Can (or should) text from a study protocol be reused when preparing a manuscript for submission to an academic journal?

Question

In an attempt to follow best practices in open sciences, I drafted, published, and shared a protocol for a systematic literature review. I have since completed the data collection and extraction process of the review, and I am now moving into the data analysis and manuscript preparation for submission to an academic journal.

To what extent can text from a public (open science foundation, OSF) protocol be reused (with significant modification) when drafting a new manuscript for submission to an academic journal? This is most applicable to the abstract, introduction, and methods. All of these sections will be modified and expanded upon, but I do like the phrasing of certain sentences and organization of the paragraphs.

For example, imagine the two following paragraphs:

Original

Cats are generally known to have four legs. It has also been observed that cats have fur. Cats come in all shapes and sizes, but are generally between 7 and 14 pounds and stand between 8 and 14 inches.

Modified

Cats are generally known to have four legs. However, outside events may render the cats with fewer legs. While most cats have fur, specific breeds of hairless cats are known to exist. The shapes and sizes of cats have been thoroughly studied. Garfield et al. found that cats weigh in between 7 and 14, whereas a population study by Pussinboots found that most cats stand between 8 and 14 inches.

I have found some peer-reviewed commentary on this issue here, although I understand it may be a journal-to-journal issue.

Answer 1

Quick answer: there should be no problem at all.

More details: There are three potential issues involved, none of which is usually a serious problem:

• Plagiarism: If you (or your coauthors) are the author of the original protocol, then there is no plagiarism involved. But see the next point…
• Multiple submission (often misleadingly called "self-plagiarism"): A journal will always require that you submit original work to them. It is considered a serious ethical violation to submit the same work to two different publications while pretending that the second work is completely original. But this is very easily resolved in your case. There is no problem as long as you take care of two things: the second work (your entire final journal article) should add significantly more original material relative to the first. This is no problem in your scenario. Second, you must absolutely explicitly explain the entire situation in the cover letter when you submit the journal article for consideration for publication. Give the full citation to the original protocol and summarize the differences between the protocol and the full final article. As long as you do these two things, no editor should have any problem.
• Copyright violation: This concern comes into play if you signed over the copyright of the protocol when you published it. If you did not, then there is no concern here; you can redo anything you want with it with a new journal article. However, if you did sign over copyright, then check the original protocol publisher's terms in the copyright assignment form that you signed. Almost always, such forms permit republication or extensive borrowing of your own work as long as you explicitly cite the original publication. Thus, this is rarely a problem. And if you are not sure whether you signed over copyright or not, ask all your coauthors. If no one signed anything, then the copyright remains with the authors. The publisher must explicitly get you to sign something, or else they do not automatically get your copyright.

Answer 2

Surely you can reuse any source (whether public or not), and you have to cite the original and quote the parts you use verbatim. If you don't cite or don't quote properly, it would be plagiarism or a violation of copyright or both.

Whether your modifications together with the remainder of your manuscript have so much value that they justify the acceptance of your submission is a completely different question.