Scientific journals trade in the currency of knowledge and ideas. JGIM’s commitment
to readers (and therefore our expectation of authors) is that material published in
the journal is original. But what does it mean for a piece of work to be “original?”
Certainly all scientific writing has an intellectual heritage; even Newton stood on
the shoulders of giants. Yet even in the best of circumstances, the provenance of
an idea may not be readily discernable from the reference list. And circumstances
are not always ideal.
Recently, it came to the attention of JGIM’s editors that a manuscript just published
online in another journal (Article B) bore a clear resemblance to a manuscript published
in JGIM approximately six months earlier (Article A). On closer inspection, there
was reason for concern. Both papers reported on a quasi-experimental evaluation of
a quality improvement intervention. The titles, by-lines, and abstracts were similar
and the methods sections almost identical. Moreover, entire paragraphs of the introduction
and discussion sections were almost the same.
Had an editorial crime been committed? And if so, was this a felony, a misdemeanor,
or merely a technical breech akin to jaywalking? The first job of an editor in such
circumstances is to establish the facts. Careful comparison of the two published papers
showed that the same intervention was introduced (and evaluated) in two discrete inpatient
settings: one involving housestaff, the other not. Furthermore, the patient populations,
study designs, and analytic methods were distinct.
What then, to make of a case where the same authors publish two papers using many
of the same words to report on two similar but distinct interventions? What is self-plagiarism
and how is it defined (if it exists at all)? To answer this question, we turned to
the Committee on Publication Ethics (http://publicationethics.org) and the World Association
of Medical Editors (www.wame.org), among other resources. Within hours of submitting
the redacted case to the WAME listserv, we received a number of helpful replies, including
one from Miguel Roig of St. Johns University. In prior writings, Roig has argued that
self-plagiarism exists in four forms. Duplicate publication is publishing the same
results in more than one article. Salami science is slicing up one large study into
multiple small articles. Copyright infringement consists of using previously published
material without permission of the copyright holder (which in JGIM’s case is the Society
of General Internal Medicine). Text recycling is reusing phrases, sentences, or paragraphs
found in previous work without appropriate attribution, including quotation marks.
Each of these violations carries different moral weight. Duplicate publication is
a clear ethical breech, in part because systematic reviews or meta-analyses may inadvertently
count the same data twice, leading to mis-estimation of effects that could potentially
harm patients. Salami science is undesirable but may be unavoidable without changes
in the ways universities assess faculty research productivity (i.e., by counting papers).
Copyright infringement is a legal issue, and interestingly, there have been few if
any successful lawsuits involving this form of self-plagiarism. Finally, text recycling
is a matter of degree. In our informal poll, many experts (including Roig) are fine
with around 10% re-cycling of verbiage, some even arguing for the benefits of repeating
complex methods verbatim. A few suggested limits of 15-20%, but none countenanced
more than 30%.
JGIM has no established limit for acceptable text re-cycling, nor do we currently
plan to impose one. However, the JGIM editors wish to be clear about two things. First,
we expect that authors will disclose any substantial overlap between manuscripts submitted
to JGIM and all other manuscripts published, submitted, or nearing submission. Often,
the easiest way to disclose is simply to provide a copy of the other manuscript(s).
Second, authors should be careful about the amount of text they recycle. While there
are sometimes good reasons for re-using certain textual elements (particularly in
the Methods and literature review), authors should be cautious and thoughtful in doing
so. JGIM readers expect that work appearing in the journal is original. Small deviations
can be tolerated. Bigger ones may give the appearance of deception and should be eschewed.