About Test Scores

Test scores are estimates of the attribute measured by the test. The accuracy of test scores depends on numerous factors, such as the following:

• Student's feelings about being tested
• Familiarity with standard English
• Cultural differences
• Conditions of the testing setting
• Mental or physical restrictions

Used properly, test scores are combined with other relevant information to assist with decisions about the student's needs. Scores from a single test should never be used to identify abnormal functioning, or in any way limit participation in the general educational program.

When test scores are placed on common scale, or standardized, direct comparisons can be made among them.

• For Standard Scores (SS) the average is 100, with 90 to 110 often considered the average range.
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• For Scaled Scores (ScS) the average is 10 and the average range is often from 8 to 12.

The Percentile is based on the Standard and Scaled Scores and provides an estimate of the percentage of students in your child's age range or grade in school that, if tested, would earn lower scores. The average Percentile is 50 and the average range is usually considered to be between the 25th and 75th percentile.

Ranges of Standard and Scaled Scores in this report are described using various sets of terms chosen by the author or publisher of each test. The following is an example of one such system of descriptors:

T-scores, with an average of 50 and a typical average range of 40 to 60, make up another type of standardized score. T-scores are most often used with behavior rating scales.

The behaviors most often measured by T-scores are either: 'adaptive' (for example, Social Skills), where high scores are desirable and low scores suggest need for improvement; or 'clinical', where high scores may indicate a problem needing to be addressed and lower scores are considered normal or desirable.

This table shows a sample system of descriptors that might be used for adaptive and clinical scores:

For more specific information or questions please contact one of our school psychologists.