Purpose
Developing clinical reasoning across the medical curriculum requires valid, reliable, and feasible assessment tools. However, few validated tools are available for the convenient and efficient quantification of clinical reasoning. Thus, this study aimed to create a shorter version of the Diagnostic Thinking Inventory (DTI) and validate it in the Korean medical education context (DTI-SK).
Methods
The DTI-SK was constructed using content validity and a translation and back-translation process. It comprises two subcategories and 14 items. Its validity and reliability were explored using exploratory and confirmatory factor analyses, mean comparisons of four medical student groups (med 1 to med 4), and internal consistency using Cronbach’s α. Two hundred medical students were invited to participate through email, and the survey was administered for 2 weeks.
Results
Data from 136 students were analyzed. Exploratory factor analysis revealed two factors with eigenvalues greater than 1.0 and they together explained 54.65% of the variance. Confirmatory factor analysis demonstrated that the model had acceptable level of fit and convergent validity. Discriminant validity was confirmed using heterotrait-monotrait criterion. Group comparisons demonstrated that the med 4 students showed significantly higher scores than the med 1 and 2 students. The inventory exhibited strong internal consistency for all items (Cronbach’s α=0.906).
Conclusion
The findings indicated that the DTI-SK is a reliable and valid tool for measuring medical students’ clinical reasoning in the context of Korean medical education.

Purpose
The development of students’ clinical reasoning skills should be a consideration in the design of instruction and evaluation in medical education. In response to the coronavirus disease 2019 (COVID-19) pandemic, several changes in the medical curriculum have been implemented in promoting clinical reasoning. This study aims to explore medical students’ perceptions and experiences with the clinical reasoning curriculum during the COVID-19 pandemic and determine their skills development.
Methods
The study used a mixed-method design with a concurrent approach. A cross-sectional study was conducted to compare and examine the relationship between the outcomes of the structured oral examination (SOE) and the Diagnostic Thinking Inventory (DTI). Then, the qualitative method was used. A focus group discussion using a semi-structured interview guide with open-ended questions was conducted, then the verbatim transcript was subjected to thematic analysis.
Results
There is an increase in SOE and DTI scores between second-year to fourth-year students. The diagnostic thinking domains and SOE are significantly correlated (r=0.302, 0.313, and 0.241 with p<0.05). The three primary themes from the qualitative analysis are perceptions regarding clinical reasoning, clinical reasoning activities, and the learning component.
Conclusion
Even if students are still studying throughout the COVID-19 pandemic, their clinical reasoning skills can improve. The clinical reasoning and diagnostic thinking skills of medical students increase as the length of the school year increases. Online case-based learning and assessment support the development of clinical reasoning skills. The skills are supported in their development by positive attitudes toward faculty, peers, case type, and prior knowledge.