The Dunning-Kruger effect is a cognitive bias that was first described in a 1999 paper by David Dunning and Justin Kruger. In it, they described the results of several studies where individuals who scored low on various measures of cognitive ability tended to overestimate their knowledge or skill in a particular domain, while those who scored higher on these cognitive tasks tended to estimate a much lower knowledge or skill level. The authors noted that “this overestimation occurs, in part, because people who are unskilled in these domains suffer a dual burden: Not only do these people reach erroneous conclusions and make unfortunate choices, but their incompetence robs them of the metacognitive ability to realize it” (1999). Thus, the more you know, the more you realize you don’t know.
This observation has been challenged somewhat in the scientific literature, but their idea has resonated in popular culture and has been applied across a multitude of domains. The most common way to see this represented is as a U-shaped graph with ‘confidence’ on the X-axis and ‘Knowledge’ on the Y-axis—a relationship that is so potent that once you are aware of it, you start to see it everywhere from climate change denialists to anti-vaxxers.
Nowhere is this effect more prevalent than in issues regarding health. I have often been astonished by some of the statements that I have seen on Facebook or on certain fringe news sites that exude an abundance of confidence but represent a fundamental misunderstanding of even the most basic aspects of the science. The issue is then self-reinforcing because viewers with low health literacy subsequently regurgitate this information with equal zeal, while people with significantly more scientific knowledge are forced to couch their rebuttals with citations and caveats because they have an understanding of how complicated the topic actually is. Anyone who has ever been sucked into a social media flame war or been called on to correct a family member’s misinformation has experienced the marked difference between the energy required to explain a complicated topic and the ease of someone who can reject that conclusion with their ‘gut’.
This cognitive bias towards oversimplicity leading to overconfidence is especially dangerous in the time of COVID-19. Discussions about masks reducing inhaled oxygen or hydroxychloroquine as a panacea that seem to refuse to die on the internet actually cause tangible harm if left unaddressed. It is part of the duty of healthcare professionals to correct misinformation that could lead to harm despite how exhausting it may be. It’s the responsibility of those on the right side of the Dunning-Kruger graph to educate those on the left.
Kruger, J., & Dunning, D. (1999). Unskilled and unaware of it: How difficulties in recognizing one’s own incompetence lead to inflated self-assessments. Journal of Personality and Social Psychology, 77(6), 1121–1134. https://doi.org/10.1037/0022-3518.104.22.1681