Understanding your data

Any test score is only an estimate of the student’s ability, based on their performance on a
particular day. Performance on any test can be affected by several factors. The Rapid report
provides confidence bands, which give an indication of the range within which a student’s score
lies. The dot on each subtest row within the table represents the student’s SAS and the horizontal
line represents the 90% confidence band. The shaded area shows the average score range. 90%
confidence bands are a very high-level estimate; if the test were taken again, we would expect
the score to fall within this range 90% of the time.

The Rapid report identifies SAS scores of 88–94 as being ‘Slightly below average’, SAS scores
of 75–87 as ‘Below average’ and SAS scores below 75 as being ‘Very low’. As such, action is
recommended where SAS scores are in any of these ranges and the Rapid report will refer the
tester to the Indications for Action table on the GL Ready Support website (www.glreadysupport.
com), where appropriate. The GL Ready Support website can be accessed via the ‘Help’ button
on the GL Ready website.

The results of the three subtests are combined by the program to arrive at an overall probability
of dyslexia, which is also shown on the reports screen. This is achieved by means of an algorithmic
expert system derived from research data. The overall probability cannot be worked out until the
student has completed all three subtests.

The expert system gives an overall estimate of the probability of dyslexia in one of the following

  • High probability of dyslexia (greater than 90% chance)
  • Moderate probability of dyslexia (greater than 75% chance)
  • Low probability of dyslexia (less than 10% chance)


For more information consult the User Manual in the Downloads section.