Slides lead to lower retention
And, yes, they are boring
However, this study also addressed the belief that, when using slides, the slides themselves are not the problem. If people knew how to use slideware properly, this argument goes, there wouldn’t be a problem. “PowerPoint doesn’t bore people,” these folks often say. “Using PowerPoint poorly is what bores people.”
Not true. The Barcelona study demonstrated that eliminating slides improves both average and good presenters. In this particular study, while one professor’s students scored higher overall than the other—i.e. one lecturer was a better presenter than the other—the students of both professors who saw slides scored significantly lower than those who didn’t.
The Barcelona study was conducted with a base of two-hundred-and-five students registered in a course entitled “The Psychology of Education.” This was a compulsory course for those working toward a bachelor’s degree in psychology.
Students were divided into four streams led by two professors. On different days, each professor taught one stream of students in the morning and one in the afternoon. For this study, each professor used slides for one class and a blackboard for the other.
The professors worked together to develop a nineteen-slide, forty-minute presentation for the class in which slides would be shown—fairly “standard” slides that all of us have seen more times than we can count. They also prepared a ten-question multiple-choice quiz to evaluate the knowledge students acquired from the lecture. The test was administered immediately after each of the four lectures and based solely on information taught during class.
Students who didn’t see slides scored twenty-two per cent higher on the quiz than those who did. By simply shutting off the projector, communication effectiveness can be enhanced by twenty-two per cent (and that’s without implementing a single additional idea from One Bucket at a Time).