Abstract The article itself is an abstract (of a paper or presentation) that usually has been presented or published separately.
Announcement Material announced in the publication (may or may not be directly related to the publication)
Article Commentary A work whose subject or focus is another article or articles; this article comments on the other article(s). (This value would be used when the editors of a publication invite an author with an opposing opinion to comment on a controversial article, and then publish the two together. The somewhat similar value “editorial” is reserved for commentary written by an editor or other publication staff.)
Book Review Review or analysis of one or more printed or online books (The similar value “product-review” is used for product analyses.)
Books Received Notification that items, e.g., books or other works, have been received by a publication for review or other consideration
Brief Report A short and/or rapid announcement of research results
Calendar A list of events
Case Report Case study, case report, or other description of a case
Collection Wrapper article for a series of sub-articles or responses; this value’s usage is restricted to articles whose intellectual content appears primarily in sub-article or response.
Discussion Invited discussion related to a specific article or issue
Dissertation Thesis or dissertation written as part of the completion of a degree of study
Editorial Opinion piece, policy statement, or general commentary, typically written by staff of the publication (The similar value “article-commentary” is reserved for a commentary on a specific article or articles, which is written by an author with a contrasting position, not an editor or other publication staff.)
In Brief Summary or teaser of items in the current issue
Introduction An introduction to a publication, or to a series of articles within a publication, etc., typically for a special section or issue
Letter Letter to a publication, typically commenting upon a published work
Meeting Report Report of a conference, symposium, or meeting
News News item, normally current but atypically historical
Obituary Announcement of a death, or the appreciation for a colleague who has recently died
Oration Reprint of a speech or oral presentation
Partial Retraction Retraction or disavowal of part(s) of previously published material
Product Review Description, analysis, or review of a product or service, for example, a software package (The similar value “book-review” is used for analyses of books.)
Rapid Communication Fast-breaking research update or other news item
Reply Reply to a letter or commentary, typically by the original author commenting upon the comments
Reprint Reprint of a previously published article
Research Article Article reporting on primary research (The related value “review-article” describes a literature review, research summary, or state-of-the-art article.) Clinical trials is categorised in this group.
Retraction Retraction or disavowal of previously published material
Review Article Review or state-of-the-art summary article (The related value “research-article” describes original research.) Systematic review or Meta analysis is categorised in this type.
Translation Translation of an article originally produced in a different language
Methods Article Study protocol articles can be for proposed or ongoing prospective clinical research, and should provide a detailed account of the hypothesis, rationale and methodology of the study.
Corrections A modification or correction of previously published material; this is sometimes called “errata”.