Stanines

Stanines in Educational Settings

In education, stanines are commonly used to report to teachers and parents about a student’s relative standing compared with other students in the jurisdiction at the same grade level on a particular test. Because it gives a single digit score, which is always a whole number and is always [Page 1610]positive, the general indication of relative standing is easily understood and is not likely to be confused with the child’s actual score on the test, as can be the case with other types of standard score. As a score for an individual, stanines are also commonly used to select students for educational intervention or to assess a student’s relative strengths across different tests. When tests are closely aligned with curriculum outcomes, stanines can be used to inform teachers and parents about school achievement.

Limitations of Stanines

Like any system that divides scores into a limited number of equal intervals, stanines can be imprecise, in that the actual test scores or percentile ranks of two students with the same stanine may be more different from two students with different stanine scores. As an example, two students with a stanine level of 5 may be at the 40th and 59th percentiles, respectively, whereas a student with a stanine score of 4 may be only one percentile rank score different from a student at stanine 5. The differences between two students at either end of any given stanine band will be lost information. Similarly, over time, a change in only one raw score point may move a student from one stanine to another, which may give a false impression of relative improvement. For this reason, it is sometimes recommended that a shift of two stanines, the equivalent of one standard deviation, is needed to be assured of improvement. Stanines, like other standardized scores, are also unable to give information about learning needs, specific item knowledge, mastery, or learning progress in terms of curriculum outcomes.

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