Association of the Transition to Online Examination with Grading Patterns in Medical Basic Sciences: A Single-Center Retrospective Study Before, During, and After the COVID-19 Pandemic.

BACKGROUND

The COVID-19 pandemic led to a sudden shift from in-person to online teaching and evaluation, prompting concerns about academic integrity, changes in grading practices, and potential grade inflation. This study examines temporal trends in grade distributions in medical Basic Science courses at Tehran University of Medical Sciences (TUMS) across three phases: pre-pandemic, during-pandemic, and post-pandemic.

METHODS

This retrospective study examined the academic results of Doctor of Medicine students admitted to TUMS from the summer semester of 2019 to the winter semester of 2022. Grades were categorized by the timing of the Comprehensive Basic Science Examination (CBSE) as pre-pandemic (through March 2020), during-pandemic (April 2020 to March 2022), and post-pandemic (April 2022 to March 2024), depending on whether TUMS conducted in-person or online activities. Outcome metrics were course-specific grades, cumulative Basic Science courses grade point average (GPA), and CBSE scores.

RESULTS

The GPA was available for 1510 students, and CBSE scores were available for 1,310 students. The mean GPA of Basic Science courses significantly decreased from 16.97 ± 1.38 pre-pandemic to 16.24 ± 1.49 post-pandemic (P < 0.001), indicating an overall post-pandemic decline in cumulative Basic Science performance. In contrast, CBSE scores showed a non-significant decline (129.30 ± 23.81 vs. 122.00 ± 28.95; P = 0.09). Course-level patterns were heterogeneous: several courses (Epidemiology, Medical English, Physiology, Virology) showed transient increases in top grades during the pandemic, whereas other courses (Mycology and Anatomy) showed ceiling effects, and still others (Parasitology and Microbiology) showed net declines (all P < 0.001).

CONCLUSION

The transition to virtual assessments at Tehran University of Medical Sciences was not associated with sustained, system-wide grade inflation; instead, observed grading patterns were heterogeneous and course-specific. While several lecture-style courses showed transient increases during remote assessment, other courses showed ceiling effects or net declines, and overall Basic Science GPA decreased post-pandemic. These findings support the design of targeted assessments or security improvements. However, interpretation is limited by the single-center design, missing course-level data, and small pre-pandemic subgroups in several course-specific analyses.