I keep on answering the same types of questions on Twitter, so here is a handy Frequently Asked Questions page where I answer the most common ones.
Do you find these cases by eye?
Q: How do you find those cases of image duplications that you write about or post on Twitter? Do you use software or find them by eye?
A: I find these by just looking at them. I don’t use any software to find them; I just flip through PDFs. I do use Mac’s Preview to make an image darker or lighter to bring out some details, if needed. Occasionally, I make use of FotoForensics.com or Forensically to confirm my suspicions, but I always find them by eye first. Preview is also used to “decorate” the image with colored boxes to point out the areas that look similar to each other.
Why don’t you name and shame?
Q: Why do you not post a link to the papers that contain the images with duplications that you post on Twitter? I want to know which paper these photos were published in. Name and Shame!
A: I usually do not post links to those papers for several reasons. First, on Twitter, that will quickly evolve into making fun of the authors or institutions. Twitter being Twitter means that this could turn nasty very quickly. Secondly, I would rather not be sued for defamation. These types of posts are about raising awareness to the types of problems present in the scientific literature, not to make fun of the authors. Some exceptions might apply.
Isn’t there any software that can do this?
Q: Someone should develop software to find these things. Software is going to be much better than the human eye.
A: I agree, and several groups are working hard on that. I have shared a dataset of 400 papers with image problems and 800 matched controls in which I did not find any problems with several teams that are developing such software. I have not heard back from any of them, so I assume this is much harder than most people assume. But this is only a matter of time. In fact, Daniel Acuna from Syracuse University has written authored this promising study (bioRxiv, 2018).
I do not believe you. You are not an expert.
Q: I really don’t see these duplications. I do not believe you can find these cases of image duplications. All gels / western blots look similar, so how many false positives do you call? Did you write any scientific papers about science misconduct?
A: Well, after scanning 20,000 papers for our 2016 study, and probably another 20,000 after that, I can tell you that most images indeed are unique. But I also developed a good feeling for which ones are not. Together with other authors, I wrote three scientific papers about this work. Here they are:
- In our 2016 mBio study, my co-authors Ferric Fang and Arturo Casadevall and I describe a dataset of 20,000 biomedical papers with photographic images. I scanned all of these and found about 800 of them (4%) to contain inappropriately duplicated images. The paper describes the types of duplications (simple, shifted, and manipulated) and some stats related to journal impact factor and country of affiliations. We hypothesized that about half of the problems identified by us might be caused by an intention-to-mislead.
- In a 2019 follow-up paper, we looked at the risk factors associated with these three types of duplications, and found that academic culture and monetary incentives were among the factors that played a big role.
- We also focused on one particular journal, Molecular and Cellular Biology, and looked at a set of 960 papers published in MCB. This study was published in 2018. About 6% of these contained duplicated images, and we followed those papers to see what the reasons were behind that. About 10% of these were retracted.
You should write a book about this.
Q: Why don’t you write a book about this? I would buy it.
A: That would cost me months, and I would feel it slows me down too much. For now, I would rather focus on finding and reporting more of these cases, and on educating peer reviewers and editors on how to find errors and misconduct before papers get published. But if you want to help me write a book, please let me know!
Can you check a paper for me?
Q: I suspect there is image duplication in a particular paper or by a particular group. Could you please check?
A: Absolutely. Send me an email at elies bik at gmail period com. It helps if you send me the PDF, and not let me guess which paper or author you mean. I might not find anything, but if I do, I might post this on PubPeer. I will honor any request for anonymity, and not share your name, unless you want me to.