Oops!… I Did It Again. When to correct or retract?

How many image duplications in a paper would be acceptable? If the paper has two identical photos that represent different experiments, and the authors’ reply is: ‘Oops, we uploaded the wrong photo’, that would be acceptable. Mistakes happen, and the authors can correct the error by sending in an erratum with the correct photo(s). But should editors be equally forgiving in the case of two cases of “Oops, we made a mistake”, or other, more complicated scenarios?

Let’s take a look at different types and numbers of duplications. As I explained in two previous blog posts (here and here), there are three categories of image duplications.

  • Category I duplications: simple, identical duplications.
  • Category II duplications: duplications involving shift, rotation, or a flip.
  • Category III duplications: parts within the same panel are duplicated or parts from other panels are duplicated into another panel.

Category I is the most likely to be the result of an honest error, while Category III is really hard to explain by an honest error and the most likely to be done intentionally.

We can probably all agree that a paper with just one Category I duplication can be addressed with a simple correction or erratum. But how about papers with multiple duplications? Or, to sing along with Britney Spears, the “Oops! I did it again”, cases?

Let’s take a look at some different, real-life examples in order of increasing severity of error. Where would you draw the line as a journal editor presented with these concerns? Which paper could get away with a correction, and which paper should be retracted? There is no clear answer, so this post is meant as a discussion starter, not as a solution.

Two instances of type I duplications

Here is a figure with two duplications, marked in orange and pink. Note that the pink boxes represent different experiments but the same protein, while the orange boxes represent different experiment and different proteins. Should a paper with not just one, but two type I duplications be corrected, or retracted?

Two type I duplications within a single figure. Source: https://pubpeer.com/publications/7CE738CC0FB797AB86CC8BE8463B7A

A single type II duplication

Here is a figure that has one type II duplication. The lanes marked in red appear to look very similar, suggesting that both actin panels are derived from the same blot, while the lanes represent different time points. Should a paper with this figure-of-concern be addressed with a correction or a retraction? Assume this is the only problem with this paper.Could this be an honest error or was this done with the intention-to-mislead? There is no clear answer here, so we might give the authors the benefit of the doubt and ask for a correction, if this was the only problem with a paper.

Two instances of type II duplications

Here is another set of duplications below. In this case, there are two sets of type II duplications within the same figure. Should a paper that contains this figure, with 2 pairs of shifted duplications, be corrected or retracted?

Two type II duplications within a single figure. Source: https://pubpeer.com/publications/7CE738CC0FB797AB86CC8BE8463B7A

Combinations of type I and II duplications

In this example, a single figure had a type I duplication and a type II duplication within the same figure. The authors admitted they uploaded the wrong panels – twice. How would you respond to this? Would you consider both of these errors, one of which involved a 180 degrees rotation to be correctable, or do you think there might have been an intention to mislead? There is no clear answer here.

Two duplications within the same figure. The one marked in red is a type I duplication, while the blue-boxed panels denote a type II duplication involving a 180 degree rotation. Taken from: https://pubpeer.com/publications/ED1F35595C9CE803CAC4E92E64E683

This paper has three figures that combined show two simple duplications (albeit of different exposure, marked in pink and pale purple) and multiple shifted duplications (marked in light and dark orange). If you are a journal editor, would you accept the excuse of an author that they made some mistakes while assembling or uploading the figure, or would you retract this paper?

Two type I duplications and several type II duplications within the same paper. Source:

Type III duplications

In my opinion, a type III duplication should almost always lead to a retraction. Here are some examples. It is really hard to imagine that the duplications in the images below occurred in the Western blots, flow cytometry plot, or microscopy photo by accident.

Two sets of type III duplications within a figure. See: https://pubpeer.com/publications/DF7ED70F2EC41AFF0775881425EA23
Multiple cases of Type III duplications within a single figure. Some parts of the panels (shown in boxes of the same color) appear to be duplicated between panels while other parts are unique. See: https://pubpeer.com/publications/3823967D4947674E9BDF3B0C219BF5
Microscopy panels that appear to have several type III duplications. Taken from: https://pubpeer.com/publications/0ACA63AC48C60852962E58844828A4

Where would you draw the line?

There are lots of examples on PubPeer where the authors replied that they made a mistake. But after saying “Oops, another mistake” too many times, the other data in a paper become unreliable as well, and it becomes more and more likely that the mistakes were not done as the result of an honest error. But where does one draw the line? How many times can one say “Oops, I did it again”? How many mistakes can be addressed with a correction? At which point should an editor make the decision to retract the paper?

Again, I do not have a clear answer, but it is good to think about some threshold or flowchart.

Here is a proposal, meant to start the discussion, not to end it:

  • A single category I or II duplication might be addressed with a correction
  • Two cases of a category I duplication within the same paper might be addressed with a correction
  • Two category II duplications within the same paper should be retracted
  • Any combination of multiple category I/II duplications should be retracted
  • Any paper with a category III duplication should be retracted

Let me know what you think in the comments below.

5 thoughts on “Oops!… I Did It Again. When to correct or retract?”

  1. Nice post and I generally just wanted to say that I really appreciate all the good you are doing!

    In terms of retract vs correct, I think there is also some room for responsiveness. I am not sure if I can imagine multiples of any of these errors happening innocently, but perhaps if lead/corresponding authors respond quickly with corrections even papers with I+II or II+II could avoid an automatic retraction. (quick response as evidence of non-guilty conscience?)

    If academia is really publishing 2.5 million scientific papers per year then that means the clumsiest 0.01% still account for 250 papers annually, maybe plenty of room for accidental replication+rotation?

    2.5 million source: http://blog.cdnsciencepub.com/21st-century-science-overload/ (lazy googling)


  2. I agree with you that it may likely be impossible to draw a fair line. Each instance depends on technical issues of image preparation and the consequences it has for the main findings of the paper. On the other hand, a clear line may also help in making sure people pay more attention: we know from other areas how pernicious some incentives are we have in science. Why not use this to our advantage? A simple line of >1 and the paper is out, may lead to people quadruple-checking their work before submission and making sure fewer errors of sloppiness or haste are committed?


  3. Interesting piece!

    Personally I would like to see more liberal use of ‘flagged’ for category I and II. When the choice is between correct vs retract, the onus is on the journal to make a judgement call on the intent of the authors (malicious or not).

    Saying that a paper has duplicate images is virtually undebatable and puts the editor on a much surer footing. This also lets the reader their own judgement about the data, and shifts the responsibility to the authors to do something about it.

    Type III on the other hand….. Retract with minimal discussion! I simply can’t see any way in which these kind of images could occur without either malice or extreme incompetence, either of which should call the entire manuscript into question.


  4. This book explains PI s don’t enter labs . See and hear Prof Jeffrey Hall’s Nobel Prize lecture. At the about 38th -40th minute in his lecture he explains about PI’s and what they do. He says not all PIs investigate


    The Rise of the Scientist-Bureaucrat
    Survival Guide for Researchers in the 21st Century

    Authors: Perez Velazquez, Jose Luis


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s