Subscores Based on Classical Test Theory: To Report or Not to Report |
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| Authors: | Sandip Sinharay Shelby Haberman Gautam Puhan |
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| Institution: | Educational Testing Service |
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| Abstract: | There is an increasing interest in reporting subscores, both at examinee level and at aggregate levels. However, it is important to ensure reasonable subscore performance in terms of high reliability and validity to minimize incorrect instructional and remediation decisions. This article employs a statistical measure based on classical test theory that is conceptually similar to the test reliability measure and can be used to determine when subscores have any added value over total scores. The usefulness of subscores is examined both at the level of the examinees and at the level of the institutions that the examinees belong to. The suggested approach is applied to two data sets from a basic skills test. The results provide little support in favor of reporting subscores for either examinees or institutions for the tests studied here. |
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| Keywords: | institutional-level subscore mean squared error reliability |
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