The release of new Naplan results on My School may be delayed unless a review of the controversial website satisfies state education ministers that it provides “valid” data.

A communique published after Friday’s education council meeting in Adelaide stated the individual school data would not be available until at least the end of December while the states awaited the results of a review into Naplan and My School data.

The wording of the communique – which also revealed that an independent technical review of Naplan online had been commissioned – suggested ministers had decided to hold off on releasing the results amid concerns about the comparability between online and written versions of the test.

The decision does not constitute a delay in the release of the data, which is usually not published until March. But Guardian Australia understands at least some state ministers are preparing to push back against publishing the results if a review of My School finds issues with the way Naplan data is presented.

The review, commissioned in June, is assessing whether My School provides “valid, reliable and contextualised” information and ensures reporting balances “the community’s right to know with the need to avoid the misinterpretation or misuse of the information”.

It was described by the former federal education minister Simon Birmingham at the time as “narrow” in scope, despite a push from the Australian Capital Territory, Victoria and Queensland for a more wide-ranging look at the testing regime. It is due to report its interim findings by December, with the full report expected sometime around March.

Last month state education department heads held emergency meetings over whether the results could be released at all because of difficulties comparing test scores from students who sat the test online and those who did the written version.

Victoria’s education minister, James Merlino, accused the Australian Curriculum, Assessment and Reporting Authority of botching the rollout of the test after months of reassurances.

When interim Naplan scores were finally released, they revealed that students who completed the test online had received noticeably better scores in some parts of the test than those who used paper and pencil.

This year the ACT’s education minister, Yvette Berry, said Naplan had become a “trigger for stress, anxiety and depression among young people fearful of letting someone down, as opposed to a constructive tool for learning”.

Last month Guardian Australia revealed that Berry had tried to include the issue of Naplan online data comparability into the review but was knocked back.

Friday’s ministers’ meeting in Adelaide was the first since Dan Tehan took over from Birmingham as the federal minister.

The communique said the states had given in-principle agreement to progressing the national school reform agreement, “subject to negotiations on bilateral agreements, including appropriate recognition of state and territory education funding”.

The agreement is the result of David Gonski’s review of education in Australia. The review was intended to dictate the school way funding should be directed.

While state ministers have accepted its broad thrust, some have indicated they will push for a renegotiated funding deal.

Guardian Australia understands that in Friday’s meeting some state ministers raised concerns about how the mooted deal with the Catholic education sector would impact on the overall agreement.

Under the interim funding deal agreed last year, the federal government was to contribute 80% of the school resourcing standard for private schools while the states would deliver the other 20%.

But after sustained pressure from the Catholic sector the federal government is in negotiations which are likely to lead to more funding being pumped into the sector.