Peer review does not mean we can trust a published paper
May 3, 2013
“The benefit of published work is that if they have passed the muster of peer review future researchers can have faith in the results”, writes a commenter at The Economist. Such statements are commonplace.
I couldn’t disagree more. Nothing is more fatal to the scientific endeavour than having “faith” in a previously published result — as the string of failed replications in oncology and in social psychology is showing. See also the trivial but crucial spreadsheet error in the economics paper that underlies many austerity policies.
Studies have shown that peer-reviewers on average spend about 2-3 hours in evaluating a paper that’s been sent their way. There is simply no way for even an expert to judge in that time whether a paper is correct: the best they can do is say “this looks legitimate, the authors seem to have gone about things the right way”.
Now that is a useful thing to be able to say, for sure. Peer review is important as a stamp of serious intent. But it’s a long way from a mark of reliability, and enormous damage is done by the widespread assumption that it means more than it does.
Remember: “has passed peer review” only really means “two experts have looked at this for a couple of hours, and didn’t see anything obviously wrong in it”.
Note. I initially wrote this as a comment on a pretty good article about open access at The Economist. That article is not perfect, but it’s essentially correct, and it makes me happy that these issues are now mainstream enough that it’s no longer a surprise when they’re covered by as mainstream an outlet as The Economist.