As long as the required information is present (cover letter, title page, abstract, references, CONSORT diagram for randomized studies, protocol for randomized and interventional trials, etc.), the ...

Authors should provide a cover letter that explains 'in their words' why the new work should be published in a top-tier journal. Often we receive manuscripts submitted with a brief cover letter ...

In accordance with the Uniform Requirements, however, manuscripts containing only SI units will not be returned for that reason. Though cover letters are not required, the NEJM Online Submission ...

All manuscript files, including the cover letter. In virtually all cases, referee comments to the author for this and all previous versions of the manuscript, but only if the manuscript was peer ...