The degree to which an assessment accurately measures the skill, knowledge or characteristic it was designed to measure.

The degree to which the results of a standardized test are consistent and replicable.

A set of standard scores on a group test with nine bands of results. Results falling into bands 4, 5, and 6 represent average performance.

Converts the results on an assessment to a normal curve with a mean of (usually) 50 and a standard deviation of (usually) 21.06 for ease of interpretation of results. A scale with 100 equal parts.

Converts the results on an assessment to a mean of 50 and a standard deviation of 10 for ease of interpretation of results.

Converts the results on an assessment to a mean of zero and a standard deviation of 1 for ease of interpretation of results.

A derived score statistically created as a measure of a total score on a standardized test or a subtest of the test.

A derived score statistically created to convert a child’s raw score to a measure that can be used to assess the child’s mastery of a specific topic or skill.

A derived score which shows the percent of students in the standardized test’s normative group which would have fallen at or below a particular raw score.

A derived score based on adjusting a student’s raw score on a standardized test by a factor that reflects normal performance for a particular grade.