Analysis of Alternative Strategies for the Teaching of Difficult Threshold Concepts in Large Undergraduate Medicine and Science Classes

Introduction: Threshold concepts have a transformative effect on student understanding and are often difficult or ‘troublesome’. Students in undergraduate Medicine and Science must understand many threshold concepts, but are often presented with these ideas in large introductory classes with limited individual assistance. Effective approaches for the teaching of threshold concepts have not been evaluated in this context. Methods: Students in two large introductory Medicine and Science classes at the University of New South Wales (UNSW) were taught a genetics threshold concept (the Hardy-Weinberg law) using a lecture-based simulation, small group tutorials, computer simulation and a variety of learning resources. Student knowledge of the concept was then assessed using a test and an examination. A survey and exploratory factor analysis were used to assess student responses to the different teaching methods. Results: Factor and survey response analysis showed that students in both Medicine and Science were divided in their preference for either small group tutorials or lecture-based simulations when learning difficult concepts. Medicine students showed a stronger preference for tutorials than Science students, and a proportion of Medicine students were anti-simulation. In contrast, Science students were more likely to report that the simulation improved their understanding. Students used all of the learning resources provided, but few students preferred computer simulation. Conclusion: Students in large Science and Medicine classes are polarised in their preferences for the teaching of difficult threshold concepts. This suggests that introductory courses will only effectively teach difficult concepts if they use a variety of teaching approaches. This has important implications for course design and resourcing and provides a foundation for the improved teaching of threshold concepts in undergraduate Medicine and Science.