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University of Houston: Why breaking up research studies does more harm than good

The process of breaking up research is dangerous one, according to UH's Big Idea. Graphic byMiguel Tovar/University of Houston

Salami slicing, breaking a paper on a single study up into smaller “slices” and publishing them in more than one journal, is broadly discouraged and considered unethical. Why does the practice persist? What do PIs believe are the benefits of doing it?

Two problems

Breaking up research into smaller slices can have serious consequences for scientific integrity. Researchers, especially younger researchers, may get used to looking at data in smaller pieces and not as a whole. This is dangerous from an academic perspective as valuable conclusions, that could have been derived if the data were presented as a whole, are overlooked.

Further, salami slicing of data may do more harm than good to a researcher’s career over time because it significantly reduces their chances of publishing in high impact journals, thereby lessening the weight of their accrued body of work.

One reason salami slicing still persists, is that there is a veritable avalanche of papers vying for publication. And the number seems to be steadily increasing.

“The academic market became more competitive after the nation’s economic downturn, in 2008,” said Rodica Damian, UH associate professor of psychology. “We saw a lot of competition between those with Ph.D.s and those who were conducting postdoc research. Before, you needed a postdoc if you were in Biology, for instance – but you didn’t need one if you had a doctorate in Psychology. That is no longer the case.”

Another reason salami slicing might persist is that advisors may suggest to a graduate student that they write a series of simpler papers as opposed to a more complex paper consisting of multiple measurements. A researcher might get these “single-lens papers” published much more quickly than their multi-faceted counterparts, due to the amount of background research the journal’s editors need to do on the more complicated papers.

How to avoid self-plagiarism

Salami slicing is not necessarily self-plagiarism, but often the practice does feature a large amount of “text overlap,” according to Miguel Roig, Ph.D. on the website of the Office of Research Integrity for the U.S. Department of Health and Human Services. One example Roig gives is as follows:

“Several months ago, for example, we received a manuscript describing a controlled intervention in a birthing center. The authors sent the results on the mothers to us, and the results on the infants to another journal. The two outcomes would have more appropriately been reported together…The important point is that readers need to be made aware that the data being reported were collected in the context of a larger study.”

The Big Idea

An article published by the NIH suggests this rule of thumb: “If the ‘slice’ of the study in question tests a different hypothesis as opposed to the larger study or has a distinct methodology or populations being studied, then it is acceptable to publish it separately.”

However, when a colleague is trying to do a meta analysis, they need to know what your study actually measured. “One thing you can do to avoid salami slicing,” said Damian, “is to pre-register all the projects you’re planning to do from a specific data set. Then ask yourself, do they use different hypotheses, measures, literatures, etc.”

After all is said and done, are they substantively methodically different research papers? If so, they can be sent to different, separate journals.


This article originally appeared on the University of Houston's The Big Idea. Sarah Hill, the author of this piece, is the communications manager for the UH Division of Research.

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Building Houston


Baylor College of Medicine's Lillie and Roy Cullen Tower is set to open in 2026. Rendering courtesy of BCM

Baylor College of Medicine has collected $100 million toward its $150 million fundraising goal for the college’s planned Lillie and Roy Cullen Tower.

The $100 million in gifts include:

  • A total of $30 million from The Cullen Foundation, The Cullen Trust for Health Care, and The Cullen Trust for Higher Education.
  • $12 million from the DeBakey Medical Foundation
  • $10 million from the Huffington Foundation
  • More than $45 million from members of Baylor’s Board of Trustees and other community donors, including the M.D. Anderson Foundation, the Albert and Margaret Alkek Foundation, and The Elkins Foundation.

“The Cullen Trust for Health Care is very honored to support this building along with The Cullen Foundation and The Cullen Trust for Higher Education,” Cullen Geiselman Muse, chair of The Cullen Trust for Health Care, says in a news release. “We cannot wait to see what new beginnings will come from inside the Lillie and Roy Cullen Tower.”

The Baylor campus is next to Texas Medical Center’s Helix Park, a 37-acre project. Rendering courtesy of BCM

The Lillie and Roy Cullen Tower is set to open in 2026. The 503,000-square-foot tower is the first phase of Baylor’s planned Health Sciences Park, an 800,000-square-foot project that will feature medical education and research adjacent to patient care at Baylor Medicine and Baylor St. Luke’s Medical Center on the McNair Campus.

The Baylor campus is next to Texas Medical Center’s Helix Park, a 37-acre project that will support healthcare, life sciences, and business ventures. Baylor is the anchor tenant in the first building being constructed at Helix Park.

“To really change the future of health, we need a space that facilitates the future,” says Dr. Paul Klotman, president, CEO, and executive dean of Baylor. “We need to have a great building to recruit great talent. Having a place where our clinical programs are located, where our data scientists are, next to a biotech development center, and having our medical students all integrated into that environment will allow them to be ready in the future for where healthcare is going.”

In the 1940s, Lillie and Roy Cullen and the M.D. Anderson Foundation were instrumental in establishing the Texas Medical Center, which is now the world’s largest medical complex.

“Baylor is the place it is today because of philanthropy,” Klotman says. “The Cullen family, the M.D. Anderson Foundation, and the Albert and Margaret Alkek Foundation have been some of Baylor’s most devoted champions, which has enabled Baylor to mold generations of exceptional health sciences professionals. It is fitting that history is repeating itself with support for this state-of-the-art education building.”

The Cullen Foundation donated $30 million to the project. Rendering courtesy of BCM

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