Students' ability to accurately judge their knowledge is crucial for effective learning. However, students' perception of their current knowledge is often misaligned with their actual performance. The relationship between learners' perception of their performance and their actual performance on a task is defined as calibration. Previous studies have shown significant student miscalibration in an introductory biology course: students' predicted exam scores were, on average, significantly higher than their actual scores. The goal of this study was to determine whether completion of a practice test before exams would result in better performance and calibration. The hypothesis was that students who completed a practice test would perform better and be better predictors of their performance on exams than students who did not engage in practice testing. As predicted, students who voluntarily completed a practice test, on average, performed better and were more calibrated than students who did not. Importantly, however, many of the lowest-performing students continued to significantly overestimate their knowledge, predicting higher scores on the exam than they actually earned, despite feedback from practice tests. In contrast, practice testing was associated with underconfidence in high-performing students. These findings indicate that practice tests may enhance calibration for many students. However, additional interventions may be required for the lowest-performing students to become better predictors of their performance.

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Published in Journal of Microbiology & Biology Education, v. 22, no. 2.

Copyright © 2021 Osterhage

This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

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Funding Information

Research reported in this publication was supported by an institutional development award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM103436.