About the subtests
LASS 8–11 comprises three attainment subtests (Single word reading, Sentence reading and Spelling), two ability subtests (Verbal reasoning and Non-verbal reasoning) and four diagnostic subtests (Mobile phone, Sea creatures, Funny words and Word chopping). An outline of each subtest is given in Table 1. Seven of the nine subtests are adaptive, i.e. the items delivered are based on the performance of the student (see below). The remaining two subtests (Sea creatures and Mobile phone) are progressive in format, i.e. they utilise a graded series of items of increasing difficulty, together with a discontinuation algorithm whereby the test will automatically cease once the student’s ability level has been exceeded beyond reasonable statistical error.
For each subtest, instructions are spoken by the computer, and practice items are given to familiarise the student with the subtest requirements. When the student has completed the practice items, the test phase begins. The program automatically discontinues the subtest when the student’s ability level has been exceeded.
Table 1. The LASS 8–11 subtests
The term ‘adaptive testing’ refers to any technique that modifies the nature of the test in response to the performance of the test-taker. Paper-based tests are static instruments, fixed in their item content, item order, and duration. By contrast, digitised assessments can be dynamic. Since the computer can score performance at the same time as item presentation, it can modify the test accordingly, tailoring it to the capabilities of the individual taking the test much more effectively.
Conventional tests can be very crude instruments in which, much of the time, the individual’s abilities are not being assessed with great precision because the items are either too difficult or too easy. In an adaptive test the individual can be moved swiftly to that zone of the test that will most efficiently discriminate their capabilities, thus making the assessment shorter, more reliable, more efficient, and often more acceptable to the person being tested. Olsen (1990) compared paper-based and computer-administered school achievement and assessment tests with computerised adaptive tests. The computer-based non-adaptive version took 50–75% of the time taken to administer the conventional version, while the testing time for the adaptive version was only 25% of the time taken for the paper-based version. This finding is further supported by research by Carson, Gillon and Boustead (2011) and Senel and Kutlu (2018).
In the adaptive subtests in LASS 8–11, the program first gives the student a series of ‘probe’ items to determine the range of optimal item sensitivity for that student. These are followed by a series of test items starting in the range of optimal item sensitivity and increasing in difficulty until the student’s current attainment or ability level has been exceeded beyond reasonable statistical error, whereupon the test ceases. The program incorporates a facility to regress to easier items should it transpire that, by chance, the result of the probe items has overestimated the pupil’s approximate ability or current attainment level.