#KeyLIMEPodcast 148: The Flipped Classroom – What is the evidence? [KeyLIME Live! @ICRE, Part 1]

Coming to you from ICRE 2017, our first of two parts of KeyLIME Live where we were joined by co-hosts Glenn Regehr and Karen Hauer. Up first is Karen’s selection, which  explores a hot topic in medical education: The Flipped Classroom (FC). This systematic review examines the evidence for the FC as a pedagogical strategy in medical education.

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KeyLIME Session 148 – Article under review:

Listen to the podcast

View/download the abstract here.


Chen F, Lui AM, Martinelli SM. A systematic review of the effectiveness of flipped classrooms in medical education. Medical Education.  2017. 51(6):585-597.

Reviewer:  Karen Hauer


The Flipped Classroom (FC) is a hot topic in medical education, and in education overall. What is a FC?  Many of us think first of a video lecture, but that is only part of the story. A flipped classroom involves reversing the usual sequence of activities in traditional classrooms, where the students first hear a lecture and then go home to do homework that might involve solving problems or studying the content further.  In a flipped classroom, the learner watches the lecture first at home, and then uses class time to engage in some sort of interactive learning activity to apply the knowledge learned in the lecture. This systematic review examines the evidence for the FC as a pedagogical strategy in medical education.


To determine (1) the scope of studies published on FCs in medical education, (2) the quality of the studies that have been published on FCs in medical education and (3) the effects of the FC, as reported in controlled trials.

Type of Paper

Systematic review

Key Points on Methods

Ethics approval was not required.

  • Used appropriate databases; English language only
  • Did not use google scholar, grey literature, meeting abstracts
  • Focused on FC in medical education across the continuum: UME, GME, CME.
  • Does not say who conducted the search. Provided the search terms, and worked with a health science librarian
  • 2 authors screened all articles based on title and abstract, according to criteria provided in Table 1; worked independently; kept any articles for which they disagreed about relevance. This yielded 82 articles.
  • Then the same 2 authors reviewed each of these 82 articles in detail using a protocol that included learner level, type of study design, and impact using Kirkpatrick’s hierarchy, which organizes outcomes on a scale from perceptions and satisfaction to impact on learning to impact on a larger system.
  • Then they examined the studies that used a controlled design more closely, because these had the most rigorous study design. They again resolved discrepancies through discussion.
  • No mention of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines although they seem to have followed the recommended steps

Key Outcomes

They identified 118 unique articles for review, they reviewed the full text of 82 articles, and ended up with 46 articles included that met their criteria. There is a nice flow chart in Figure 1 for the literature search results in the format of a PRISMA flow diagram

Results focus on the 46 studies that met all inclusion criteria. These studies focused mostly on medical students, with 19 focused specifically on preclerkship or clerkship students, 11 on residents and fellows. Some were more general, like commentaries, without a specific learner level. None focused on CME.

Nine articles used a controlled study design, and these were examined more closely in the results.

  • 4 studies used a controlled before and after design, examining pre-post for an intervention group who used the FC and a control group who had traditional lectures. As the authors state, this allows for both within-group and between-group comparisons controlling for prior knowledge
  • The other 5 controlled studies compared FC to a traditional lecture format but didn’t collect baseline data on the participants

Major findings about impact of FC:

  • First, people like it. Studies with students generally show that students like the FC and that it can make them more enthusiastic about a specialty and improve task value and enjoyment. One study in radiology showed they are less bored in a FC.
  • Second, the effect on knowledge and skills is unclear. The 9 controlled studies examined the impact on knowledge and skills and found mixed results. In the 4 studies that reported effect sizes, the median effect size was very small at 0.08. Furthermore, confidence intervals crossed zero, meaning that it’s not clear whether there even was a significant positive effect.
  • Authors raise the good point that most studies did not report compliance with the intervention or control, meaning that we don’t know whether the learners actually participated in the FC or traditional lecture.

Key Conclusions

 The authors conclude…

  • The FC is gaining popularity in medical education, with most studies being done with medical students
  • The benefits of FC are unclear
  • Learners seem to like the FC, but more studies are needed to show whether or not it improves learning

This systematic review raises questions in the study of the FC

  • Should studies aim to show equivalency or improvement in learning? If learning is equivalent but learners like the FC better, is that enough? Is it worth the effort to create that video of a lecture?
  • This article doesn’t tell us much about what is happening in the classroom that is flipped. This is a key part of the FC model – the classroom activity needs to be well designed and carefully facilitated. Educators need to know more about how to design these in class activities to be high yield for our students and residents.
  • How to measure impact of FC on learning? Need more than short term measures of knowledge recall. What we really want to know is long term retention and application of knowledge in the clinical setting. Potential benefits of FC really do make sense from what we know from the learning sciences about how people learn – participating actively with the material, collaborating with peers and a teacher, manipulating and applying the material all should promote deeper understanding and retention
  • Would be great to see future studies that use a rigorous controlled design to examine use of the FC across an educational program, not just a course or clerkship, and measure long term impacts on learning and how learners use that information in clinical practice

Spare Keys – other take home points for clinician educators

  • Learners like the FC
  • Based on the available evidence in medical education, the jury is still out regarding whether the FC is better than traditional lectures for learning, although based on what we know about how people learn and retain knowledge, there is reason to think the FC would be better.
  • This study raises challenges for educators studying the flipped classroom or similar interventions. First, it emphasizes the importance of rigorous study design; it’s hard to do RCTs in medical education but they can give us a lot of information. Second, we need to decide when we study a new model like the FC – are we aiming with research to show that it’s equivalent, or that it’s better? Is it enough to show equivalence and that learners like it better?
  • This is not a how to guide for designing a FC. This article doesn’t tell us much about what is happening in the classroom that is flipped. The key part of the FC model is that the classroom activity needs to be well designed and carefully facilitated. This points out a limitation in this study, that it’s only focused on medical education and doesn’t draw on the broader education literature. Educators would need to turn to other resources to learn how to design a FC, including the in-class activity. From a research perspective, studies that examine the design of these in class activities could tell us more about how to make them high yield for our students and residents, and what really works.

Shout out

Shout out to these authors for taking on this systematic review and helping to set a research agenda for clinician educators going forward on this important topic.

This is a nice example of a well done systematic review that summarizes what we know so far about the FC and sets a research agenda for medical educators.

Also the first author is a co-author on another recent publication, a multicenter trial of a FC intervention for anesthesia residents. This is exciting and the type of research that is needed to generate more info about the potential benefits of the FC in med ed.

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