Figures represent an extremely important, yet often overlooked, aspect of a scientific paper. Figures are often one of the first things that a reader sees when deciding whether to read a paper, and they have the power to convey much more information per square inch than text. Many of you have likely noticed that PubMed provides thumbnail images of the figures from many papers along with the abstract.
True fraud is rare, but journals may question other changes made to your figures
Because of the weight that figures carry, they are scrutinized carefully by editors and reviewers to ensure that they have not been manipulated to hide or falsify data. As a result, many journals are implementing steps to check submitted figures for evidence of tampering.
Unfortunately, while true fraud is rare, some completely harmless changes to a figure file can appear fraudulent to the journal. It is therefore important to understand what to avoid when manipulating images. Here, we offer a few suggestions, largely patterned around the Journal of Cell Biology's industry-leading standards for defining improper image manipulation.
The Journal of Cell Biology's guidelines state: No specific feature within an image may be enhanced, obscured, moved, removed, or introduced. The grouping of images from different parts of the same gel, or from different gels, fields, or exposures must be made explicit by the arrangement of the figure (e.g., using dividing lines) and in the text of the figure legend. Adjustments of brightness, contrast, or color balance are acceptable if they are applied to the whole image and as long as they do not obscure or eliminate any information present in the original. Nonlinear adjustments (e.g., changes to gamma settings) must be disclosed in the figure legend.
Some changes are obvious fraud (deleting one portion of an image or copying an image and passing it off as multiple figures), but other manipulations are more subtle.
7 things to consider when altering figures for publication:
- Always have the original, unaltered file available in case the journal requests it. If you cannot produce the original file, the journal will likely reject your submission. You should also be able to explain exactly what alterations were made to the image (i.e., the software and particular tools used).
- If you supervise any other researchers who have the ability to alter images or figures before submission, make sure they are aware of which types of image manipulation are acceptable and which are not.
- In general, it is appropriate to adjust the brightness, balance, or contrast, but only if the entire image is adjusted equally. Each pixel should be adjusted linearly.
- All bands or features evident in the original image must still be visible; do not adjust the image to the point where some parts of it disappear.
- If you have multiple images (e.g., a control cell and a treated cell), make sure that the brightness and contrast are equal for both. Changes to one panel of a figure but not another can be misleading.
- Removing some background fuzziness is acceptable, but do not remove so much that the background becomes white. At this point, reviewers may wonder if faint bands or other features disappeared, too.
- Never combine multiple images into one field. It is acceptable to splice out one lane of a gel if the information in that lane is no longer relevant. However, a black or white line should clearly indicate where the gel has been spliced.
For more information, see Rossner and Yamada (2004).
Knowing the rules saves time and hassle.
In the first two years of testing for image manipulation, JCB editors found that 25% of manuscripts submitted contained figures that were manipulated in ways that could be construed as misconduct. However, only 1% of cases were actually fraud; most were resolved by providing the original file.
Being aware of what is acceptable and what is not can help you avoid the hassle of defending your work, even when you didn't carry out any fraud.
Did you know that AJE offers Figure Services to help you design or format your figures for publication? To learn how AJE can reformat your figures to fit a specific journal's guidelines or create custom figures, visit our website.
Have questions about what could be construed as improper image manipulation? Send us an e-mail.