Study population and study design
This study was designed to assess the academic achievement and attitudes of second-year medical students toward teaching methods used in cardiovascular physiology course topics, retrospectively for the pre-COVID-19 year and prospectively for the COVID-19 year. All students enrolled in the Cardiovascular System I course at the Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand were included in the study unless they withdrew. The Cardiovascular System I is the course taught in the second year of the medical curriculum comprising 16 lecture subjects (24.5 h) and 17 non-lectured subjects (44 h) covering anatomy, histology, biochemistry, physiology and the basic hematology. Of all course topics, 10 topics are relevant to Cardiovascular Physiology, listed in Table 1. Course details have been described previously . In this study, we sought to analyze only the topics related to cardiovascular physiology since they were taught only by lectures, which were the object of this study, and represented the majority of the knowledge contents covered by the course.
Regarding the cardiovascular physiology subjects presented in Table 1, some subjects were taught by the same teachers while some subjects were taught by different teachers between these two academic years. Nevertheless, all teachers were content experts in the respective cardiovascular topics. The topics covered in this course and the length of instruction for each topic were similar for both years. In the pre-COVID-19 year, all lecture topics were taught in a large amphitheater through traditional lectures. Due to the COVID-19 pandemic and implemented physical distancing policies, all topics have been moved to asynchronous online lectures during the COVID-19 year. Asynchronous online lectures were newly recorded by speakers who taught these topics. Most lecturers used computer software, such as Microsoft PowerPoint and OBS Studio, to record lecture slides along with their narrations. A recorded lecture covered one topic and was typically 45-60 minutes long. The online lectures, aka e-lectures, have been uploaded to the faculty’s available online platforms (the MDCU E-learning website, available at http://e-learning.md.chula.ac. th) and the university (the myCourseVille learning management system, available at https://www.mycourseville.com/). After the lecture sessions, an interactive question-and-answer (Q&A) session was conducted in the amphitheater in the pre-COVID-19 year and via an online platform in the COVID-19 year to answer questions from students and chat interactively. the obscure points raised by the pupils. It should be noted that the Q&A session was a non-compulsory session.
Measure of academic success
The academic results of the students were assessed by the summative examination which took place approximately 6 weeks after the end of the course. During the two academic years, the summative examinations of these courses were held on site in the examination room. With the epidemic prevention measures in the COVID-19 year, the exam was held the same as the pre-COVID-19 year. The summative exam consisted of 5-option Single Best Answer (SBA) questions, which is 112 questions for the pre-COVID-19 year and 108 questions for the COVID-19 year. More specifically, 64 questions out of 112 and 62 questions out of 108 aimed directly at assessing the knowledge of cardiovascular physiology taught in class. Student summative marks were analyzed and reported as a percentage of total marks. It should be noted that the remaining questions were excluded as they were not relevant to the objectives of our study, i.e. they were used to assess knowledge of anatomy, histology, biochemistry or cardiovascular physiology taught by other teaching methods such as live online lecture, small group discussion and asynchronous lab demonstration.
To ensure equivalence in the summative assessment used over these two years, five physicians were asked to rate the relevance and difficulty of all exam items using the modified Ebel method, resulting in the minimum pass level for each item. . Items from the two academic years were grouped and randomly ordered so that assessors would not know which year each item belonged to. All evaluators independently determined the level of relevance (important/essential, acceptable or questionable/additional) and difficulty (easy, moderate or difficult) of each item. The expected percentage of correct answers was ranked in the Relevance Matrix by Difficulty 3×3 [18,19,20]. Percent correct values and discrimination indices of all items were also analyzed. . Items with negative discrimination indices, ie one item from each year, were excluded. Test reliability coefficients were calculated using the Kuder-Richardson formula 20 (KR-20) . KR-20 value between 0.70 and 0.90 has been accepted as a reliable assessment .
School Achievement Subgroup Analysis
To determine whether a difference in teachers/lecturers influences academic achievement, we performed a subgroup analysis by classifying each lecture topic into the topic taught by the same teachers (topics 4 through 8 and 10 in Table 1). ) or in the subject taught by different teachers (subjects 1 to 3 and 9 in Table 1). Then, a difference in academic achievement between university years was analyzed using you test.
Measurement of student satisfaction
To assess student attitudes, course evaluation was conducted at the end of the course through an online questionnaire, in which all items had been created, reviewed and approved by the course committee, at the Google Forms help (the free Google Docs editors on the web). Students could complete the questionnaire anonymously and voluntarily. Students rated the quality of each lecture with a 5-point rating scale as follows: 5, excellent; 4, good; 3, medium; 2, fair; and 1, poor. During the COVID-19 year, 8 statements from Table 2 were included to assess student agreement (strongly agree, agree, unsure, disagree, or strongly disagree) with asynchronous online courses and the Q&A session. Finally, an open-ended question was included to specifically probe student attitudes toward online teaching. For the open question, student comments were categorized into positive and negative comments by consensus of 2 independent investigators.
The questionnaire had been carefully reviewed and approved by the Cardiovascular System I course committee and used to assess student satisfaction for several years, with the exception of the 8 newly added statements in Table 2. In addition, all questionnaire items were assessed for content validity and reliability . Content validity was determined using the item-objective congruence index by 3 independent experts. Reliability was determined by Cronbach’s alpha. Our analyzes showed that the item-objective congruence indices of the 8 newly added statements and the satisfaction questions were 0.79 and 1.00, respectively. Cronbach’s alpha was 0.87 for the 8 new statements and 0.75 for the satisfaction questions representing acceptable quality of the questionnaire.
Subgroup analysis of student satisfaction
To determine whether a difference in teachers influences student satisfaction, we also performed a subgroup analysis on subjects taught by the same or different teachers (Table 1). Then, a difference in student satisfaction between academic years was analyzed using you test.
Categorical data, i.e. the sex of the participants, were demonstrated in frequency and percentage and analyzed by the chi-square test. Unless otherwise stated, continuous data have been presented as the mean, standard deviation (SD), and 95% confidence interval (95% CI). To compare the difference between the groups, the continuous data including the satisfactory level and the subgroup analyzes were analyzed by you test. Statistical analysis was performed by Microsoft Excel (version 16.0.13530.20368) and GraphPad Prism (version 9.0.0). A p a value