once the more privileged backgrounds of private school students are taken into account, they fare no better in the education system than other children.

The research from the University of Queensland, the University of Southern Queensland and Curtin University examined the vexed issue facing many parents when choosing between a public or private education for their children.

Co-author of the study, Professor Luke Connelly, said primary students do just as well academically in either system.

“We’re looking at primary school kids here, these are kids in years three and five,” he said.

“And so this is the first study of its kind for Australia that shows at this young age that there are no differences between Catholic, independent and public schools.

“There’s actually some poorer outcomes for kids at Catholic schools interestingly. That’s also been mirrored in the international literature. There are some slighter poorer outcomes.

“An exception for kids in Catholic school is that some of the behavioural issues that we also look at, including in this case peer to peer relationships, the performance seems slightly better for Catholic school kids.

“But other than that, we don’t actually see any appreciable differences in academic performance.”

Some in the independent education sector dismissed the research while others argued the research took an “overly simplistic” view.

Yvonne Luxford, executive director of the Independent Schools Council of Australia, questioned the results.

“Even the preschool testing that they did in the paper, it shows that on the raw results there, the children in independent schools did score higher,” she said.

Related: Public or private schools: Which do we choose?

Ron Gorman from the Association of Independent Schools of Western Australia said one survey that looked at academic merit did not go far enough.

“When looking at results, it can be an overly simplistic view of what constitutes success because the measures are actually quite narrow,” he said.

David Robertson from the Queensland Independent Schools Association said the choice to send your child to a private school was centred on the individual needs of the child and not primarily academic results.

“The reason they make that sacrifice is they believe what those independent schools provide, in educational opportunities and educational programs, is what is in the best interests of their child,” he said.

Mr Robertson said parents of private school students were not paying to give their children an advantage but rather the “right” education.

“That money is parental contribution. That is what parents contribute to the costs of schooling,” he said.

“Well they’re paying to get an education they think is right for their child – that’s the point.”

The choice between public and private education may not make a difference to child performance but other factors like baby birth weight and who their parents are, is crucial.

Related: Public and private schools: 5 things you might not know

Children with a birth weight of less than 2.5 kilograms achieve significantly lower test scores later in life, particularly in grammar and numeracy.

Professor Connelly said the study found other factors that contribute to classroom performance.

“The other things that matter are the level of education of the parents, the number of books in the home, also the area – the residential neighbourhood and its characteristics – the household income, and interestingly enough as well the working hours of the mother,” he said.

“So as working hours increased for the mother, some of these test scores also decline a bit.

“And I guess that latter result really just shows some of the importance of the parental time input in relation to kids’ success at school as well.”

Meanwhile the working hours of fathers had no impact.

“We didn’t find any similar result for the males’ working hours and that’s an interesting point of difference,” Professor Connelly said.

The research also finds poorer results for school children from Indigenous backgrounds and those whose parents had not completed Year 12 at school themselves.

This article was originally published on ABC.