Implementing a Three-Phase Four-Dimensional Blended Learning Model in Obstetrics and Gynecology Clinical Training: A Quasi-Experimental Study

Introduction: A significant challenge in obstetrics and gynecology (OB/GYN) training is effective translation of theoretical knowledge into clinical competence. To address this gap, we developed and evaluated a structured “Three-Phase Four-Dimensional” (3P4D) blended learning model to enhance clinical skill acquisition among medical students during their obstetrics and gynecology clerkship.Methods: A quasi-experimental design was adopted, as it allowed for rigorous comparison of educational interventions while accommodating the practical constraints of clinical rotationscheduling in a real-world teaching hospital. A total of 126 fifth-year clinical medical students undertaking their obstetrics and gynecology clerkship were enrolled. To ensure strict group size equality, we randomly assigned participants using block randomization with a fixed block size of 6. Within each block, a predetermined allocation ratio of 2:2:2 to the three groups was applied and randomly permuted via a computer-generated sequence, guaranteeing a final distribution of exactly 42 students per group: traditional lecture-based learning (LBL), online-intensive learning (OL), and the novel online–offline blended learning (OBL) group implementing the full 3P4D model. Outcome measures included Objective Structured Clinical Examination (OSCE), knowledge-based tests, procedural skill assessments, and a self-developed satisfaction questionnaire withestablished validity (content validity index>0.80; construct validity confirmed through exploratory factor analysis). Data were analyzed using IBM SPSS Statistics for Windows, Version 25.0. Intergroup comparisons were performed using one-way ANOVA; where significant differences were detected, post-hoc pairwise comparisons were conducted using the Least Significant Difference (LSD) test.Results: The OBL group demonstrated significantly higher scores in OSCE (89.5±4.2 vs. 80.3±4.8 vs. 76.8±5.1, P<0.001), skill operation (90.2±4.0 vs. 81.0±5.5 vs. 78.5±6.0, P<0.001), and learner satisfaction (4.6±0.5 vs. 3.8±0.7 vs. 3.5±0.8, P<0.001) compared to OL and LBL groups, respectively. Knowledge scores showed no significant differences among the groups.Conclusion: The 3P4D blended learning model effectively enhanced clinical skill acquisition and competency transformation among medical students during their OB/GYN clerkship, bridging the gap between theoretical knowledge and clinical practice.