NAPLAN certainly gets people talking. Just about everyone I meet has heard of NAPLAN and nearly all of them have an opinion on it. That people know about it is a good thing, and that people have views on it is also a good thing. Both are healthy signs.

Before exploring different perspectives on NAPLAN it is worth taking a moment to consider a few of the alarming statistics associated with illiteracy:

• Illiteracy costs the global economy more than one trillion US dollars each year.
• More than 796 million people in the world cannot read and write.
• Illiterate people earn 30–42% less than their literate counterparts.
• A child born to a mother who can read is 50% more likely to survive past age five.
• Estimates, in various nations, show that 60–80% of prisoners have reading and writing skills below basic levels.
• Up to 85% of juvenile delinquents are functionally illiterate.

So it is vital to know how our young people are developing in their literacy and numeracy skills. The critical importance of literacy in particular is underscored by the fact that NAPLAN tests include assessments in reading, writing, grammar and punctuation, and spelling, which are all key components of literacy. Numeracy is tested at year 3, and the development of students' knowledge and skill is measured by further numeracy assessments at Years 7 and 9.

If literacy and numeracy are clearly so crucial to a young person's success at school, why is there so much debate about NAPLAN? I think the answer lies in the different views people have on how best to measure literacy and numeracy. In this article I want to focus on explaining some of the aspects of NAPLAN that do not feature prominently in the public debate, and also address some of the misconceptions about the program and the tests themselves. My purpose in doing so is to demonstrate that, when understood in context, NAPLAN has much to offer that is positive and of real benefit to students, schools and parents. I hope this article helps to inform the wider public debate over the NAPLAN tests.

The NAPLAN program was introduced in 2008, after agreement by all ministers, to enable fair and informed comparisons of performance between states and territories, and to measure national performance in literacy and numeracy annually and over time. NAPLAN replaced state and territory tests, some of which had been administered for many years. This basic purpose of NAPLAN seems at times to get lost in the debate.

NAPLAN tests are developed by experts. They are experts because they specialise in test development, they apply rigorous processes and principles to item development and test construction, and they comply with strict specifications. It is worth noting that almost invariably test developers have themselves been teachers. The process for reviewing test items includes a very large panel of people from across Australia, most of whom have also been teachers. These experts know about young people and their learning, and what they can and should know at different levels. The test specifications have been developed against state and territory curriculums and will eventually be based on the common Australian Curriculum. So students are not confronting test content that they have not been taught.

How do we confirm this? Every item used in a NAPLAN test has been field trialled with a large, scientific sample of students in the relevant year levels. The item performance statistics must meet rigorous technical standards if they are to find their way into the tests. As NAPLAN is a 'range' test, it measures student performance across a broad spectrum of ability typically evident in a large population like the one doing the tests – over one million students. In the process of test development, close attention is also paid to the cultural appropriateness of items for the different ethnic groups and our indigenous students. This 'screening' of items for cultural appropriateness is undertaken conscientiously and sensitively. Test developers don't always get it right and at times some items have been subjected to legitimate criticism in this respect. The ultimate test of the quality and suitability of the tests is the analysis of the student performance data they produce. Every year that analysis confirms that the tests have worked successfully.


The diagnostic function of NAPLAN data

So the next key question is: how is test data useful to schools, parents and students? This is where the 'diagnostic' dimension to the tests comes to the fore, although once again not without some misconceptions and mixed understandings. A medical diagnostic test is performed to aid in the diagnosis or detection of disease. Diagnostic testing is also an important tool for educators who want to know where their students are academically in order to bring those students to where they need to be. If you want your students to move forward, you need to identify where they have started; diagnostic testing is the way to do this. These diagnostic assessments happen routinely in many classrooms, although some teachers may need further training in how to develop such tests, and how to understand and analyse the data they produce to maximise the positive impact on teaching and learning.

NAPLAN data is diagnostic to the extent that it provides detailed item-by-item information about each student's performance. The data can also be aggregated up to a group, class, year level and school level where it informs different and important decisions. NAPLAN data at these different levels of aggregation provides an evidence-base to inform teaching programs, and the use of valuable resources.

One concern about NAPLAN is the time that elapses between students sitting the tests and receiving the performance data: a delay of approximately 17 weeks. Authorities are considering how this time lag might be reduced. Online assessment is the most promising way to speed up the return of NAPLAN results to schools, teachers, students and parents. Online assessment also has the significant advantage of allowing a 'branched' or 'tailored' test design in an online mode: this enriches the data for each student by making the tests more targeted.

Parents consistently express their support for the information the NAPLAN data provides on the performance and progress of their sons and daughters. Parents want honest and reliable advice that is also objective. What needs to be continually reinforced in any messaging to schools, teachers and parents is that test drills or excessive practicing are counter-productive and detrimental to the school's program, and quite unnecessary. Students need to be reassured often that they need only do their best once having become familiar with what the tests look like and what they are being asked to do. It is all about keeping NAPLAN in context.

In summary then, NAPLAN is a very high quality assessment and the tests do what they are intended to do. The data produced by the program is valuable when used effectively and thoughtfully. It is better to make decisions on the basis of evidence wherever possible. And finally, NAPLAN data is just one source of information alongside everything else schools and parents know about the skills, knowledge and talents of our young people.