Longitudinal Assessment of Critical Thinking Skills Across a Dental Curriculum.

Critical thinking and problem-solving are two of the most frequently desired goals for dental student learning, but greater understanding is needed of how students' critical thinking skills develop from the beginning to the end of the curriculum. The aim of this study was to use students' performance on critical thinking assessments at five time points from the first to the fourth years to longitudinally assess their critical thinking development across the curriculum. In 2014-16, the performance of students in two successive graduating classes at one U.S. dental school was collected from five assignments designed to, among other things, assess critical thinking. Those assignments ranged from a case study in the Cariology I course in fall of the first year to an OSCE completed before graduation. Students were divided into four quartiles from lowest- to highest-achieving based on the first (baseline) assessment, and those quartiles were tracked to determine each student's progress over the four years. The results showed that, for both cohorts, students who ranked in the top quartile remained in the top of the class for all subsequent assessments. Also in both cohorts, the students who had the lowest scores on the initial assessment of critical thinking skills showed statistically significant improvements over time, increasing their scores by 9.4% (cohort 1, p<0.001) and 4.6% (cohort 2, p=0.003) in each consecutive assessment. These results suggest that implementing critical thinking assessments early in the curriculum can assist in predicting students' future performance on critical thinking assessments. Furthermore, a dental curriculum intentionally designed to promote critical thinking capacities can help students improve these skills over time, whatever their level at the beginning.