NAPLAN's transition from pen-and-paper testing to online testing promises to provide better results and "a faster turnaround of information"
"The results will be more precise and give a lot more insight into your child's achievement."
But in the first of a three-year rollout, some say it's the online test that causing a delay in the release of the results.
The Australian Education Union says the setback has been prompted by questions over whether the data is credible.
The Union's President, Correna Haythorpe, believes the results of online tests cannot be mapped fairly against the pen-to-paper exams.
"We were expecting to see the delivery of the NAPLAN online report today, however we now understand there are serious concerns with the validitly of the data and we are gravely concerned with what's been happening."
Of the one million students in years three, five, seven and nine assessed this year, around 200,000 took the standardised tests online.
Ms Haythorpe says the Australian Curriculum, Assessment and Reporting Authority, ACARA, was due to publish a summary of the preliminary NAPLAN results on Wednesday 8th August 2018.
But reports suggest that after seeing their students' test scores, some state education principals raised concerns about whether data between the new online and traditional written tests can be compared.
NAPLAN Online uses what it calls a 'tailored test design' where, as students’ progress through the test, the questions adjust to match their abilities.
"Tailored testing automatically adapts to a student's performance and allows each student to demonstrate their knowledge with questions that match their test performance."
For example, a child who is struggling will be offered questions they are more likely to be able to answer, while students who take the paper test all receive the same questions, regardless of their achievement level.
ACARA insists data analysts and measurement advisory experts have told them the data are valid and comparable.
In a statement, ACARA CEO Robert Randall says despite reports of a delay, the NAPLAN results are "on track to be released soon," adding that "ACARA expects this will be within coming days."
But Correna Haythorpe is not convinced, and says there are widespread concerns with the online component of the test.
"We've had broad consultations with our members across the country about the delivery of NAPLAN online and they have expressed their concerns with the system's readiness, in regards to the infrastructure of our schools around ICT, around internet coverage. But also the significant inequities that are faced in our schools because of resource shortages, and many of our students being educated in disadvantaged communities, actually not having access to the ICT and technology that they need to take a test online."
