The effects of an active learning mechanism on cognitive load and learning achievement: A new approach for pharmacology teaching to Taiwanese nursing students
Introduction Pharmacology is included in Taiwan's Registered Nurse Examination and is a part of the professional knowledge required by nurses in their daily work. To work in the complex healthcare system, pharmacology has been a required course in nursing education . Studies have noted that the major cause of medication-related errors is insufficient pharmacological knowledge . revealed that improvements in pharmacological knowledge and the quality of clinical practice among nursing students were crucial to avoid medication-related errors. According to , nurses believes that nursing education should be strengthened in this field, including areas such as “disease and drug treatment”, “the latest pharmacological knowledge”, and “adverse drug reactions” to reduce medication–related errors. Pharmacology is a difficult subject for nursing students in Taiwan. The traditional teaching relied on memorization and lacked of understanding. Therefore, educators should design appropriate and effective pharmacology-related learning strategies for nursing education. In this study, we applied active learning mechanism in a pharmacology course. As stated by , active learning requires the student to actively develop knowledge instead of passively receiving it from the teacher. also demonstrated that active learning yields better learning outcomes relative to passive learning. Research has also indicated that encouragement boosts student's learning motivation, and self-efficacy . In the active learning process, feedback helps students gain self-confidence and understand where gaps in their knowledge lie . The aim of this study is to design interactive digital learning materials integrated with active learning mechanism, composed of “explanations”, “quiz and feedback”, and “encouragement” to improve nursing student's achievement in studying pharmacology. In this course, students participated in an active learning manner at a time, place, and pace of their choosing.   Background Numerous studies have introduced teaching strategies to help nursing students learn pharmacology, including facilitating memorization of pharmacological knowledge, application of pharmacological theory and increasing learning satisfaction. noted that learning pharmacology from a textbook is tedious because of the lack of interaction. Alternately used a complexity-based computer model to assist nursing students studying pharmacology. The aforementioned model helped students understand pharmaceutical biochemical phenomena, enhanced their learning efficiency, supported their clinical decision-making and improved their clinical treatment experience. Another approach by introduced an effective synchronous teaching method for nursing students to learn pharmacology. To compare the learning outcomes of postbaccalaureate nursing students studying pharmacology in flipped and traditional classrooms, the results from revealed no significant difference in test scores between the two teaching methods. However, the traditional classroom method received higher satisfaction scores than the flipped classroom, which was attributed to the heavy burden on students from pre-class learning required in the flipped classroom. redesigned the course contents for a flipped classroom to reduce the time that students spent studying before class, emphasizing the key concepts related to 25 topics totaling 14.4 studying hours equivalent to an average unit length of approximately 35 min before students entering the classroom. All lectures were uploaded in the form of self-paced online videos and class time was used to engage students in active learning exercises. Some researchers believe that this method is beneficial for learning in anatomy  and environmental soil science . In addition, the flipped classroom has been demonstrated to be helpful for nursing students studying advanced pathology and pharmacology as part of the midwifery course . Incorporating an active learning strategy has been shown to predict better student performance . As defined by , active learning is student centered and participatory. It is often associated with constructivist theories of learning, whereas students learn by actively challenging and critiquing concepts that they have developed through their experiences  possibly under the guidance of a teacher who encourages the necessary cognitive challenges . Active learners generally show more effective achievement . In recent years, the “student-centered” teaching model has allowed students to preview digital learning materials before in-class discussion . With the growth of multimedia, learning materials have become more diverse. Interactive learning materials that support teaching are more popular, but their design is the key. demonstrated that appropriate learning materials, such as integrated multimedia teaching resources that present key information, may increase the efficiency of the self-learning process. Research on the effectiveness of digital learning materials in physiology and anatomy courses revealed that the use of such materials could enhance students' performance and satisfaction in these courses . When students learn through active participation, their learning effectiveness improves. In this study, we adopted interactive learning materials with an active learning mechanism to help nursing students' pharmacology learning. As mentioned, active learning involves students' efforts to actively construct their own knowledge. In this course, students are free from the constraints of the time, pace and place for study with the same learning outcome expectations. We hypothesized that when students make efforts, through instructor's feedback and encouragement, their desire to learn would increase. With the development of multimedia learning materials, cognitive load has become an issue. Cognitive Load Theory (CLT) can serve as a reference when teachers develop innovative teaching materials in consideration of the limitations of human cognitive architecture . CLT can be divided into intrinsic, extrinsic, and germane cognitive load . Intrinsic cognitive load refers to the inherent difficulty of the learning material itself and the learners' experience or knowledge . Extrinsic cognitive load relates to poor learning material design or poor-quality interfaces, requiring extra cognitive resources for processing irrelevant information during the learning activity . Germane cognitive load refers to material design that helps students establish a knowledge base, using repetition, organization, comparison, and deduction to aid memorization. Intrinsic cognitive load cannot be modified by teaching interventions because it is an internal factor of the material being processed; extrinsic cognitive load is an unnecessary cognitive load, which can be altered through teaching interventions; and germane cognitive load is an effective cognitive load, resulting from beneficial cognitive processes . Multimedia learning is defined as a learning process using pictures and words to construct mental representations . CLT addresses how individuals process information, how they learn through multimedia, and how interactive learning materials play a key role in the digital learning process. The present study developed an active learning mechanism consist of three phases of “explanation”, “quiz and feedback” and “encouragement” to support the presentation and use of interactive learning materials in pharmacology learning for nursing students. To evaluate the learning effectiveness of the proposed approach, an assessment of the cognitive load resulting from use of the digital learning material was conducted among junior college nursing students. With the use of properly designed learning materials, we expected our active learning mechanism could effectively reduce the cognitive load of learners. The objectives of the study included: 1. To examine if an active learning mechanism helps nursing students learn pharmacology more efficiently through interactive learning materials. 2. To demonstrate that cognitive load is not increased in nursing students studying pharmacology using interactive learning materials. 3. To demonstrate that learning achievements are elevated in nursing students studying pharmacology using interactive learning materials.   Methods In junior nursing colleges in Taiwan, introductory pharmacology is a foundation course designed for second-year nursing students before commencing the integrated medical–surgical nursing course and basic nursing clinical practice. Approximately 250 students each semester take this two-credit course that consists of one 100-min class per week. 3.1 Design and participants An experiment was designed to evaluate the benefits of the redesigned digital learning material on nursing students studying pharmacology based on students' learning achievements and cognitive load. The redesigned digital learning material was linked to each unit of the introductory pharmacology course. The purpose of this course is to describe the mechanisms underlying normal function and abnormal physical conditions. In addition, students learn about the types of drugs used to treat diseases, how they affect body systems, and the precautions required when managing drugs. Students used the “Explanation”, “Quiz and feedback” and “Encouragement” active learning mechanism, which is followed by exercises that involve interactions with the digital learning material, a quiz, and feedback, to acquire the basic knowledge required for this course. The participants came from four classes of second-year nursing students in National Tainan Junior College of Nursing in Tainan City, Taiwan. As calculated using GPower 3.1.9.4, a sample size of at least 171 was required to achieve a statistical power of 0.9 for an anticipated effect size of 0.25. Thus, we recruited 188 participants, whose data were analyzed using analysis of covariance (ANCOVA); 98 and 90 students were assigned to the experimental and control groups, respectively, through cluster sampling . The experimental group used redesigned multi-media interactive learning materials, and the control group used traditional textbooks to study the same topics. In this course, a teacher designed the digital learning materials based on the active learning approach, planned the course schedule, and prepared the test items. The teacher also provided technical assistance for the digital learning materials to students in the experimental group. Researchers observed on whether students diligently read the material and took quizzes as part of the learning. Students were asked to give feedback on their learning experiences to the teacher after the course. 3.2 Instrument 3.2.1 Design of the interactive pharmacology learning materials using the active learning mechanism Learning materials play a key role in learning. The use of learning materials makes teaching easier and facilitates the learning process for students. noted that developing learning materials suited to the learning goals and that engage learners is challenging. Learning pharmacology is difficult for nursing students because of the complexity of the subject. Students must learn the mechanisms, classifications, side effects, pronunciation of each drug, and much more. Therefore, when learning materials can guide students effectively in their study, they become more engaged. In this study, we developed interactive learning materials that integrated digital technology and the active learning mechanism using interactive teaching material production software. The critical elements of the drug mechanism of action were presented step-by-step in the learning material. In this study, we presented interactive teaching materials on asthma treatment drugs as an example to demonstrate the applicability of our active learning approach while all other topics were designed on the basis of the same conception of active learning. The learning material consists of two parts: instruction and interactive quizzes. 3.2.1.1 Part 1: instruction This part starts with a sthma pathophysiology . The critical factors related to asthma were described, followed by the drug mechanisms of action. Lastly, based on the drug classification, the side effects and precautions of common clinical drugs were introduced. 3.2.1.2 Part 2: interactive quizzes After Part 1, students appraised their learning outcomes through interactive quizzes. A question bank contains all the questions organized for the following three functions: the first guides the nursing students to review the asthma pathophysiology, the second strengthens the concept of pharmacological mechanisms, and the third reviews the side effects and precautions after integrating the pathophysiological and pharmacological concepts. The active learning mechanism consists of three parts, namely “explanations”, “quiz and feedback”, and “encouragement”, which is a part of the active learning cycle, as illustrated in . 1. Explanations: This is a step-by-step process covering the key concepts from the physiological mechanism to drug side effects. Pathophysiology is a chain reaction; however, drugs mainly improve pathophysiological responses through the antagonism of receptors and others. The step-by-step learning material and teacher's narration assisted nursing students to understand the mechanism of drugs. The learning material helped nursing students integrate their physiological, pathological and pharmacological knowledge. In this learning process, students were able to control the play mode (slow, quick, replay, or skip) based on their familiarity with the content. 2. Quiz and feedback: Students verified their learning achievement through narrative quizzes. For example, “how do the allergens destroy physiological mechanisms and cause abnormal states?” If the answer is correct, the active learning mechanism congratulates the student and provides feedback. However, if the answer is wrong, it provides hints and encouragement. 3. Encouragement: An exhausted question bank indicates that a student had correctly answered all the questions. This means that a student accomplished the learning task related to a particular learning goal. Students can then choose the next learning objective. During the quizzes, feedback is provided after answering each question. Students are congratulated when the answer is correct, and encouragement is provided when the answer is wrong. Timely encouragement could make students feel self-confidence and self-efficacy . This learning mechanism raised student's motivation. A part of the interactive learning materials related to drug treatment of asthma are shown in . In the design process, the interactive learning materials are integrated into the active learning mechanism. They were interactive and featured, spoken and visual and game-based learning aids (such as when a student is prompted to match a side effect with a drug when playing a game. Please see ). The interactive learning materials with the active learning mechanism were uploaded to the college's digital platform. Students could access the platform in their own time within the time limit specified by the teacher. The learning materials and interactive quizzes have no time limits. Students can increase their understanding and memorize more information through multiple viewings of the contents and unlimited number of attempts to the quizzes. 3.2.2 Cognitive load scale for digital reading of pharmacology Studying introductory pharmacology using the interactive learning materials was a new experience for the nursing students. Our goal was to understand the intrinsic and extrinsic cognitive load of the nursing students during the learning process and their learning achievement. This study developed a cognitive load scale for digital reading of pharmacology (CLSDR_P) based on the literature . According to , prequiz and postquiz results can indicate the germane cognitive load in the two groups. Therefore, we used prequiz and postquiz as the assessment of learning achievement, as well as the evaluation of germane cognitive load. 3.2.2.1 Factor analysis The items of the CLSDR_P were developed and modified based on the literature  and validated through focused discussion by the expert panel consisting of five experts. Based on the recommendations of the expert panel, the CLSDR_P was consisted of 14 items. The response options are a seven-point Likert scale (ranging from 1, “strongly agree” to 7, “strongly disagree”). We invited 200 nursing students who were taking pharmacology courses to complete the survey and conducted exploratory factor analysis to validate the factors in the cognitive load scale. To ensure the validity of the items, the items with factor loading less than 0.5 were removed from the survey. displayed the factor analysis results and revealed two factors, namely “intrinsic cognitive load” (six items) and “extrinsic cognitive load” (eight items). These factors accounted for 73.2 % of the variance. The eigenvalues of the two factors from the principal component analysis were both larger than 1, and the reliability (Cronbach's alpha) coefficients for these scales were 0.916 and 0.956, respectively, with an overall alpha of 0.947. The CLSDR_P was considered to be adequately reliable for assessing nursing student's intrinsic and extrinsic cognitive load in relation to the pharmacology interactive learning materials. 3.2.2.2 Reliability and validity In addition, we invited 50 nursing students who were taking pharmacology courses to determine reliability. Reliability was tested by internal consistency analysis. Cronbach's alpha was calculated whereby a Cronbach's alpha higher than 0.8 was considered satisfactory . The CLSDR_P had a Cronbach's alpha value of 0.922 and 0.934 for items on intrinsic and extrinsic cognitive load, respectively. The CLSER_P was also determined to be valid by a panel of five experts, including one senior pharmacist, one senior pharmacology instructor, two senior nursing instructor, and one professor of science education. It had acceptable content validity , with content validity indices (CVI) of 80.5 %. 3.2.3 Online quiz Learning achievement was evaluated through their online prequiz and online postquiz scores. The prequiz aimed to assess the students' prior knowledge of basic physiology and pathology include consisted of 50 multiple choice questions with a maximum score of 100. The postquiz was used to evaluate the nursing students' learning achievements after using the interactive learning materials. It was composed by 50 multiple choice questions with a maximum score of 100. The prequiz and postquiz were designed by the teachers who taught the introductory physiology and pharmacology course and were evaluated by three educators from related fields for expert validity. 3.3 Experimental procedure showed the experimental design. The experiment lasted for 6 weeks. Before the study, all nursing students had received instruction on physiology and pathology. They then completed a questionnaire to measure their cognitive load and took a prequiz. In the first week, an orientation was given to help students of the experimental group learn to use the interactive learning materials. In the second week to fifth week, students of the experimental group learned the topics including the anti-hypertensive drugs, asthma treatment drugs, peptic ulcer treatment drugs and nonnarcotic drugs using the interactive learning materials. The students of the control group studied using a traditional pharmacology textbook to learn the same topics. After the experiment, the two groups completed a questionnaire to measure their cognitive load and took a postquiz. 3.4 Ethical considerations Permission to undertake the research was obtained from National Cheng Kung University Human Research Ethics Committee, Taiwan (approval no. NCKU HREC-E-109-342-2). Prior to the research, all students were informed of the purpose of the study and the written informed consent was obtained from the students and their parents/guardians. 3.5 Data analysis SPSS 26.0 software was used to perform the statistical analysis, with an analysis of covariance (ANCOVA) used to analyze learning achievement. A factor analysis was performed to analyze the reliability of cognitive load scales. Finally, ANCOVA was used to examine the differences in intrinsic and extrinsic cognitive loads between the experimental and control groups.   Design and participants An experiment was designed to evaluate the benefits of the redesigned digital learning material on nursing students studying pharmacology based on students' learning achievements and cognitive load. The redesigned digital learning material was linked to each unit of the introductory pharmacology course. The purpose of this course is to describe the mechanisms underlying normal function and abnormal physical conditions. In addition, students learn about the types of drugs used to treat diseases, how they affect body systems, and the precautions required when managing drugs. Students used the “Explanation”, “Quiz and feedback” and “Encouragement” active learning mechanism, which is followed by exercises that involve interactions with the digital learning material, a quiz, and feedback, to acquire the basic knowledge required for this course. The participants came from four classes of second-year nursing students in National Tainan Junior College of Nursing in Tainan City, Taiwan. As calculated using GPower 3.1.9.4, a sample size of at least 171 was required to achieve a statistical power of 0.9 for an anticipated effect size of 0.25. Thus, we recruited 188 participants, whose data were analyzed using analysis of covariance (ANCOVA); 98 and 90 students were assigned to the experimental and control groups, respectively, through cluster sampling . The experimental group used redesigned multi-media interactive learning materials, and the control group used traditional textbooks to study the same topics. In this course, a teacher designed the digital learning materials based on the active learning approach, planned the course schedule, and prepared the test items. The teacher also provided technical assistance for the digital learning materials to students in the experimental group. Researchers observed on whether students diligently read the material and took quizzes as part of the learning. Students were asked to give feedback on their learning experiences to the teacher after the course.   Instrument 3.2.1 Design of the interactive pharmacology learning materials using the active learning mechanism Learning materials play a key role in learning. The use of learning materials makes teaching easier and facilitates the learning process for students. noted that developing learning materials suited to the learning goals and that engage learners is challenging. Learning pharmacology is difficult for nursing students because of the complexity of the subject. Students must learn the mechanisms, classifications, side effects, pronunciation of each drug, and much more. Therefore, when learning materials can guide students effectively in their study, they become more engaged. In this study, we developed interactive learning materials that integrated digital technology and the active learning mechanism using interactive teaching material production software. The critical elements of the drug mechanism of action were presented step-by-step in the learning material. In this study, we presented interactive teaching materials on asthma treatment drugs as an example to demonstrate the applicability of our active learning approach while all other topics were designed on the basis of the same conception of active learning. The learning material consists of two parts: instruction and interactive quizzes. 3.2.1.1 Part 1: instruction This part starts with a sthma pathophysiology . The critical factors related to asthma were described, followed by the drug mechanisms of action. Lastly, based on the drug classification, the side effects and precautions of common clinical drugs were introduced. 3.2.1.2 Part 2: interactive quizzes After Part 1, students appraised their learning outcomes through interactive quizzes. A question bank contains all the questions organized for the following three functions: the first guides the nursing students to review the asthma pathophysiology, the second strengthens the concept of pharmacological mechanisms, and the third reviews the side effects and precautions after integrating the pathophysiological and pharmacological concepts. The active learning mechanism consists of three parts, namely “explanations”, “quiz and feedback”, and “encouragement”, which is a part of the active learning cycle, as illustrated in . 1. Explanations: This is a step-by-step process covering the key concepts from the physiological mechanism to drug side effects. Pathophysiology is a chain reaction; however, drugs mainly improve pathophysiological responses through the antagonism of receptors and others. The step-by-step learning material and teacher's narration assisted nursing students to understand the mechanism of drugs. The learning material helped nursing students integrate their physiological, pathological and pharmacological knowledge. In this learning process, students were able to control the play mode (slow, quick, replay, or skip) based on their familiarity with the content. 2. Quiz and feedback: Students verified their learning achievement through narrative quizzes. For example, “how do the allergens destroy physiological mechanisms and cause abnormal states?” If the answer is correct, the active learning mechanism congratulates the student and provides feedback. However, if the answer is wrong, it provides hints and encouragement. 3. Encouragement: An exhausted question bank indicates that a student had correctly answered all the questions. This means that a student accomplished the learning task related to a particular learning goal. Students can then choose the next learning objective. During the quizzes, feedback is provided after answering each question. Students are congratulated when the answer is correct, and encouragement is provided when the answer is wrong. Timely encouragement could make students feel self-confidence and self-efficacy . This learning mechanism raised student's motivation. A part of the interactive learning materials related to drug treatment of asthma are shown in . In the design process, the interactive learning materials are integrated into the active learning mechanism. They were interactive and featured, spoken and visual and game-based learning aids (such as when a student is prompted to match a side effect with a drug when playing a game. Please see ). The interactive learning materials with the active learning mechanism were uploaded to the college's digital platform. Students could access the platform in their own time within the time limit specified by the teacher. The learning materials and interactive quizzes have no time limits. Students can increase their understanding and memorize more information through multiple viewings of the contents and unlimited number of attempts to the quizzes. 3.2.2 Cognitive load scale for digital reading of pharmacology Studying introductory pharmacology using the interactive learning materials was a new experience for the nursing students. Our goal was to understand the intrinsic and extrinsic cognitive load of the nursing students during the learning process and their learning achievement. This study developed a cognitive load scale for digital reading of pharmacology (CLSDR_P) based on the literature . According to , prequiz and postquiz results can indicate the germane cognitive load in the two groups. Therefore, we used prequiz and postquiz as the assessment of learning achievement, as well as the evaluation of germane cognitive load. 3.2.2.1 Factor analysis The items of the CLSDR_P were developed and modified based on the literature  and validated through focused discussion by the expert panel consisting of five experts. Based on the recommendations of the expert panel, the CLSDR_P was consisted of 14 items. The response options are a seven-point Likert scale (ranging from 1, “strongly agree” to 7, “strongly disagree”). We invited 200 nursing students who were taking pharmacology courses to complete the survey and conducted exploratory factor analysis to validate the factors in the cognitive load scale. To ensure the validity of the items, the items with factor loading less than 0.5 were removed from the survey. displayed the factor analysis results and revealed two factors, namely “intrinsic cognitive load” (six items) and “extrinsic cognitive load” (eight items). These factors accounted for 73.2 % of the variance. The eigenvalues of the two factors from the principal component analysis were both larger than 1, and the reliability (Cronbach's alpha) coefficients for these scales were 0.916 and 0.956, respectively, with an overall alpha of 0.947. The CLSDR_P was considered to be adequately reliable for assessing nursing student's intrinsic and extrinsic cognitive load in relation to the pharmacology interactive learning materials. 3.2.2.2 Reliability and validity In addition, we invited 50 nursing students who were taking pharmacology courses to determine reliability. Reliability was tested by internal consistency analysis. Cronbach's alpha was calculated whereby a Cronbach's alpha higher than 0.8 was considered satisfactory . The CLSDR_P had a Cronbach's alpha value of 0.922 and 0.934 for items on intrinsic and extrinsic cognitive load, respectively. The CLSER_P was also determined to be valid by a panel of five experts, including one senior pharmacist, one senior pharmacology instructor, two senior nursing instructor, and one professor of science education. It had acceptable content validity , with content validity indices (CVI) of 80.5 %. 3.2.3 Online quiz Learning achievement was evaluated through their online prequiz and online postquiz scores. The prequiz aimed to assess the students' prior knowledge of basic physiology and pathology include consisted of 50 multiple choice questions with a maximum score of 100. The postquiz was used to evaluate the nursing students' learning achievements after using the interactive learning materials. It was composed by 50 multiple choice questions with a maximum score of 100. The prequiz and postquiz were designed by the teachers who taught the introductory physiology and pharmacology course and were evaluated by three educators from related fields for expert validity.   Design of the interactive pharmacology learning materials using the active learning mechanism Learning materials play a key role in learning. The use of learning materials makes teaching easier and facilitates the learning process for students. noted that developing learning materials suited to the learning goals and that engage learners is challenging. Learning pharmacology is difficult for nursing students because of the complexity of the subject. Students must learn the mechanisms, classifications, side effects, pronunciation of each drug, and much more. Therefore, when learning materials can guide students effectively in their study, they become more engaged. In this study, we developed interactive learning materials that integrated digital technology and the active learning mechanism using interactive teaching material production software. The critical elements of the drug mechanism of action were presented step-by-step in the learning material. In this study, we presented interactive teaching materials on asthma treatment drugs as an example to demonstrate the applicability of our active learning approach while all other topics were designed on the basis of the same conception of active learning. The learning material consists of two parts: instruction and interactive quizzes. 3.2.1.1 Part 1: instruction This part starts with a sthma pathophysiology . The critical factors related to asthma were described, followed by the drug mechanisms of action. Lastly, based on the drug classification, the side effects and precautions of common clinical drugs were introduced. 3.2.1.2 Part 2: interactive quizzes After Part 1, students appraised their learning outcomes through interactive quizzes. A question bank contains all the questions organized for the following three functions: the first guides the nursing students to review the asthma pathophysiology, the second strengthens the concept of pharmacological mechanisms, and the third reviews the side effects and precautions after integrating the pathophysiological and pharmacological concepts. The active learning mechanism consists of three parts, namely “explanations”, “quiz and feedback”, and “encouragement”, which is a part of the active learning cycle, as illustrated in . 1. Explanations: This is a step-by-step process covering the key concepts from the physiological mechanism to drug side effects. Pathophysiology is a chain reaction; however, drugs mainly improve pathophysiological responses through the antagonism of receptors and others. The step-by-step learning material and teacher's narration assisted nursing students to understand the mechanism of drugs. The learning material helped nursing students integrate their physiological, pathological and pharmacological knowledge. In this learning process, students were able to control the play mode (slow, quick, replay, or skip) based on their familiarity with the content. 2. Quiz and feedback: Students verified their learning achievement through narrative quizzes. For example, “how do the allergens destroy physiological mechanisms and cause abnormal states?” If the answer is correct, the active learning mechanism congratulates the student and provides feedback. However, if the answer is wrong, it provides hints and encouragement. 3. Encouragement: An exhausted question bank indicates that a student had correctly answered all the questions. This means that a student accomplished the learning task related to a particular learning goal. Students can then choose the next learning objective. During the quizzes, feedback is provided after answering each question. Students are congratulated when the answer is correct, and encouragement is provided when the answer is wrong. Timely encouragement could make students feel self-confidence and self-efficacy . This learning mechanism raised student's motivation. A part of the interactive learning materials related to drug treatment of asthma are shown in . In the design process, the interactive learning materials are integrated into the active learning mechanism. They were interactive and featured, spoken and visual and game-based learning aids (such as when a student is prompted to match a side effect with a drug when playing a game. Please see ). The interactive learning materials with the active learning mechanism were uploaded to the college's digital platform. Students could access the platform in their own time within the time limit specified by the teacher. The learning materials and interactive quizzes have no time limits. Students can increase their understanding and memorize more information through multiple viewings of the contents and unlimited number of attempts to the quizzes.   Part 1: instruction This part starts with a sthma pathophysiology . The critical factors related to asthma were described, followed by the drug mechanisms of action. Lastly, based on the drug classification, the side effects and precautions of common clinical drugs were introduced.   Part 2: interactive quizzes After Part 1, students appraised their learning outcomes through interactive quizzes. A question bank contains all the questions organized for the following three functions: the first guides the nursing students to review the asthma pathophysiology, the second strengthens the concept of pharmacological mechanisms, and the third reviews the side effects and precautions after integrating the pathophysiological and pharmacological concepts. The active learning mechanism consists of three parts, namely “explanations”, “quiz and feedback”, and “encouragement”, which is a part of the active learning cycle, as illustrated in . 1. Explanations: This is a step-by-step process covering the key concepts from the physiological mechanism to drug side effects. Pathophysiology is a chain reaction; however, drugs mainly improve pathophysiological responses through the antagonism of receptors and others. The step-by-step learning material and teacher's narration assisted nursing students to understand the mechanism of drugs. The learning material helped nursing students integrate their physiological, pathological and pharmacological knowledge. In this learning process, students were able to control the play mode (slow, quick, replay, or skip) based on their familiarity with the content. 2. Quiz and feedback: Students verified their learning achievement through narrative quizzes. For example, “how do the allergens destroy physiological mechanisms and cause abnormal states?” If the answer is correct, the active learning mechanism congratulates the student and provides feedback. However, if the answer is wrong, it provides hints and encouragement. 3. Encouragement: An exhausted question bank indicates that a student had correctly answered all the questions. This means that a student accomplished the learning task related to a particular learning goal. Students can then choose the next learning objective. During the quizzes, feedback is provided after answering each question. Students are congratulated when the answer is correct, and encouragement is provided when the answer is wrong. Timely encouragement could make students feel self-confidence and self-efficacy . This learning mechanism raised student's motivation. A part of the interactive learning materials related to drug treatment of asthma are shown in . In the design process, the interactive learning materials are integrated into the active learning mechanism. They were interactive and featured, spoken and visual and game-based learning aids (such as when a student is prompted to match a side effect with a drug when playing a game. Please see ). The interactive learning materials with the active learning mechanism were uploaded to the college's digital platform. Students could access the platform in their own time within the time limit specified by the teacher. The learning materials and interactive quizzes have no time limits. Students can increase their understanding and memorize more information through multiple viewings of the contents and unlimited number of attempts to the quizzes.   Cognitive load scale for digital reading of pharmacology Studying introductory pharmacology using the interactive learning materials was a new experience for the nursing students. Our goal was to understand the intrinsic and extrinsic cognitive load of the nursing students during the learning process and their learning achievement. This study developed a cognitive load scale for digital reading of pharmacology (CLSDR_P) based on the literature . According to , prequiz and postquiz results can indicate the germane cognitive load in the two groups. Therefore, we used prequiz and postquiz as the assessment of learning achievement, as well as the evaluation of germane cognitive load. 3.2.2.1 Factor analysis The items of the CLSDR_P were developed and modified based on the literature  and validated through focused discussion by the expert panel consisting of five experts. Based on the recommendations of the expert panel, the CLSDR_P was consisted of 14 items. The response options are a seven-point Likert scale (ranging from 1, “strongly agree” to 7, “strongly disagree”). We invited 200 nursing students who were taking pharmacology courses to complete the survey and conducted exploratory factor analysis to validate the factors in the cognitive load scale. To ensure the validity of the items, the items with factor loading less than 0.5 were removed from the survey. displayed the factor analysis results and revealed two factors, namely “intrinsic cognitive load” (six items) and “extrinsic cognitive load” (eight items). These factors accounted for 73.2 % of the variance. The eigenvalues of the two factors from the principal component analysis were both larger than 1, and the reliability (Cronbach's alpha) coefficients for these scales were 0.916 and 0.956, respectively, with an overall alpha of 0.947. The CLSDR_P was considered to be adequately reliable for assessing nursing student's intrinsic and extrinsic cognitive load in relation to the pharmacology interactive learning materials. 3.2.2.2 Reliability and validity In addition, we invited 50 nursing students who were taking pharmacology courses to determine reliability. Reliability was tested by internal consistency analysis. Cronbach's alpha was calculated whereby a Cronbach's alpha higher than 0.8 was considered satisfactory . The CLSDR_P had a Cronbach's alpha value of 0.922 and 0.934 for items on intrinsic and extrinsic cognitive load, respectively. The CLSER_P was also determined to be valid by a panel of five experts, including one senior pharmacist, one senior pharmacology instructor, two senior nursing instructor, and one professor of science education. It had acceptable content validity , with content validity indices (CVI) of 80.5 %.   Factor analysis The items of the CLSDR_P were developed and modified based on the literature  and validated through focused discussion by the expert panel consisting of five experts. Based on the recommendations of the expert panel, the CLSDR_P was consisted of 14 items. The response options are a seven-point Likert scale (ranging from 1, “strongly agree” to 7, “strongly disagree”). We invited 200 nursing students who were taking pharmacology courses to complete the survey and conducted exploratory factor analysis to validate the factors in the cognitive load scale. To ensure the validity of the items, the items with factor loading less than 0.5 were removed from the survey. displayed the factor analysis results and revealed two factors, namely “intrinsic cognitive load” (six items) and “extrinsic cognitive load” (eight items). These factors accounted for 73.2 % of the variance. The eigenvalues of the two factors from the principal component analysis were both larger than 1, and the reliability (Cronbach's alpha) coefficients for these scales were 0.916 and 0.956, respectively, with an overall alpha of 0.947. The CLSDR_P was considered to be adequately reliable for assessing nursing student's intrinsic and extrinsic cognitive load in relation to the pharmacology interactive learning materials.   Reliability and validity In addition, we invited 50 nursing students who were taking pharmacology courses to determine reliability. Reliability was tested by internal consistency analysis. Cronbach's alpha was calculated whereby a Cronbach's alpha higher than 0.8 was considered satisfactory . The CLSDR_P had a Cronbach's alpha value of 0.922 and 0.934 for items on intrinsic and extrinsic cognitive load, respectively. The CLSER_P was also determined to be valid by a panel of five experts, including one senior pharmacist, one senior pharmacology instructor, two senior nursing instructor, and one professor of science education. It had acceptable content validity , with content validity indices (CVI) of 80.5 %.   Online quiz Learning achievement was evaluated through their online prequiz and online postquiz scores. The prequiz aimed to assess the students' prior knowledge of basic physiology and pathology include consisted of 50 multiple choice questions with a maximum score of 100. The postquiz was used to evaluate the nursing students' learning achievements after using the interactive learning materials. It was composed by 50 multiple choice questions with a maximum score of 100. The prequiz and postquiz were designed by the teachers who taught the introductory physiology and pharmacology course and were evaluated by three educators from related fields for expert validity.   Experimental procedure showed the experimental design. The experiment lasted for 6 weeks. Before the study, all nursing students had received instruction on physiology and pathology. They then completed a questionnaire to measure their cognitive load and took a prequiz. In the first week, an orientation was given to help students of the experimental group learn to use the interactive learning materials. In the second week to fifth week, students of the experimental group learned the topics including the anti-hypertensive drugs, asthma treatment drugs, peptic ulcer treatment drugs and nonnarcotic drugs using the interactive learning materials. The students of the control group studied using a traditional pharmacology textbook to learn the same topics. After the experiment, the two groups completed a questionnaire to measure their cognitive load and took a postquiz.   Ethical considerations Permission to undertake the research was obtained from National Cheng Kung University Human Research Ethics Committee, Taiwan (approval no. NCKU HREC-E-109-342-2). Prior to the research, all students were informed of the purpose of the study and the written informed consent was obtained from the students and their parents/guardians.   Data analysis SPSS 26.0 software was used to perform the statistical analysis, with an analysis of covariance (ANCOVA) used to analyze learning achievement. A factor analysis was performed to analyze the reliability of cognitive load scales. Finally, ANCOVA was used to examine the differences in intrinsic and extrinsic cognitive loads between the experimental and control groups.   Results We designed interactive pharmacology learning materials using an active learning mechanism as mentioned in the previous section. We evaluated their effects on cognitive load and learning achievement in this experiment. The following has the results. 4.1 Analysis of the intrinsic and extrinsic cognitive loads We compared the cognitive load of nursing students in the experiment and control groups. We used the same homogeneity test of regression coefficients within groups to confirm the appropriateness of ANCOVA. The assumption of homogeneity was not violated, with F = 0.005 ( p > .05) and F = 0.176 ( p > .05), respectively. Therefore, ANCOVA was employed to compare the intrinsic cognitive load and extrinsic cognitive load of the two groups. , displayed the ANCOVA results. The results revealed that the intrinsic cognitive load of the experimental group was significantly lower than that of the control group ( F = 64.6, p < .001). Similarly, the extrinsic cognitive load of the experimental group was significantly lower than that of the control group ( F = 28.9, p < .001). These results suggested that the interactive learning materials with the active learning mechanism reduced the nursing students' intrinsic and extrinsic cognitive loads. 4.2 Learning achievement We conducted a test on the homogeneity of regression coefficients within groups and found the assumption of homogeneity was not violated, with F = 0.022 ( p > .05). Hence, ANCOVA was employed to compare the learning achievements of the experimental and control groups. displayed the ANCOVA results indicating that the experimental group's quiz scores improved significantly more than those of the control group ( F = 4.71, p < .05). These results suggested that the active learning mechanism enhanced the nursing students' learning achievement.   Analysis of the intrinsic and extrinsic cognitive loads We compared the cognitive load of nursing students in the experiment and control groups. We used the same homogeneity test of regression coefficients within groups to confirm the appropriateness of ANCOVA. The assumption of homogeneity was not violated, with F = 0.005 ( p > .05) and F = 0.176 ( p > .05), respectively. Therefore, ANCOVA was employed to compare the intrinsic cognitive load and extrinsic cognitive load of the two groups. , displayed the ANCOVA results. The results revealed that the intrinsic cognitive load of the experimental group was significantly lower than that of the control group ( F = 64.6, p < .001). Similarly, the extrinsic cognitive load of the experimental group was significantly lower than that of the control group ( F = 28.9, p < .001). These results suggested that the interactive learning materials with the active learning mechanism reduced the nursing students' intrinsic and extrinsic cognitive loads.   Learning achievement We conducted a test on the homogeneity of regression coefficients within groups and found the assumption of homogeneity was not violated, with F = 0.022 ( p > .05). Hence, ANCOVA was employed to compare the learning achievements of the experimental and control groups. displayed the ANCOVA results indicating that the experimental group's quiz scores improved significantly more than those of the control group ( F = 4.71, p < .05). These results suggested that the active learning mechanism enhanced the nursing students' learning achievement.   Discussion The application of digital technology in teaching is an inevitable trend in the modern education environment, regardless of the technology of digital learning materials or application of digital platforms. We developed interactive digital learning materials that integrated an active learning mechanism using current technology in this study. We expected that interactive digital learning materials will not increase cognitive load in digital learning and can enhance learning achievement. The research results revealed that the proposed approach could improve the students' learning achievement and decreased the cognitive load in comparison with the control group under the traditional learning. Many studies have demonstrated that a primary cause of medication-related errors was due to insufficient knowledge of pharmacology during nursing studies , raising concerns about the pharmacological knowledge of registered nurses . In recent years, many studies had focused on nursing student's learning about pharmacology; however, most had focused on practice, such as through online learning, blended learning, problem-based learning, and cooperative learning . Active learning strategies had been widely used in pharmacology education seminars, workshops, and conferences. However, students were not willing to spend the time on pre-class preparation required to succeed in an active learning environment because they have other courses to study . In the present study, we incorporated active learning strategies to design interactive learning materials on a digital learning platform. We hoped these learning materials would help nursing students studying pharmacology as successful as possible through condensed content and quizzes. Our findings were consistent with those of ; they reported that their multi-display learning materials significantly reduced cognitive load and enhanced learning effectiveness in 120 college students. Our findings were also consistent with another study reporting that the use of multiple teaching systems based on virtual reality could help students learn about Chinese folk performances more effectively and efficiently . Another study also revealed that the implementation of technology significantly increased the effectiveness of project-based learning and helped students identify their own abilities and interests . Thus, integrated multimedia learning materials facilitated learning. The interactive learning materials provided students with condensed content that they could learn by themselves before class as well as guided and encouraged them to study through the active learning mechanism. In this study, the design idea of the interactive materials was similar to and who claimed that design and presentation of learning materials should reflect the considerable limitations of the human information processing system. In the multimedia learning design process, consideration had been placed on the management of cognitive load . Their results are consistent with our finding. Our active learning approach yielded improvements in terms of postquiz performance and cognitive load. In our opinion, we have designed concise and easy-to-understand teaching materials based on the principles of visual, auditory, interesting, and self-controllable to reduce the cognitive load of students using these interactive materials to learn pharmacology. Instructional design should consider the cognitive processing of individuals, thus lowering the likelihood of memory overload in the learning process. We believe that cognitive load was crucial for the design of multimedia learning materials. As mentioned previously, interactive digital learning materials incorporated with active learning mechanism contribute to learning pharmacology more efficiently among nursing students. However, making interactive digital learning materials that integrate active learning mechanisms requires a lot of time and efforts from instructors. It could be a challenge in promoting such innovative teaching in colleges. Our study has some limitations. First, the experiment was conducted in one junior nursing college, and the findings may thus not applicable to other nursing colleges or universities. Second, we did not compensate students in the control group. In the future, similar to a crossover design, we can alternate the control and experimental groups midway through the study to ensure that all students have the same quality of education.   Conclusion This article presented a new practical approach to teach pharmacology to nursing students. This approach is distinctive in its “explanation,” “quiz and feedback,” and “encouragement” design features. Follow-up studies should consider nursing students' perceptions of learning pharmacology and their motivation to learn before versus after using the active learning–based interactive learning materials. Other nursing educators are also welcome to use the cognitive load scale devised in this study, a scale indicating the cognitive load on students when they read digital materials. Future studies may refine this instrument or generate related findings to help improve learning effectiveness and efficiency.   Shuenn-Jiun Yiin: conceptualization, methodology, data collection, visualization, writing - review and editing. Chi-Liang Chern: visualization, writing - review and editing.   None.   