Child Assessment & Testing - Test Descriptions and Development

At CPAC, where possible, we use child psychometric instruments with Australian norms. To better understand how tests differ based on their normative groups and why Australian norms are important to interpret scores, please read the following brief description on test development and score interpretation.

At the core of their development, psychological tests are standardised by using groups of people as norms, against which individual performances are later compared to. The composition of groups varies, based on the purpose of the test. For example, the standardisation process of tests measuring children's intellectual ability (IQ) involves administering the tests to large groups of children in different age groups. Six year olds, 7 year olds, 8 year olds and so on. Determining an individual child's performance is based on comparing his or her scores to the average performance of children who comprised the original standardisation sample. The closer the characteristics and environmental context of children in the standardisation sample to an individual child's characteristics and environmental context, the more realistically the scores will represent his or her abilities.

IQ and achievement scores are calculated by comparing an individual child's performance to the average performance of the standardisation samples. Scores derived through this method are best treated as estimates of functioning at the time of test taking. Apart from the child's true abilities, test scores are influenced by a number of other factors, such as fatigue, interest, test anxiety and characteristics of the examiner. Reporting of test scores include the careful analysis and inclusion of these factors.

For example, when conditions are optimal and a meaningful interpretation of an intelligence test is possible, the report will contain two distinct interpretative categories, an IQ range and a percentile rank. Both categories are represented in ranges, rather than in concrete scores. While concrete scores are calculated, placing the child's performance within a range is more accurate and representative of his or her abilities. Wechsler classifications are as follows: