One of the perennial questions parents face, when deciding where to send their children to school, is whether government or non-government schools achieve the best results. Given the financial commitment involved it is only natural to ask which school sector achieves the strongest outcomes.
Judged by recent comment pieces in the Fairfax Press like 'No academic advantage in private schooling' and 'Public, private schools give same results, 30 studies show' it appears that the evidence is clear.
In the first comment piece Tim Dodd cites a study by researchers at the University of Queensland outlined in the Australian Journal of Labour Economics that argues "the returns to attending private schools are no different to those attending public schools".
Trevor Cobbold in the second Fairfax piece argues there are "no significant differences between the results of students from public, Catholic and Independent schools".
Add that the same argument is put in a recent piece on The Conversation website, titled 'Studies consistently find no academic gains from private schooling, but don't explain why', and parents could be forgiven for thinking there is no advantage in choosing a Catholic or an independent school.
Why choose non-government schools if the results are the same?
Reality check. Instead of under performing there is widespread agreement that non-government schools, whether literacy or numeracy tests, Year 12 results or tertiary entry, with the exception of selective secondary schools, achieve the strongest results.
A 2001 study carried out by the Australian Council for Educational Research investigating Year 12 performance and tertiary entry concludes that "School sector has a substantial impact" and that Catholic and independent school students' results are between 6 to 12 points higher than government school students.
Gary Marks, a Melbourne-based researcher, in a 2004 analysis of Year 12 results reaches a similar conclusion, he writes "So a variety of studies using different sources of data all show substantial sector differences in university entrance".
Marks also argues that non-government schools are more effective at what is described as 'value-adding' – a situation where a school helps a student achieve a stronger result than what otherwise might be expected.
In a research article in the April 2009 edition of the Australian Journal of Education, Marks writes that "non-government schools relative to government schools 'add value' (between 5 to 9 percent) to student performance among those students vying for tertiary entrance between age 15 and Year 12".
Such is the evidence that even Trevor Cobbold, a strong critic of Catholic and independent schools, agrees that non-government schools outperform government schools when he concludes, "Raw comparisons of student outcomes in public and private schools generally show higher achievement in private schools".
As the saying goes, there are lies, dammed lies and statistics. Even though it's clear that Catholic and independent schools achieve the best results critics argue it's only because their students come from privileged backgrounds. After adjusting results for home background, including parental occupation, qualifications and postcode, the critics argue that any advantage non-government schools have disappears.
Wrong again. Contrary to the argument that Catholic and independent schools only do well because students are privileged the research consistently shows that non-government schools outperform state schools even after adjusting for home background.
In relation to NAPLAN results, for example, research by Paul Miller and Derby Voon from Curtin University concludes that "test outcomes vary by school sector, with non-government schools having higher school average scores, even after differences in schools' ICSEA are taken into account" (ICSEA is a measure of home background).
A 2001 study by the Australian Council for Educational Research concludes that after adjusting for socioeconomic profile and previous academic achievement, measured by Year 9 results, that students in non-government schools, on average, achieve a tertiary entry score 5 to 6 points higher than students in government schools.
While such an advantage might appear minor, in relation to highly sought after university courses like medicine and law one or two points can be decisive.
Research Report 61 associated with the Longitudinal Surveys of Australian Youth makes a similar point when concluding, in relation to tertiary entry, that 'the average socioeconomic status of students at a school does not emerge as a significant factor".
The LSAY report also notes "there is also considerable variation within school sectors, with the government sector having more than its share of low-performing schools".
In relation to school completion rates, as measured by staying on to Year 12, it's also the case that non-government schools achieve stronger outcomes. The Longitudinal Surveys of Australian Youth Report 59 concludes non-government schools have a 3 to 8 percentage point advantage.
And in relation to tertiary completion rates Sally Knipe from Charles Sturt University writes, "Data from LSAY indicates that students who had attended Catholic secondary schools are more likely to complete a university course."
As to why this is the case, the research is clear. Non-government schools set high standards, students are motivated, there is a rigorous curriculum and a disciplined classroom environment and such schools better reflect parents' expectations.
Based on his research Marks argues, "non-government schools promote a more academic environment that lifts student performance". In explaining the strong outcomes achieved by Catholic schools, Marks writes that instead of home background, "Other more credible explanations are higher levels of parental and community involvement with Catholic schools, higher standards of discipline and greater emphasis on academic performance".
And the superior performance of non-government schools does not simply relate to academic results. One Australian study, 'The impact of racism upon the health and wellbeing of young Australians' concludes that Catholic school students are more racially tolerant compared to students in government schools.
A second study, 'Long-term effects of Catholic schooling on wages', investigating what happens after tertiary studies are completed and graduates enter the workforce is that those who attended Catholic schools have a better chance of earning higher salaries.
Both American and Canadian research also concludes that students who have attended faith-based schools, compared to students in government schools, are more like to volunteer, to donate to charities and a more likely to marry and not divorce.
Trevor Cobbold refers to 30 studies to support his argument that non-government schools do not outperform government schools. Andrew J Coulson from the US out trumps Cobbold when he writes "In more than 150 statistical comparisons covering eight different educational outcomes, the private sector outperforms the public sector in the overwhelming majority of cases".
The critics, instead of attempting to downplay the performance of non-government schools, should focus on identifying the real reasons such schools do so well and then analyse what can be done to help government schools achieve similar results.