Naomi M. Sell, MD, MHS, and Denise W. Gee, MD, FACS
February 1, 2019
Traditional teaching techniques may elicit images of a lecture in front of a chalkboard. In the life of an exhausted surgical resident, however, sitting in a chair and listening to a monotonous voice for an hour is more likely an invitation for sleep rather than an educational experience.
How, then, do we keep our residents and medical students engaged during didactics?
Multimedia learning not only keeps a listening audience engaged but results in better recall of the material presented.1 Multimedia education is the combination of words and graphics to promote learning. Examples include slideshow presentations, captioned videos, or handheld simulation devices. The utilization of multimedia, most often through programs such as PowerPoint
The ability to retain and recall information has been described in two theories: Dual Coding and Cognitive Load.
Dual Coding was described by Paivio et al. in 1971 and theorizes that our brains process information through two separate channels: a visual channel and a verbal channel.5 Each pathway is processed separately; however, studies have shown that information presented to both systems concurrently, as in multimedia presentations, has a higher likelihood of recall later.
Cognitive load refers to the amount of mental effort a learner requires to learn a topic. There are intrinsic and extrinsic sources of cognitive load.6 Intrinsic is the difficulty of the content in the lecture while extrinsic is the way the information is presented. We may not be able to control the difficulty of the content, but we can control how it is presented so that we can optimize it in a way that enhances learning.
With these two theories in mind, how do we best format our multimedia presentations for maximal resident benefit? Richard Mayer, PhD, has been a leader in the field of education theory and multimedia learning.7 His studies have illustrated key principles that will best serve our residents and students.
Advances in technology have allowed for many audio and visual components to be incorporated in multimedia presentations. Unfortunately, not all charts or graphics are equally effective at promoting learning. Mayer describes 12 key principles for multimedia learning and how to best present content with the use of media agents.8 Studies of students have shown that PowerPoint presentations that utilize the following principles have better content retention rates and understanding of content:3
Despite the plethora of PowerPoint guidelines available across the internet, there is actual, tested, empirical evidence of best techniques for retention and learning from multimedia presentations.9 Studies have tested elements of slide design—font, size, text color and text layout—to determine the optimal display of information. This has been tested by looking at speed of reading the slide, recall time, and visual fatigue. Here we will explain optimal multimedia ergonomics and give insight into best techniques for your own didactic presentations.
There are two principal font types: serif and sans serif. A serif is a line attached at the end of a stroke in a letter or symbol. Serif style fonts that include these edges include Times New Roman and Georgia. Sans serif fonts do not incorporate this extra stroke and include Arial and Helvetica. Serif font is ideal for PowerPoint as the edges at the bottom of each letter help guide the eye along the line of text.10 Serif fonts have been proven to be more legible and allow for increased reading speed.11
The size attributed to text is the angle of perception from the eye. In multimedia, it is important that the font is large enough for everyone to see. Small fonts restrict those seated at a distance from being able to read the content. Additionally, smaller fonts can make it tempting to cram too much information on a slide. The minimum font size that should be used is size 22.12
The scheme refers to the color of the text and how it relates to the color of the background. There are two different types: positive polarity and negative polarity. Positive polarity refers to dark text on a light background, while negative polarity is light text on a dark background. Research has shown that proofreading and word search is improved for positive polarity. Studies also measured physiologic signs of effort (including heart rate, breathing rate, skin conductance, eye strain) and found that these signs are decreased with positive polarity.13 Most importantly, study participants prefer positive polarity. Scientifically, this makes sense as a bright (white) background closes the iris of the eye more thus decreasing the effort of the lens. On the other hand, a dark (black) background does not reflex the iris to close as much and the text may, instead, appear slightly imperfect or fuzzy.13
Utilizing a bullet list format is ideal. This allows the presenter to highlight key principles and break the content into a structure easier for a learner’s mind to categorize and recall. Lists should ideally be kept to 3–5 items. When possible, try to keep each bullet point succinct to a single line.14
By combining the multimedia principles and ergonomics listed above, it might just be possible to hold our residents’ attention for an hour and help give them maximum ability to recall information when the time comes for the ABSITE.
Naomi M. Sell, MD, MHS, is a resident physician in the department of surgery at Massachusetts General Hospital, Boston, MA.
Denise W. Gee, MD, FACS, is an assistant professor of surgery in the department of surgery at Massachusetts General Hospital, Boston, MA.