Levels of scientific evidence

For those of us whose memories of science classes are fuzzy at best, the credibility of “evidence” backing up information we encounter online can be difficult to discern. It is easy to mistake weak evidence for strong evidence. Bad actors can exploit this unfamiliarity to trick us into believing mis- and disinformation. That’s why we need to recognize that all evidence is not created equal.

News reports and opinion pieces about scientific topics might cite a mix of different kinds of evidence so you will need to understand those types, including expert opinions, lab findings and research studies. We created this infographic with Dr. Katrine Wallace (Dr. Kat), an epidemiologist and assistant professor at the University of Illinois at Chicago, to help you determine the quality of the evidence presented to support a claim. Refer to the pyramid to evaluate the quality of evidence of a claim you encounter that’s a bit of a head-scratcher.

Click here to download the infographic (PDF).