Applying borderline methods for setting standards in objective structured clinical examination: the first case in undergraduate medical program in Vietnam

Many medical schools in Vietnam have frequently used the arbitrary 50% score of the checklist as passing scores in objective structured clinical examination (OSCE). As part of competency-based education, we apply the borderline methods in this study to determine OSCE passing scores and to demonstrate whether cut-off scores of borderline methods significantly differ from the arbitrary 50% score. This descriptive study applied the borderline group method (BGM) and borderline regression method (BRM) to determine OSCE passing scores. Our OSCE exam consisted of five stations and was administered to 406 second-year medical students (MS2) in 2023. At each station, one examiner rated both a checklist score and a global score. The Wilcoxon test was used to compare passing scores between the 50% score, mean of BGM, median of BGM, and BRM. Passing scores derived from the median of BGM and BRM across the five stations ranged from 69.6% to 88% and 69.3% to 86.3%, respectively. All passing scores based on the mean or median of BGM and BRM were significantly higher than the 50% score (p<0.05) using Wilcoxon test. No significant differences in passing scores were found between the mean or median of BGM and BRM (p=0.416 and p=0.799). Passing scores determined by borderline methods were significantly higher than the arbitrary 50% score. Borderline methods can be used as appropriate standard-setting methods for OSCE in MS2 and may be considered for future application to OSCEs for MS3 to MS6 at our university.