Published by The Australian, Wednesday 30 May

Forget what you may have heard recently: ATAR is not on its way out. The Australian Tertiary Admission Rank is still a used and useful tool for universities and for school students considering higher education.

For school-leavers, ATAR remains the key to entering most university courses.

In 2016, about three-quarters of school-leavers were admitted to university based on their ATAR. Some lower percentages have been reported recently, but they are mainly due to older students entering a new course based on their previous post-secondary education. Most of whom were originally admitted to university based on their ATAR.

For most school-leavers, ATAR dictates not only whether they get into university but also the array of course options available to them. The higher your ATAR, the more likely you are to receive an offer to undertake your first-preference university course.

Universities use ATAR because it is a fair and efficient way of allocating student places. ATAR uses information collected by the school system, avoiding the additional stresses and costs of some other admissions systems, which require aspiring students to sit another exam.

But ATAR is not just about reducing stress and cost, it’s also a good indicator of how well students will do at university.

Students with a lower ATAR are more likely to drop out of university. A quarter of students whose ATAR was below 60 and who received a university offer either rejected it, or accepted but did not stay until the so-called census date — when students become liable for their university fees.

In contrast, only 6 per cent of students with an ATAR of 90 or higher dropped out of their course before the census date.

And students with a higher ATAR are more likely to do well at university. Over the past decade, more than one in 10 students with an ATAR lower than 60 failed all their subjects in the first semester. The failure rate for students with an ATAR of 90 or more was less than a fifth of that.

Yet because having a low ATAR is often associated with other factors that could affect how well students do at university, such as socioeconomic status, their performance could have been driven by the other factors.

Recently published Grattan Institute research shows that even after accounting for personal characteristics, study choices and the university attended, lower ATARs are still associated with a higher risk of dropping out.

Students with ATARs below 60 are twice as likely not to finish their degree within eight years as otherwise similar students with ATARs of 90 or above.

Of course, ATAR is not perfect. It ranks students using their aggregate high-school study scores.

Because most people get school results near the average, study scores follow a bell shape, with many students in the middle and fewer getting very high or very low scores.

Converting study scores to ATAR requires “stretching” the bell. As a consequence, ATAR ­exaggerates differences between students in the middle and understates differences for those at either end.

For example, the study score difference between an ATAR of 90 and 99.95 is about five times greater than the difference between an ATAR of 45 and 55. So ATAR is less useful for universities trying to choose between applicants with lower ATARs, who may have only small differences in academic ability.

Universities should supplement ATAR with other indicators when choosing between lower-ATAR students. For example, more universities could make passing school maths a prerequisite for entry to IT and engineering courses, which have high fail rates.

Low-ATAR university students with a sub-bachelor or vocational qualification have better prospects of completing their degree. More universities could use this as a criterion for admission.

No single criterion is perfect for all students. Universities should use the most relevant academic results to select their students — and for most school-leavers that is ATAR.

The lessons for school students are clear: ATAR is still the most common way for school-leavers to get into their desired university course. The higher a student’s ATAR, the better their prospects of success at university.

If you aspire to university, you should work hard at school to achieve your best ATAR.