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    Application of online pre-class questions and double feedback improves student performance in the teaching of medical histology*

    2021-03-02 01:41:08LiYanZhengHuaZengYongZhouGuominMaShulan0003
    解剖學(xué)雜志 2021年1期

    Li Yan,Zheng Hua,Zeng Yong,Zhou Guomin,Ma Shulan(,,,,3,,0003,)

    The trend in histology teaching is gradually reducing face-to-face time and switching from teacher-oriented learning approaches to student-centered ones[1-4].In order to engage students in the learning process,many novel technologies and electronic resources have been used by researchers,including virtual microscopy,lecture videos,and interactive response systems[5-7].Participants in these studies have expressed positive attitudes toward these novel methods,regardless of whether they experienced performance improvement after using them[5,7].

    Although electronic resources have been developed and assessed during histology education in some institutes,these resources may poorly align with the Chinese histology curriculum[5-9].Yet,a recent study showed that medical students in the University of Sydney prefer online question banks,including Passmedicine,PasTest,and OnExamination for supplementary learning,while traditional resources such as lectures and textbooks remain the most popular for learning new materials[10].Based on our initial survey,Chinese undergraduate medical students use questions banks in the same way.Therefore,to develop online questions uniquely suited to Chinese medical students is imperative for their learning success.In addition,higher-level Bloom's taxonomy questions were proven to help educators diあerentiate between higher- and lower-performing students[11],and to help them obtain accurate information on student understanding.Imagebased questions were assigned a higher cognitive order than the simple text questions which comprised the main assessment style of Chinese histology courses[11].Moreover,this imagebased question style has been shown to significantly enhance medical students' academic performance[6].These findings suggest that in addition to the content of questions,the format of questions is important.Questions,therefore,should be designed in such a way that they incorporate these features.

    Feedback is defined as information provided by an agent(e.g.,teacher,peer,book,experience)regarding aspects of one's performance or understanding[12].Studies have reported that millennial students have a desire for feedback,especially from instructors[13].As such,educators should design their courses with ample opportunities to provide students with feedback.Moreover,a meta-analysis of published articles showed that feedback was one of the strongest factors determining success in any educational activity and had a long-term impact on learner academic success[14-15].More recently,a cloud-based assessment system was adopted in a laboratory course of histology at Cornell University for providing immediate formative feedback to students about their progress[7].Similarly,in an earlier study,researchers at the Mayo Medical School in the United States tested automated response software technology and found it a reliable assessment method that enhanced student performance[5].In view of the fact that feedback is an interactive process and interactivity is a key function of online systems,an online technology was introduced in this study to assist educators in providing prompt feedback.In addition,delaying feedback is also necessary,especially for difficult topics and for developing the ability of transferring knowledge to new problems[14,16].So,both preliminary feedback from an online system and delaying targeted one from teachers should also be performed and examined in this study.

    Computer-aided instruction provided before traditional lectures has been shown to be more eあective than computeraided instruction provided after lectures[17].Similarly,the flipped classroom,where students are required to study electronic materials before a lecture begins,has been considered an eあective approach[18].Ultimately,these studies showed that previewing materials was helpful for learning.However,our preliminary survey demonstrated that a percentage of Chinese undergraduate medical students seldom previewed textbooks.Therefore,the authors of the present study determined that it would be valuable to design a step where students completed online questions before class.To complete this step and answer the questions,students would need to preview the textbook.

    With those considerations in mind,the authors designed high-level questions.A cloud-based technology was used to disseminate questions and collect responses before classes began.Finally,during laboratory sessions,one teacher provided specific,elaborative,and illustrative feedback to students based on their answers to pre-class questions.Our hypothesis was that via this strategy for an enhanced studentcentered learning experience,student performance would be improved.

    1 METHODS

    1.1 Student participants

    The sample consisted of 224 sophomores(classes of 2016 and 2017)from the Clinical Medical Program who were enrolled in the “Medical Histology” course at Fudan University.Of these,216 students provided the data necessary for completion of the statistical analyses.The male/female ratio was 102/114(47.2%vs52.8%).Their ages ranged from 19 to 21.Participants' average GPA was 3.26.At the beginning,a teaching director divided students randomly into the user group and non-user group.Students in the user group were exposed to the course change while students with no exposure were treated as the non-user group(control).The present study was approved by the Ethics Committee of Fudan University and conducted in accordance with the Declaration of Helsinki.

    1.2 Course context

    The course was designed for undergraduate students at the School of Basic Medical Sciences,F(xiàn)udan University.During the second year,the histology curriculum covering fundamental tissues and all organ systems was taught over a 15-week semester.The weekly class consisted of one 90-minute,traditional style lecture and one subsequent 135-minute faculty-guided laboratory session.In total,contact hours include 22.5 hours of lectures and 33.75 hours of laboratory sessions.Lecture sessions were delivered to groups containing an average of 100 students each.Five academic doctoral faculties participated in the lecture portion of the study,and were in charge of 2 or 3 subjects each.The 15 laboratory sessions were delivered to smaller groups with a maximum of 32 students each.Each such group was facilitated at all times by one faculty instructor.In order to ensure homogeneous knowledge of the topics,all faculty members had bi-weekly meetings.

    The first 30 minutes of a typical laboratory session included a PowerPoint presentation administered by one teacher,and the remaining time was apportioned for viewing glass slides with students' own light microscopes which were set up in the laboratory rooms.During the viewing process,each student followed the in-house paper laboratory manual including detailed description of suggested slides and color images.Students produced actual drawing of the typical structures they viewed under the microscope and were asked to generate laboratory reports six times per semester.After course hours,the glass histological slides were no longer available,increasing students' difficulty in studying and learning histology.

    1.3 Description of user group instructional materials

    To more deeply involve user group students in the learning process,this study was performed during both the pre-laboratory and main laboratory sessions.Prelaboratory questions focused on the following specific problems:student misconceptions and the shortage of connecting present knowledge with previous knowledge.These targeted questions more easily stimulated students'interest and guided them to deeper learning than untargeted questions did.Image-based multiple-choice questions and multiple-response items were introduced instead of traditional simple-text questions.For example,cells of the alveolar wall needed to be identified in caution.A multiplechoice question was with reference to this micrograph showing the alveolar wall(a HE image with two arrows pointed to two cells),which one of the following statements is true?Choices were ① The cells indicated with an arrow are capillary endothelial cells;② The cells indicated are alveolar macrophages;③ The cells indicated are type I pneumocytes;④ The cells indicated are smooth muscle cells;⑤ The cells indicated are type II pneumocytes.Correct answer was choice⑤.Fifteen modules containing four to five questions each were designed around all histological topics,such as four basic tissues and all organ systems.The modules were delivered as ten to thirty-minute preview portions.The modules were opened one week prior to the laboratory class and closed when the class began.

    The study used Zuvio,a cloud-based real-time interactive teaching software,to disseminate the questions and collect students' replies.As of early 2019,Zuvio had been used by 7,025 teachers and 220,083 students.This tool had the following advantages:① Students could utilize it on any web-enabled device(such as smart-phone,iPad or computer).Login and verification were required so as to protect confidentiality,and then students accessed the online questions;②Students' replies could be recorded,analyzed statistically,and viewed on instructors' devices.This allowed instructors to not only know the real state of students'knowledge on every question,but also to effectively grasp individual details regarding learning outcomes.Importantly,the latter was beneficial for identifying lower-performing students and immediately providing them with direction;and③The software was available,free of charge,for all students and teachers at Fudan University and was serviced in real time by special technicians.

    Before the laboratory classes began,instructors analyzed students' responses in Zuvio to decide which parts should be emphasized during the subsequent laboratory session.If most students answered a question incorrectly,then a teacher explained the answer in depth and pointed out the subtle difference between confusing choices.Similarly,if most students answered it correctly,that question would be left out of the class.If an individual's answers were perfect,they were shown to all studentsviaa projector in the classroom.On the other hand,if an individual's answers were mostly incorrect,an instructor inquired into the reasons.

    In the laboratory class,an instructor provided specific and illustrative feedback,based on student data from Zuvio,through appropriate approaches such as several minutes of lecture,demonstration of perfect peer work,and guiding the direction of the observation of glass slides.This was diあerent from the experience-oriented oral feedback provided by instructors in the non-user group.

    1.4 Assessments

    Formal histology assessments included quizzes(4%),written laboratory and topic reports(11%),two practical activities(25%),and one summative final examination(60%).The low-risk written assignments and quizzes were designed to prepare students for the examination.The final examination covered materials from the entire semester and was used as a means to objectively assess academic performance of students.

    The final examination consisted of multiple-choice questions,fill-in-the-blank items,short-answer questions,and essay questions.On the day of the examination,identical examination papers were delivered to all students involved in this study.The same teachers graded all papers,with each one in charge of particular parts,thus allowing for direct comparison of learning outcomes.The test scores on the final examination from both groups of students were collected by two teaching staff members who were not involved in the study.

    1.5 Surveys

    Following the final module,the two questionnaires were distributed to students.Completed questionnaires were analyzed to obtain information.The first questionnaire was used to obtain information about students' histology learning behaviors.The second questionnaire was designed to evaluate how students experienced the online questions delivered via Zuvio.The survey items were initially drafted by the authors to promote content validity.Then they were tested by a medical student(T.S.Y.)to assess clarity.Further,two faculty members with expertise and significant experience in survey research methodology(F.Y.and Z.Y.)also reviewed and edited the items.Each close-ended question had two to five possible answers.Answers from paper-based questionnaires were typed verbatim into a Microsoft Excel spreadsheet for analysis.KMO and Bartlett's test of sphericity and Cronbach alpha statistical tests were performed to assess the validity and reliability of the close-ended items using SPSS 22 software(IBM Corp.,Armonk,NY).

    1.6 Data analysis

    IBM SPSS Statistics,version 22(IBM Corp.,Armonk,NY)was used to perform statistical analysis.Descriptive statistics including percentages,means,and standard deviations(SD)were calculated for each question.Students'responses and the final cumulative histology scores between the two groups were compared with T-test or Pearson's chisquared test.Results of the statistical analyses were presented as the mean ± SD,or percentages.AP<0.05 was considered statistically significant.

    2 RESULTS

    2.1 Summative assessment results

    In order to investigate the effect of this strategy on exam performance,the authors compared the mean scores on the final summative examination between non-user and user groups.The results were shown in Tab1.Considering two different test papers in the class of 2016 and 2017,the authors separately calculated the difference between the two groups.For the class of 2016(n=109),students in the user group scored better than those in the non-user group,which was statistically significant.The same result was seen in the class of 2017(n=115).This suggested that this new strategy improved students' learning performance.

    Tab1 Comparison of final summative examination scores between students in user and non-user groups(±s,%)

    Tab1 Comparison of final summative examination scores between students in user and non-user groups(±s,%)

    n:Number of respondents

    Group Non-user(n)User(n)P Class 2016 50.6±22.2(54)61.4±16.6(55)<0.01 Class 2017 59.1±20.2(57)66.6±18.4(58)<0.05

    2.2 Students' learning behaviors

    To determine whether there were differences in learning behaviors between user and non-user groups,the first questionnaire was distributed to the class of 2017(n=115).The response rate was 96.5%(111/115).Qualitative results for these items were displayed in Tab2.It is noted that paper textbooks were the designated materials to study,which is routine in China.The frequency of previewing paper textbooks was answered on a five-point Likert scale.Mean Likert scores were 2.96±1.05(non-user)and 3.61±1.07(user),respectively(Tab2).A statistical analysis indicated that the diあerence was significant.Further,Spearman's rank correlation test proved that the use frequency of online questions was positively correlated with the frequency of previewing paper textbooks(Spearman's rho=0.412).In addition,a higher percentage of the usergroup made use of non-assigned histology resources(Tab2).This data suggested that this new strategy improved students'learning behaviors.

    2.3 Describing students'usage

    The second questionnaire was presented to the classes of 2016 and 2017.Only students who used online questions were asked to provide their perceptions(n=113).The response rate was 94.7%(107/113).The student responses regarding utility and usability were shown in Tab3.Among the students,86.7%(n=105)reported that this online system was convenient.In addition,90.5%(n=105)of the students were satisfied with this strategy,including the 15 modules of pre-class online questions and double feedback.Moreover,students found this strategy helpful for learning(91.4%,n=105)and increasing the frequency of previewing the assigned paper textbooks(77.6%,n=107).

    Tab2 Comparison of student responses on learning behaviors between user and non-user groups (the class of 2017)

    Tab3 Average responses of students in user groups on this strategy(classes of 2016 and 2017)

    To further observe the effect of this new strategy,students in the user group(classes of 2016 and 2017,n=107)were further divided into high-frequency of use group and lowfrequency of use group depending on their frequency of use of the online questions.The average final cumulative histology score was calculated and tested for statistical significance.For the class of 2016,students with high-frequency of use had a higher mean score(64.7%±16.3%)than those with low-frequency of use(53.9%±19.4%)(P<0.05).AlthoughP-value was 0.172 for the class of 2017,there was an increase(69.3%±18.4%vs62.4%±18.1%)in the high-frequency of use group.Moreover,students with high frequency of use more strongly affirmed that this strategy was helpful for learning(Tab4),especially with respect to increasing the frequency of previewing paper textbooks(89.8%,n=58),which are the objectives of this study.

    Tab4 Comparison of student responses on this strategy between groups of low-and high-frequency of use (classes of 2016 and 2017)

    3 DISCUSSION

    This study shows the impact of pre-class online questions and double feedback on student performance.

    Pre-class questions are key factors in gauging students'understanding of materials[11].The quality of these questions directly influences identification of students' ability.For example,teacher-generated questions were shown to better differentiate between low-and high-performing students than questions students wrote[7,11].This suggests that questions from instructors are more helpful.Specifically speaking,the content of the authors' questions in the present study was based on observed problems in student practice.Because this approach is targeted and therefore different from general questions,we hypothesized a strong effect.In addition,the challenging image-based style selected for the questions,was considered on a higher level than simple text questions and had been proven to be beneficial for knowledge construction[11,19].In this study,students with high-frequency of use had a significant increase in final examination scores over students with low-frequency of use.This is consistent with the results presented by another study with the same question style[6].

    To preview materials is a learning strategy which encourages students to prepare for the following session and pay additional attention to trouble points.This is a good learning behavior,but some Chinese undergraduates only minimally preview the assigned content.In order to involve them in previewing the designated paper textbooks,the online questions were released only 1 week in advance of when class began.The results showed higher frequency of previewing the textbooks after this strategy(Tab2).Moreover,in the group of highfrequency users,there was a higher percentage of persons rating the helpfulness for previewing paper textbooks(Tab4).In addition,to actively choose non-assigned materials was considered a sign of active learning.The results in Tab2 indicated this behavioral shift.The significant results indicated that this strategy could improve students' learning behaviors,which in turn would increase students' academic success.

    It has been reported by an overwhelming number of studies that the most eあective feedback should be corrective and specific[12,14,20].Students in the present study first responded to online guiding questions which were designed purposefully by teachers and then obtained preliminary feedback via the online system in the form of the answer key.Then they received specific,explanatory,and elaborative feedback provided by the teachers.With this format of test and feedback,students on average received double confirmation of correct answers and other reinforcement,which is diあerent from experience-oriented general feedback provided by instructors in non-user group.This may have resulted in the improvement of students' outcomes.It is also important to note that the timing of feedback can be immediate or delayed.Generally,immediate feedback has been received more easily by students than delayed feedback[16,20].However,sometimes delaying feedback is necessary,especially for difficult topics[14].This may be due to learners' needing extra time to process the information.Delayed feedback has been proven to enhance long-term retention and transfer of existing knowledge and known concepts to new problems[16].In this study,after giving the first feedbackviathe online system,teachers provided second delayed feedback according to students' replies to online pre-class questions.The combination of immediate and delayed feedback in the course promoted students' knowledge construction and self-learning.

    Interactive systems are becoming popular tools in medical histology courses[5,7-9].Students were able to use the system to continuously monitor their progress and get clear feedback during the curriculum,which was helpful for the learning process.Information processing is a strategic learning skill,which has proved to be significantly correlated with students'learning outcomes in histology[21].Studies reported that students valued the system and obtained good performance during histology education[5-7].This was also supported by the results of the present study.In addition,this system allowed for individualized feedback,which teachers use to clearly identify histology learners in academic trouble[5,7].The present study's system also played this role.

    Application of pre-class online questions and specific feedback improves student-centered learning and student performance in medical histology.This study provides guidance for optimization of student-centered learning in other medical courses.

    ACKNOWLEDGEMENTS

    The authors acknowledge the Zuvio team for allowing the use of their interactive software free of cost during this research.We would also like to thank Taylor & Francis Editing Services for English language editing.

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