Q: Can I use the content of my earlier published article in my thesis?
I submitted a paper to Cancer Medicine in open access 3 years ago. If I submit this OA paper (to the university) as a thesis now, won’t that be considered as duplicate submission?
You have mentioned that you had submitted your paper to a journal 3 years ago, but not mentioned whether it was published. My answer is based on the assumption that the paper was published.
It is quite common to reuse the contents of a published article in a thesis. This is a perfectly acceptable practice as long as you mention in the beginning that the thesis is based on a published article and provide the link to the article. If you make this disclosure, it will not be considered duplicate submission.
However, remember that a thesis and a journal article are two very different genres of writing and, therefore, you will have to modify the journal article and rewrite it in the form of a thesis.
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