This is an important and difficult issue. 'Self-plagiarism' and 'salami slicing' however are often conflated.

I once had a colleague who published EXACTLY the same article -- word for word -- in two different journals (only with different titles). This is a case of flagrant plagiarism. (She was discovered, forced to see the Vice Chancellor, and asked to leave.)

However, suppose you merely copy a paragraph, or a few lines here and there (or a table)? I'd suggest that *as long as you wrote them* this would be OK. After all, if you have said something clearly and precisely -- and it seems the best way to say it -- why the requirement to paraphrase yourself just for the sake of it? I think we would all own up to this kind of self-plagiarism.

This kind of plagiarism is a matter of degree, and at some point a boundary line of respectable authorship is crossed and it becomes "wrong". (It's a bit like spanking I suppose: a little seems OK, but a lot seems kinky and undeserved. Justified corporal punishment can quickly cross over into sadism.)

That's *self-plagarism*. We might call this "same writing--same writing".

"Salami-slicing" is a different matter entirely. That's taking a body of data one has acquired and making several papers out of it (i.e., writing different papers using the same qualitative or quantitative information/evidence/empirical observations but where the writing is different. Perhaps it even involves different authors).

We might call this "same data, different writing". Hence: 'Slicing' the data to meet different audiences/journal requirements.

This seems to me to be a legitimate academic strategy for increasingly one's publication output -- as long, of course, as one does not -- at the same time -- self-plagarise beyond an 'acceptable' degree! (If one did, that would be a case of same writing/data---same writing/data"-- and that *would* clearly be unacceptable).

It seems that the author(s) were guilty of self-plagiarism and this paper should be rejected. In some cases it makes sense to use the same table twice: e.g. in case your questionnaire is 5 pages long, you cannot use responses to all questions in one paper, so you can write several and you may wish to publish the same table about the respondents' average age, education etc. Still, in this case you should cite this table and also ask from the publisher of your previous paper if they allow you to use it. Also, if you use some text from your previous paper(s), you also have to cite it, and some publishers have rules about how many words you can take from your previous paper(s) without asking for permission. It is also not fine to rewrite your sentences a bit without citing them.

I believe that self plagiarism can be accepted in part, but should be avoided, for example, in texts from different publishers.

Self plagiarism is a result of the pressure that researchers struggle to publish, even if we do not have good texts for publication.

Yes - good posts. Self-plagiarism is quite a complex issue - and its never straight-forward. Copyrights laws are also often complex, convoluted and 'unenforceable'. There is obviously as difference between salami-sclicing and submitting the same manuscript to several publishers and that, to a certain extent, adds more legitimacy to salami-sclicing; it's seen as a 'lesser evil' and, perhaps, almost tolerated.

I agree that warning the editor is probably the best course of action. It's then up the the journal and the publishing house to decide what is acceptable for them.

This is an important and difficult issue. 'Self-plagiarism' and 'salami slicing' however are often conflated.

I once had a colleague who published EXACTLY the same article -- word for word -- in two different journals (only with different titles). This is a case of flagrant plagiarism. (She was discovered, forced to see the Vice Chancellor, and asked to leave.)

However, suppose you merely copy a paragraph, or a few lines here and there (or a table)? I'd suggest that *as long as you wrote them* this would be OK. After all, if you have said something clearly and precisely -- and it seems the best way to say it -- why the requirement to paraphrase yourself just for the sake of it? I think we would all own up to this kind of self-plagiarism.

This kind of plagiarism is a matter of degree, and at some point a boundary line of respectable authorship is crossed and it becomes "wrong". (It's a bit like spanking I suppose: a little seems OK, but a lot seems kinky and undeserved. Justified corporal punishment can quickly cross over into sadism.)

That's *self-plagarism*. We might call this "same writing--same writing".

"Salami-slicing" is a different matter entirely. That's taking a body of data one has acquired and making several papers out of it (i.e., writing different papers using the same qualitative or quantitative information/evidence/empirical observations but where the writing is different. Perhaps it even involves different authors).

We might call this "same data, different writing". Hence: 'Slicing' the data to meet different audiences/journal requirements.

This seems to me to be a legitimate academic strategy for increasingly one's publication output -- as long, of course, as one does not -- at the same time -- self-plagarise beyond an 'acceptable' degree! (If one did, that would be a case of same writing/data---same writing/data"-- and that *would* clearly be unacceptable).

Publishing the same study twice is yet another product of the half-witted publish or perish fanaticism that grips higher education and research. Why else would anyone want to do it? This pernicious culture has undermined quality research, encouraged plagiarism of all types and set potential research collaborators up as rivals rather than colleagues. Self plagiarism is a spectacular example of the obsession with numbers of publications over the quality of them.

In the case I am referring to it was a half-witted 'academic'. I doubt there is much of that behaviour going on, but I take your point.

Martin and Barry,

Yes - there is pressure to publish but, hopefully, most want to be recognised for the quality of their publications; and their originality. The academic who was asked to leave was foolish - but usually anti-plagiarism policy works in the favour of the individual. Its easy to say 'oh I didn't realise' - or 'I didn't feel well enough supported/trained by the institution. Seems a bit harsh to that extent unless they had been warned previously.

Correct Martin - salami-slicing is different bits from a study but then, to me a full and complex PhD thesis needs several publications - not one i.e potentially a publication per one or two chapters. I still think that people see salami-slicing more commonly though as essentially the same whole study mainly repeated - but in a different journal. Of course - the worst scenario which occurs every now and then is passing someone else's work off as your own - but changing a bit and/or submitting in obscure journals where you hope that no-one will notice.

Dean: "The same study repeated but in a different journal"? If by this you mean the same "write up" then this is the same as what my former colleague did. This is beyond the pail, and unambiguously wrong of course--whether or not it is in obscure journals.

"Salami slicing" as I see it is where the body of data (call it "A") is written up as quite different papers reaching slightly different conclusions, and perhaps having different aims, so A1, A2, A3...etc., where 1,2,3 are different "write ups". That seems OK to me--if a bit boring.

It was Rutherford, I think who claimed that "There are two kinds of disciplines: Physics (he meant Philosophy of Physics) and stamp collecting". Most sciences, e.g., Biology, apply the same theoretical paradigm (Darwinism) to different organisms, birds, fish, bugs. That's "stamp collecting" according to Rutherford. But "real" science is the pathbreaking developments of revolutionary science: Newtonianism giving way to Einstein's views, quantum theory, etc. Not many of us do the latter.

Most of us are "stamp collectors", and most of us "salami slice", but there is a place for that in most disciplines.

Yes most PhDs need to have a few papers in them. But whether they are "slices" or whether they each contribute some brand new thesis or argument is a debatable point. I'd say the latter would be unlikely, except in the case of exceptionally talented individuals.

Good response Martin - but you've misinterpreted the first part. Every now and then in some of our leading journals (especially out of China) - authors will submit an exact (bar a few words maybe) 'other' study - as their own. That's the height of plagiarism to me and, in fact, its outright theft and fraud - but it happens.

Yes - Salami-slicing can appear boring - and I have been guilty of it myself in my earlier career. That said, if citation is to go by, one article can be equally as popular as the next - so maybe it can be more about 'spreading the message around' to different groups in different ways - who may not, otherwise, have had access to the 'one original'.

Yep. Accept both of those points.

It is motive that determines plagiarism rather than article content. It may in some circumstances be acceptable, even advisable to include work that the author has published previously.

One example of this would be a new interpretation of older data or a different application of it to a newly identified problem. In such cases it would not be salami-slicing but simply using already existing data or method. There is no problem with this if the author is honest. A reference back to the original work places the data or method in a new context and as such it is deserving of being a new publication.

Where the motive is honest it is not self-plagiarism to re-use old data.

As for Rutherford and 'stamp collecting', what a supreme example of intellectual brilliance being unaccompanied by common sense!

Dear David, I think by far the most important thing is that you turn over the results of your discovery to the journal's editor(s). As far as the same subjects and the same table describing them and even a high degree of overlap in describing the methods, I think this has become pretty common and largely acceptable, if perhaps a bit lazy. The standard article does not allow us to publish all possible results from one study, nor frankly, as others have suggested, is it necessarily in our own best interests to try. If the data in our study warrant it, we are better served to slice up the findings of our study and distribute it across various publications. As far as using some of the exact same words, indeed this probably does violate the copyright of the journal in which the first article is published, no one seems to be bothering about that, although obviously the safer thing would be to rewrite rather than use the exact words. Now, in your case, it sounds like some of the same results are being published twice without a clear statement that these are previously published results. This is where, in my opinion, there is a departure from commonly accepted practice and a likely violation of both journal and institutional policies against duplicative publications. I have been involved directly as a reviewer with two of these and handled them just at the journal level, where in agreement with the editor we did not contact the authors' institutions and I am aware of a third case with a colleague who received manuscripts from two very high-rank journals with largely the same findings, where both journals rejected the manuscripts. I hope this helps. Bob