The “Effect” Paper Mill

While working on the larger “Tadpole” and “Stock Photo” paper set, plenty of other papers with similar title and layout structure were found that appeared to belong to different sets.

In this post, I will present to you the “Effect” paper set, uncovered by super-spotter Hoya Camphorifolia (a pseudonym).

I called this set the “Effect” set because about half of the papers’ titles start with “Effect of” or “Effects of”.

As with other paper sets suspected of being produced by a paper mill, this group of papers are all authored by different research groups at different hospitals, studying different animal models and therapeutics. Yet, they all share at least one image with each other.

The Effect paper set is small – currently only 11 papers [links to Excel spreadsheet – PDF – Image Gallery]. Although small in size, it is a good set to show how paper mills produce papers with the same figures and sell these to multiple authors. While each paper looks plausible by itself, only looking at the complete set will reveal that almost all of the figures in these papers appear in other papers as well.

All credits for uncovering this paper mill go to Hoya Camphorifolia, who did an amazing job discovering the connections between these papers. Independently, I found several of these papers myself, only to discover that Hoya had posted them 2 weeks earlier on PubPeer 🙂

All papers were published in the same journal, the European Review for Medical and Pharmacological Sciences. It is the same journal that published 113 of the 121 Stock Photo papers and several of the Tadpole papers.

Image Gallery

The images (re)used in these papers are mainly photos of heart tissues and Tunel (apoptosis) assays. I often give each of these photos a name, which helps me to better recognize them. Here is a link to the Image Gallery [PDF].

For example, one of the recurrent images of heart tissue reminded me of a rolled up bath towel. Of course, feel free to see something else in it. Maybe you see a bunch of burritos, or a plate full of profiteroles? Whatever makes sense to you!

Image “Towel” occurred in three of the papers. Here are the three Towels next to each other. Although they differ slightly in color tint and zoom factor, these photos clearly look very similar to each other. Also note that they represent very different experiments in each of these papers.

Image “Waves” also was found in three papers. Here are the three occurrences next to each other.

One particular photo of lung tissue looked like Peter and the Wolf to me, with the wolf on the right and a boy with messy hair on the left. It was found in three papers in this set.

I labeled the TUNEL photos just TN1-TN2-TN3, shown here respectively in red, yellow, and blue. Here are the figures from four different papers in which these panels were found:

There were some recurring Western blots too. Here are two examples of the blot that I called “WB1”:

Once each recurring photo has a name, the papers that contain that photo can be labeled with a “1” in the column with that photo in the spreadsheet of this set of papers. That way, it becomes more clear that each of these photos was used in at least two papers, and that each paper has at least one of the photos in this set.

Spot another “Effect” paper? Let me know.

All 11 papers have been reported to the Editorial Office of the journal, as well as on PubPeer [links to Excel spreadsheet – PDF – Image Gallery].

If you happen to spot another paper that is not part of the list yet, let me know in the comments, and I will add it to the spreadsheet.