Design
This study used a quasi-experimental study design with pretest and posttest assessments undertaken immediately before the intervention and 1 school year after the intervention, respectively, to examine the effects of blended and offline case-centered learning for undergraduate nursing students. The study was conducted between September 2018 and July 2019.
Samples and setting
It takes 4 years to complete a Bachelor of Nursing in China. Students received nine years of compulsory education and three years of senior school, then they have an access to bachelor nursing college after college entrance examination. The main features of undergraduate nursing curricula in Fujian Medical University are shown in an additional file [Additional file 1: Table S1]. The study population comprised second-year undergraduate nursing students with the average age of (19.95±0.81) starting the Medical Nursing course in the fourth semester at the Nursing School of Fujian Medical University (Fuzhou, China), with no sampling. The Medical Nursing course was conducted for 1 academic year, in the fourth and fifth semesters, and it involved 144 teaching hours and 8 credits, which is the highest number of credits of all undergraduate nursing courses.
The students were randomly assigned by Zhengfang software (Zhengfang Corp., West Lake District, Hangzhou, China) to two classes (classes 1 and 2) upon entry to the university, with 164 and 131 students in class 1 and 2, respectively. Thus, randomization in this study occurred at the class level. An administrator employed by the university, who had no information regarding the recruitment or data collection, conducted the random allocation. Two labels (numbered 1 and 2) were placed in opaque envelopes, and the administrator then requested that the Medical Nursing teacher to selected one envelope at random. If “number 1” was picked, class 1 was to be the experimental group; otherwise, class 2 was to be the experimental group. As “number 1” was selected, there were 164 students (141 females and 23 males) in the experimental group and 131 (119 females and 12 males) in the control group at the beginning of the study. The experimental group involved eight groups, while the control group involved seven groups, with each group consisting of approximately 20 students.
Intervention
Teaching arrangements
The learning objectives of the Medical Nursing course are: (i) to master the theoretical knowledge of this course; (ii) to improve students’ capability regarding holistic nursing; (iii) to equip students with the ability to analyze and solve problems as well as the ability of clinical reasoning and critical thinking; (iv) to cultivate nursing students’ professional ethics. Twelve teachers teach Medical Nursing. All of them underwent the same training regarding the specific processes of blended learning and offline case-centered learning. In addition, collective lesson preparation (involving all the teachers) was conducted before teaching each chapter in order to guarantee high-quality teaching.
The same teachers, textbook, and references were provided to both groups. The experimental group underwent blended case-centered learning including online and offline learning, whereas the control group totally underwent offline case-centered learning (Table 1). Notably, whether in lectures, flipped classrooms, or seminars, the teaching method involved case-based learning. Although blinding of the students and teachers was not possible, the data analyst was blinded.
Experimental group
Apart from traditional face-to-face lectures in class, there were three stages in the implementation of the blended case-centered learning, comprising before, in, and after each flipped classroom (Figure 1).
Before the flipped classroom
All students were required to log in the Chaoxing platform (http://i.mooc.chaoxing.com/space/index.shtml), which allowed them to watch the pre-recorded lecture videos and access the online forums, and study materials. Before the flipped classroom, group cases study was also required and necessary. Students subsequently divided into subgroups (approximately five students per subgroup) to discuss the cases and the questions that the teacher provided prior to the class. In addition, they recorded the whole process of their discussion, produced a report, and handed in the recording and the report after the discussion. Questions could be asked online anytime.
In the flipped classroom
Each flipped classroom involved one group, with approximately 20 students, and they were divided into four subgroups (with approximately five students per subgroup) based on the pre-class group discussions. To assess the students’ mastery of the lesson prior to class, online quizzes, which lasted approximately 10 min, were performed at the beginning of the flipped classroom. Subsequently, the teacher provided detailed explanations of the quiz questions according to the students’ results, then the students reported what they had discussed prior to class. After each subgroup completed the reporting, other subgroups asked questions or provided supplementary answers. The teacher commented on each report and summarized the results of the group discussions. Additionally, the teacher pointed out the problems that the students needed to pay attention to in their study, and guided the students to think and discuss according to the discussions and feedback. Towards the end of the class, the teacher guided the students to review and summarize the important knowledge points of the lesson.
After the flipped classroom
After the flipped classroom, the students were requested to submit homework to the platform, raise questions in the online forums or review teaching videos. All study data were recorded via the platform and could be accessed by the teachers.
Control group
The control group underwent offline case-centered learning via traditional face-to-face lectures and seminars throughout the two semesters (Figure 2). Before the seminar, the students were required to preview the textbook. Each seminar involved one group, with approximately 20 students. During each seminar, students formed subgroups to discuss the cases under the guidance of the teacher. Subsequently, the teacher randomly selected subgroups to answer questions. Comments and explanations were provided by the teacher according to the answers. Additionally, the teacher guided the students to think, discuss, and summarize the knowledge points of the class. When class was almost over, a quiz was conducted to monitor the students’ mastery of the lesson. After the seminar, the students were required to finish the homework and summarize the key knowledge points and then submit the learning notes.
Measurements
Academic performance
The Medical Nursing assessment contains two parts, the final exam and the process assessment. The maximum total score for the course was 100. The total score was determined using the weights (Table 1).
Both the experimental and control groups underwent exactly the same final exam, quizzes, and homework. All the questions in the exam and quizzes were carefully developed by the teacher team. The content validity of the examination questions was 0.9. The test-retest reliability method was impossible to be calculated, we could only improve the reliability by keeping the examination questions confidential, ensuring strict examination discipline, and conducting unified examinations.
Assessment of the critical thinking ability of students
The California Critical Thinking Disposition Inventory (CTDI) has been specifically developed and used for nursing students [37]. It has been shown to be a valid instrument for assessing critical thinking ability among nursing students in different cultural contexts [38]. The population included in the present study consisted of Chinese students. Hence, the CTDI-Chinese Version (CTDI-CV), which was translated, modified, and validated by Chinese researchers, was more suitable than the original [39]. The CTDI-CV exhibits a good overall content validity index (0.89) and Cronbach’s alpha (0.90), indicating satisfactory content validity and internal consistency, respectively [39].
The CCTDI measures overall critical thinking disposition. It consists of seven subscales that measure the following dispositions: truth-seeking, open-mindedness, analyticity, systematicity, critical thinking self-confidence, inquisitiveness, and cognitive maturity. Potential scores range from 5 to 60 for each subscale, with a maximum total score of 420. The students in the two classes completed the questionnaire prior to and following the teaching experiment. The internal reliability coefficients (Cronbach’s alpha) in our study were 0.86 (pretest) and 0.87 (posttest), and the values for the subscales ranged from 0.73 to 0.82.
Ethical considerations
Approval was obtained from the Research Ethics Committee of Fujian Medical University. The participants were informed that they had the right not to participate and could withdraw from the study at any time. Written informed consent was obtained from all students who agreed to participate in the study. We informed the participants of the purpose, content, and extent of the study, and guaranteed that their responses were confidential.
Data collection procedure
The data collection procedure was explained to all participants, and information regarding the estimated time and number of contacts with participants was provided. Students who agreed to participate in the study were asked to provide demographic data and outcome data (critical thinking assessment) in a pretest assessment conducted during the meeting in which they were enrolled in the study. Outcome variables were measured again 1 school year after the intervention, as a posttest assessment. Additionally, we collected the final course grades of the participants. The participants were not subject to any physical, psychological, social, or economic harm or risk, as the data collection procedure primarily relied on a descriptive, noninvasive questionnaire on each student’s demographic characteristics and critical thinking ability.
Data analysis
All statistical analyses were conducted using Statistical Package for the Social Sciences (SPSS), version 22.0 (IBM Corp., Armonk, NY, USA). Mean and standard deviation were used to represent the normally distributed continuous data, while median (M) and quartiles (P25-P75) were used to represent the non-normally distributed continuous data. If the continuous variables were normally distributed and exhibited homogeneity of variance, the t-test was used to assess the difference in learning outcomes between the two groups. Otherwise, the nonparametric rank-sum test was used. A Shapiro-Wilk test was first performed to verify the normal distribution of the academic performance data, and the Mann-Whitney U test was subsequently used. We used the two-tailed approach for the unpaired t test. In addition, ANCOVA analyses were performed to examine the two teaching methods’ effect on critical thinking. The significance level was set at 0.05.