FACTSHEET: Salami Slicing | ELSEVIER | eSupport for Research | RPE02: L-08 | 2022 | Dr. Akash Bhoi
Based on eSupport for Research's video on YouTube. If you like this content, support the original creators by watching, liking and subscribing to their content.
Salami slicing is the fragmentation of one meaningful study into multiple smaller papers to increase publication output.
Briefing
Salami slicing is the practice of breaking one meaningful study into multiple smaller papers to increase publication counts, and it’s generally considered unethical because it fragments evidence, delays access for readers, and burdens editors and reviewers. Unlike duplicate publication—where the same data are reported in two or more publications—salami slicing involves segmenting a larger study into “slices,” each presented as a separate manuscript.
A key guideline is that slices should not be published in a way that misleads readers or inflates the apparent breadth of findings. As a general rule, if the slices share the same hypothesis, population, and methods, splitting the study is not acceptable. The practice can also distort the literature by making different papers appear to come from different subjects or samples when they actually derive from the same underlying dataset. Beyond ethics, it creates practical problems: it can delay when the full results become available to readers and forces journals to spend additional time evaluating multiple related manuscripts.
Salami slicing must also be distinguished from legitimate reuse of parts of a study. In some cases, large datasets—such as data from certain clinical trials or epidemiological studies—may not be fully publishable. When only limited reporting is possible, overlapping or partial use of data may occur, but it still needs careful handling to avoid presenting the same results as if they were wholly independent.
There are also circumstances where multiple publications from a single study can be legitimate. If different manuscripts address different questions and use unrelated endpoints, authors may describe the importance and outcomes separately. In that scenario, the work should function more like independent studies that happen to draw from a larger project. Even then, each paper should clearly define its own hypothesis and be presented as a section of a broader study rather than as unrelated standalone research.
Transparency is the central safeguard. Journals typically expect authors to disclose whether a submitted manuscript represents fragmented data from a larger study. Authors should provide information about any closely related manuscripts—whether recently published, under submission, or already accepted—by sending copies to the publisher or editor during submission. With that disclosure, editors can decide whether the submission is genuine segmentation for distinct questions or an inappropriate form of salami slicing. If it’s deemed improper, the manuscript can be handled accordingly before peer review proceeds.
In short: salami slicing means slicing one study into multiple papers to multiply outputs, and when slices share the same core hypothesis, population, and methods, the result is usually unethical. Proper disclosure and clear separation of distinct research questions are what determine whether multiple papers are acceptable or a misleading fragmentation of evidence.
Cornell Notes
Salami slicing is the fragmentation of one meaningful study into multiple smaller publications, often to increase the number of papers. It differs from duplicate publication: duplicate publication repeats the same data across papers, while salami slicing segments a larger study into “slices.” When slices share the same hypothesis, population, and methods, the practice is generally considered unethical because it can mislead readers, distort the literature, delay full access to results, and add workload for editors and reviewers. Multiple papers can be legitimate when they address genuinely different questions with unrelated endpoints, but each manuscript must clearly define its own hypothesis and be presented as part of a larger study. Transparency—submitting related manuscripts and disclosing fragmentation to editors—is the key requirement for ethical handling.
How does salami slicing differ from duplicate publication?
Why is salami slicing generally considered unethical?
What does “distortion of the literature” mean in this context?
When can multiple publications from one dataset be legitimate?
What transparency steps are expected when submitting potentially fragmented manuscripts?
Review Questions
- What specific features (hypothesis, population, methods, endpoints) determine whether splitting a study is likely to be considered salami slicing or a legitimate set of separate analyses?
- How should authors handle disclosure when a manuscript is part of a larger study with overlapping or related submissions?
- What harms does salami slicing create for readers and for the editorial and peer-review process?
Key Points
- 1
Salami slicing is the fragmentation of one meaningful study into multiple smaller papers to increase publication output.
- 2
Duplicate publication repeats the same data across papers, while salami slicing segments a larger study into different manuscripts.
- 3
If slices share the same hypothesis, population, and methods, salami slicing is generally considered unethical.
- 4
Salami slicing can mislead readers by making papers seem to come from different subjects or samples, distorting the literature.
- 5
Fragmentation can delay full access to results and increases workload for editors and reviewers.
- 6
Multiple papers can be acceptable when they address genuinely different questions with unrelated endpoints, with each manuscript clearly stating its own hypothesis.
- 7
Ethical handling depends on transparency: disclose fragmentation and submit copies of closely related manuscripts (published, submitted, or accepted) to editors.