Assessing the Impact of Curricular Redesign: Student Performance in a Foundational Anatomy Course with Added Cell Biology and Histology

Abstract Body : Introduction and Objective
Beginning in 2021, Texas Tech University Health Sciences Center (TTUHSC) both significantly restructured and shortened its preclerkship curriculum and transitioned from categorical to Pass/Fail grading, all while emerging from the Covid-19 pandemic. Curriculum redesign included moving ~25 hours of cell biology/histology (CB/Histo) content from another legacy block into Clinically Oriented Anatomy (COA) to create a new Anatomy, Histology and Embryology (AHE) block without lengthening it. We sought to evaluate any change in student performance and course evaluation coincident with the multiple adjustments made to this new block. To assess student retention of key concepts, we compared student performance on both entire unit exams and numerous exam items before and after the curriculum change.

Materials and Methods
We evaluated student performance on faculty-written exams in the AHE block by comparing performance on 1) entire unit exams, 2) content-specific modules (anatomy/embryo vs CB/Histo) and 3) specific questions. The specific questions we compared had been used for the last two years of the legacy curriculum (COA) and the first two years in the new curriculum (AHE). Teaching modalities, instructors, and resources were the same for both old and new blocks and across units within blocks. As part of the end-of-block surveys on both old and new blocks, we asked students how much of time they spent on specific topics during their exam preparations as well as their level of satisfaction with the block.

Results
For AHE, the overall student performance on the first unit exam decreased significantly compared to the former COA block (2019 & 20 vs. 2021 & 22 p< 0.01), despite no change in performance for 13 anatomy and embryo questions that were used each year from 2019 to 2022. We also evaluated 10 CB/Histo questions that performed well in the legacy curriculum (85% avg. 2019 & 20) but poorly in the AHE block (60% avg. 2021 & 22). This decrease in student success on CB/Histo content was significant (p< 0.01). Student surveys indicated they spent ~91% of their time on the anatomy and embryo material and only ~9% for the CB/Histo content. Over all four years, students reported a high level of satisfaction with their educational experience.

Conclusion
The addition of CB/Histo to Unit 1 of AHE was associated with reduced overall student exam performance. The reduction in test scores was attributed solely to poor performance on CB/Histo content. Possible contributors to this result might include the added content density in the first unit, student reallocation of study time in favor of anatomy/embryology, or the shift in placement of CB/Histo compared to the legacy curriculum, where the material was presented within a fuller context of organ histology. Future iterations may include redistribution of CB/Histo content into the other units of AHE as well as emphasis on connections between micro- and gross anatomy. The impact of the contemporaneous shift to Pass/Fail grading is harder to measure but likely to be meaningful.

Significance/Implication
Curricular restructuring coupled with the transition to Pass/Fail grading within the context of other Covid-related disruptions created some unanticipated negative (student performance) and positive (student satisfaction) consequences. Future efforts to raise performance while maintaining satisfaction will require continued adjustments by block leaders.