Understanding your data

LASS results

When considering LASS 11-15 results, it is important to bear in mind that it is not one test that is being interpreted, but the performance of a student on a number of related tests.

LASS 11-15 results are analysed in relation to norms in 12-month age bands. For each individual test, a centile score less than 20 reflects significantly below average performance. This is a standard cutoff point in identifying special needs or moderate educational weaknesses and the student should be considered for intervention of some kind. Centile scores less than 5 suggest a serious difficulty. This is diagnostically significant and a strong indication that a student requires intervention. Please note that centile scores are standardised scores.


LASS 11-15 is also a profiling system, so when making interpretations of results it is important to consider the student’s overall profile. The most important aspect of a student’s overall profile is how their reasoning test score, used as an indicator of intellectual ability, compares with their scores in other modules of LASS 11-15. Any difference is referred to as a ‘discrepancy’. For example, a centile score of 30 for reading or spelling would not normally give cause for concern because it does not fall below the 20th centile threshold. But if the student in question had a centile score of 85+ on the reasoning test, that would be a significant discrepancy and would give cause for concern.

In considering a student’s profile it is important to consider strengths as well as weaknesses. Absolute strengths will appear as centile scores in the range 80+, while absolute weaknesses will appear as centile scores in the range below 20 (see Section 4.1.2 for an explanation of thresholds for interpreting absolute weaknesses). Relative strengths and weaknesses, however, are shown in terms of discrepancies between scores – usually between the Reasoning score and the other individual scores.

For further information please see Understanding LASS 11-15 and the User Manual for more information, both of which are available in the Downloads section.