Thanks Mohamed for your answer. I did not submit a paper to multiple journals. I asked the question from the standpoint of a peer reviewer.

Hi Emeka

It is my belief that you have the ethical duty to convey to the editor yhat the new paper that you are reviewing bears a striking resemblance to an earlier work reviewed. It might even be worth mentioningmentioning if the previous paper was accepted. Perhaps the revelation might affect the acceptance but you would have served the wider academic community by ensuring that the same paper does not get published in multiple outlets without due caveat. 

IMO:  you are undertaking reviews for two different 'clients' (the journals).  If the article did not fit with the first journal, then this may not be the case with the second, so IMO you should review it.  If the article had flaws that caused it to be rejected by the first journal, then the authors may have attempted to address these in the new submission (in which case they should again be entitled to your expert opinion).  

More commonly though, it may be that they are just taking a punt at a new target to get the work published.  If there are still the same 'errors' or issues, then I would imagine that your review will be similar to the previous one  ;-)  

Either way, as a reviewer you can easily contact the editor as you see fit.  If the authors have made an attempt to improve the work, then I would not refer to any previous view. If the work is still seriously flawed, I would contact the editor & ask if having seen a previous version of the work (you do not have to say where), if they would still like you to provide a review.  I am sure your reviews are based on simple fact, and would not be influenced by personal opinion, so you would be commenting on the work in front of you, not the process that led to it being there. Either way, I think that if we put ourselves forward as peer-reviewers, we should respond as quickly & fairly as possible.

Hi Emeka,

Yes you should say if you have been previously asked to review the paper in for another journal.  Two reasons; one someone may be trying incorrectly to make multiple submissions of the same paper. Two from the reviewers perspective properly reviewing a paper takes a long time and most reviewers will try to write constructive comments to improve the paper if they don't reject it.  If the author/s did not take on-board your comments the first time around why should you, the reviewer, bother to write another set of comments.  However if you do send your original comments out a second time it is only fair that the editor of the second journal knows what has happened should the author/s query the response.

Sometimes you may be asked to review a paper which you reviewed for another journal, the authors did take on board your comments but decided in light of the changes required that another journal might be more suitable.  Since this will now be your second review of the paper if you choose to do it you may comment on the review in a different way, building on what has or hasn't been improved, from that which you would have done had it been the first time around.  Again the editor of the second journal need to know so that they understand why you have commented as you have.

The author/s may be quite correct in their assumption that the second journal is a much better home for their paper, so it isn't a problem, just a matter of transparency.

Caroline

Ethically no two different journals should publish one paper. since it is known to you that a paper has been submitted to another  journal it just but proper to let the later journal be aware of the situation. the only exception is where there is an evidence that the paper has been withdrawn from the first jounal

Thanks very much for your insightful answers. I will wait for other researchers to  add their answers or comments before I say more.

Before doing any action, we have to made careful check to be sure that there is no difference between the two articles and the previous one was accepted for publication...

In case the difference is not significant we can tell the editor that we have previously reviewed an article and there is significant similarity with the new one, then ask him to check (via private communication with the editor of the other journal) whether the previous article was accepted or not.

Agree with Loay, it depends. It's not clear what was the result of your (first) peer review. If you suggested the editors the acceptance of the article, then you should check with editors about their intentions to publish a paper. If your peer review was not positive, then  "second try" is somehow expected from authors.

Your question also raises an importance of the feedback from the editors, after peer review process ends. Usually the reviewer is not informed about other reviewers opinions and editor's final decision.

Thanks Emeka for this good question. Many authors submit their papers to multiple journals at the same time to increase the opportunity of acceptance of their papers because some Journals take a long time to send back reviews to authors and the reviews can be negative with insufficient justifications.  I think to reduce these practices, journals should reduce the time of reviewing papers.

Thanks everyone for your answers. As Jadranka rightly said, reviewers are not always told the outcome of the papers they reviewed. I don't think this is right. Mournir, thanks for your comment. I think that authors should check very well before submitting their papers. One of my papers took about one year or so to have it reviewed and re-reviewed in the same journal. The painful thing is that it was rejected after re-review because one of the three reviews did not like the paper.  

Dear Emeka,

It is my point as an author considering your standpoint as reviewer. Of course, in this case for instance, if I followed the ethical publication rules of the first journal to ensure the multiple publication in particular; the editor of the journal then rejected my paper because of its quality. Based on the review and rejection points of the first submission and following the publication requirements of the second journal, the paper refinement was then carried out to improve its quality.

The assumption is that you peer reviewed the same paper earlier for the second journal, why you inform to the editor if the paper was improved? I agree with the contextual dependence from Loay and Jadranka's opinions and also with Caroline around the transparency issue.  

Dear A'ang,

Thanks for your answer.

I would certainly refuse to review such a paper, if I can confirm that it was plagiarized.  And I wouldn't hesitate to inform the editor, if I have proof.)

(Emeka, I have a related question. Earlier I wrote a paper (4 names), and sent it to a journal. Both reviewers said that it should be improved in suggested ways, and re-submitted.

But 2 of the persons didn't contribute, and we removed them, and put in 2 new names (RG colleagues who contributed). But we changed the TITLE, and 80% of the content, added a FIGURE and increased the tables from 3 to 6. Now when I send back to the journal, it has to be a new article, right? Partly because it has a new title.  But I can just inform the editor about the 'history of the article' in the cover letter? What do you think?)

I think it is almost a new article based on the fact that its content is 80% new. You should inform the editor about the development. Even if you did not, the reviewers will alert him.

I will approach this situation from a perspective of an honest author who wrote a good quality paper.

In my opinion, the reviewer should tell the editor that he or she has reviewed this same paper before and inform the editor about the recommendation ("accept" or "reject").  And perhaps decline to act as the reviewer this time around. 

Assume that the paper was rejected by a previous journal. Many journals now demand that the authors suggests up to 5 reviewers. So the author might have appointed you as the reviewer again because of your expertise (and his or her trust in your good judgement). The author would not know who reviewed the paper because of the reviewers' anonymity. So they might recommend you if they resubmit the rejected paper to another journal. Of course, if they know who rejected the paper they will not appoint the same person again and vice versa. :--)

So, to be fair I think it would be the most appropriate course of action for the reviewer to inform the editor and perhaps not to act as the reviewer for the same paper.. 

Thanks Larisa for your answer.

I as an editor would certainly enjoy being informed about the fact that you have been asked twice to peer review the same article. If it is the same. Sending the same article to several journals simultaneously, but at the end published in only one of them, causes editors and reviewers a lot of extra work for nothing. I would also like to know whether the author significantly improved the article. Or simply copy-paste it. It tells a lot about how responsive to reviewer's and editor's suggestions the author might be. Not in negative way of course. After all, I assume we are all after improvement.

Thanks Tomaz for your comment.

I would review the paper as a new article unless if the authors did not review the article based on my initial comments in which case I will reject it as in the previous journal.

Thanks Dr Anthony for your answer.

I think you have an obligation, ethically speaking, to bring that to the attention of the editor. To do otherwise is to do a disservice to scholarship. But I don't think you should necessarily decline reviewing the paper. Let the editor sort the matter out with the author(s) and get back to you.

Many thanks Nelson for your answer.

If you inform the editor of a journal that you have reviewed the same (?) paper previously, this would suggest that the paper has been rejected elsewhere, presuming the paper was not submitted to more than one journal contemporaneously.

If the paper is the same, or is essentially unchanged, you can submit the earlier report to the more recent journal.