Standardised Scores: About
Updated
You can use the Standardised Scores mark scheme to record standardised test results from your test provider(s). Standardised scores are more easily comparable over time and between subjects than raw scores and other test data.
Scaled Scores, including SAT Scaled Scores, are calculated differently from Standardised Scores and should be recorded using a different mark scheme. Please refer to SAT Scaled Scores and The difference between standardised and scaled scores for more information.
Evaluation of Standardised Scores
Commonly we see pupils defined as below, average and above using the 85 and 115 thresholds (i.e. one standard deviation from the mean) but this does not provide a great deal of refinement and means that the average band contains 68% of pupils nationally. It therefore makes sense to further subdivide the data. Our best option for comparison with Scaled Scores is to use percentiles because both sets of scores have common, percentile values. The DfE Statistics website provides detailed tables that show the distribution of scaled scores and these give us the percentile value of each scale point. To better understand the relationship between percentile rank and standardised score, this table is an excellent resource. Once we have the percentile values of both scaled and standardised scores, we can convert one to the other; and this blog post, which includes a lookup table for 2019 KS2 scaled scores, describes the method in more detail.
By default, Insight evaluates - colour codes - Standardised Scores based on the percentile relationship outlined above, using the following thresholds. These can be customised for your setup.
Standardised Score range | Description | Insight Evaluation |
<70 | Well below average | Red |
70-84 | Below average | Red |
85-94 | Low average | Amber |
95-105 | Average | Green |
106-115 | High average | Green |
>115 | Above average | Blue |
Note that on most of Insight's cohort and analysis reports, standardised scores will be grouped according to their evaluation, rather than the score ranges above. For a more detailed breakdown by range, you can use the Progress Matrix report or the Settings on the Overviews - Attainment report (Change "Compare" to "Detailed Evaluation").
More Information on Standardised Scores
'Raw' test scores are often standardised in such a way that:
- The average score is 100, making it easy to compare a pupil's performance against the average performance or against the same pupil's performance in other tests. This also means that standardised scores for groups (such as classes or schools) can be meaningfully averaged and compared. This means, for example, that you can compare the performance of your school against national averages, or of your boys against your girls across your whole school.
- The spread of scores (the standard deviation) is -/+ 15, meaning that roughly two thirds of pupils in the national sample (not within each school) will achieve a score between 85 and 115. Scores outside this range are usually considered exception: roughly 95% of pupils achieve a score between 70 and 130, and roughly 99% achieve a score between 60 and 140.
- Test scores are usually also adjusted so that the resulting standardised scores make allowances for the differences in pupils' ages (sometimes called an Age Standardised Score, or Standard Age Score)
Percentile Ranks
On request (contact support) Insight can automatically calculate a pupil's Percentile Rank based on their Standardised Score, and show this in brackets, eg: 101 (53%)
This is a useful way to see where a pupil sits compared to the average. For example, a pupil who has a Percentile Rank of 50% performed at the same level or better than 50% of the sample group.
