Putting post-decision wagering to the test: a measure of self-perceived knowledge in basic sciences?

Students learn more effectively when they know what they do not know. Gaining insight into students' metacognitive awareness is needed as misalignment between actual and self-perceived knowledge impedes their learning process. The optimal method of measuring self-perceived knowledge is still under debate. In this study, we evaluate the use of psychology-derived post-decision wagering for mapping students self-perceived knowledge. Students (n = 71) performed a pre-test on medical physiology, followed by a teacher-moderated discussion and a post-test with isomorph questions. Half of the students rated their self-perceived knowledge on each question using post-decision wagering, i.aEuroe. betting 1-5 points on the correctness of their answer, whereas the other half used a 5-point Likert scale to rate their confidence. Self-perceived knowledge scores were higher for post-decision wagering (pre: 3.75 +/- 0.14, post: 4.60 +/- 0.07) compared with Likert scales (pre: 3.13 +/- 0.08, post: 3.92 +/- 0.08) despite similar actual knowledge scores. Furthermore, Likert ratings showed a near-normal distribution, whereas wagers were placed preferentially using the outer ends of the scale. Correlations between mean actual and self-perceived knowledge scores were low in both groups. On average, 8.5% of responses were classified as misconceptions, defined as highly confident incorrect answers. Despite the presumed reliability of post-decision wagering, our findings suggest that we should adhere to the use of Likert scales as a balanced measure for self-perceived knowledge in medical education. Moreover, the prevalence of misconceptions did not alter after instruction, indicating a need for instructional designs that enhance students' conceptual understanding in basic sciences.