You might have seen or heard people engaged in debates about evolution, climate change, GMOs, vaccinations, or any other popular science-oriented issue refer to peer- reviewed literature, published papers, or journal articles. These all refer to the same thing. So what is the big deal about peer-reviewed science literature, and why do some people keep harping on this as if it were the main standard for truth and integrity? Isn’t a scientific paper in a journal the same thing as a magazine article or an op-ed piece in the newspaper, or even a post on Facebook?
No, it’s not. Papers are the currency and lifeblood of science. They are what count. Speeches, lectures, presentations at prestigious meetings, articles in magazines, interviews on TV, blog posts and books are nice, but a scientist is judged by his or her publication record, first and foremost
It takes anywhere from three weeks to three months to write a paper. A good scientific paper can be as short as a page (like Watson and Crick’s announcement of the double helix structure of DNA), or as long as most of an issue of a journal (like the announcements of the human genome sequence). The number of authors can be one (pretty rare these days) to in the hundreds. Most papers (like most books) are not very important and are read by only a small number of people, usually colleagues in the same field as the topic of the paper. A small minority are read by hundreds. Almost no one who isn’t a scientist ever reads a scientific paper.
All papers share certain features. They are written in the passive voice. I use the passive voice a lot (“they are written in the passive voice”, being an example), which has gotten me in trouble when I write other stuff. The style is very particular, and not found in other kinds of writing. One way to describe it is extreme low key. One never uses phrases like “we have discovered”, or “we now prove that”, but instead things like “These results are consistent with the concept that humans and chimps evolved from a common ancestor”, which is about as strong a statement as you are likely to see.
What makes a scientific paper special is the fact that in order to get published it must be peer reviewed. When the paper is finished, the author sends it to a journal. The editor assigns the manuscript to two or more professional scientists who are working in the same field as the topic of the paper. These reviewers then read the manuscript and decide if the paper is good enough to be published. Papers can be rejected (fairly common for the top rated journals), accepted as is (very rare) or sent back to the author with suggestions for changes or questions that need to be answered. The comments (all of which must be addressed) can be minor or can require months of more experimental work.
After the author resubmits the revised manuscript, the whole process repeats, with the same reviewers judging the new version of the paper. From the time the paper is first submitted until the final accepted version is published, anywhere from a few months to over a year can go by. Reviewers generally do not get paid for their time or efforts in reviewing papers. It’s just considered to be part of the job of being a scientist.
When you read a paper in Science, Nature, the Proc. of the National Acad. Sciences, or any other journal, you know that that paper has been carefully and thoroughly checked by other scientists and has passed a stringent review. Of course the process is not perfect. Some reviewers miss things, and sometimes a bad paper gets through. But it usually works well, and the entire system of science relies on the proper functioning of the peer review approach.
There have been suggestions that scientists publish their work online, without peer review. This is a very bad idea. It’s also a very bad idea to trust anything scientific you might read on a website or a blog post (this one of course being an exception) unless there are citations to published peer reviewed papers included. Statements like “Many scientists have found that GMOs cause negative effects on human health” are meaningless. Statements like “Vaccination has been proven safe in numerous studies (References 1-10)” can be taken seriously, as long as one checks the references to see if the poster is telling the truth. (I have seen many statements where the referenced papers said the opposite of what was reported in the post.)
The peer review system is the best way we know to ensure honesty, quality, integrity and accuracy in reports of scientific findings. Without it, we would revert to the days when those who yelled the loudest or seemed the most sincere would prevail in the battlegrounds of ideas. The web can, at its worst, encourage that backward direction, and all the more reason for people to be careful and rely on peer-reviewed papers for truth in science.