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Directive Publications

Types of Articles We Publish

The nine article types our journals publish — with the definition, typical structure, and peer-review model for each.

Directive Publications' family of around 96 open-access journals welcomes a range of scholarly article types across medicine, the life sciences, and public health. Whatever its type, every accepted article is published open access under a Creative Commons Attribution (CC BY 4.0) licence — authors retain copyright — receives a Crossref-registered DOI (prefix 10.52338), and is handled in line with COPE Core Practices and the ICMJE Recommendations. The specific types a journal accepts can vary, so please also check the individual journal's page before you submit.

How to use this page

Each article type below is described using the same three-part pattern so the page reads as one consistent system: (a) a short definition, (b) its typical structure, and (c) the type of review it receives. Our review model is double-blind: where an article receives external peer review, author and reviewer identities are mutually concealed (see Peer Review). The table below summarises the nine types at a glance; fuller descriptions follow.

Article typeReview receivedApplicable reporting guideline
Original ResearchFull external double-blind peer reviewCONSORT (RCTs), STROBE (observational), STARD (diagnostic)
Review ArticleFull external double-blind peer review
Systematic Review & Meta-analysisFull external double-blind peer reviewPRISMA (checklist + flow diagram)
Case ReportExternal double-blind peer reviewCARE
Case SeriesExternal double-blind peer reviewSTROBE (where relevant)
Short Communication / Brief ReportFull external double-blind peer reviewPer study design (EQUATOR)
EditorialEditorial review
Commentary / PerspectiveEditorial review (external input at editor's discretion)
Letter to the EditorEditorial review

Original Research

Definition. A complete report of an original primary study presenting new data and findings.

Typical structure. IMRaD — title, abstract, keywords, Introduction, Methods, Results, Discussion, and Conclusion, followed by references. Authors should follow the applicable EQUATOR Network reporting guideline for their design — for example CONSORT for randomised trials or STROBE for observational studies.

Review. Full external double-blind peer review by qualified experts. Length is guided at roughly 4,500–5,000 words; see the Author Guidelines for the definitive limits.

Review Article

Definition. A narrative, expert critical synthesis of a topic — distinct from a systematic review in that its search and selection are not exhaustively pre-specified.

Typical structure. A structured argument organised into thematic sections, supported by a comprehensive, current reference list.

Review. Full external double-blind peer review. Length is guided at roughly 4,000–5,000 words; see the Author Guidelines.

Systematic Review & Meta-analysis

Definition. A study that answers a pre-specified question using explicit, reproducible methods for searching, selecting, and appraising the evidence. A meta-analysis adds a quantitative synthesis of results where the data allow.

Typical structure. A completed PRISMA checklist and flow diagram are required, together with a Methods section describing the full search strategy and eligibility criteria. We encourage protocol registration (for example in PROSPERO), with the registration number stated in the abstract.

Review. Full external double-blind peer review. Because length depends on scope and the number of included studies, we describe it qualitatively — please contact the editorial office or check the target journal's page rather than assuming a fixed word count.

Case Report

Definition. A single, instructive clinical case placed in the context of the existing literature.

Typical structure. Introduction, Case presentation, Discussion, and Conclusion, following the CARE guideline. Documented patient informed consent for publication is required, including consent for any identifiable images.

Review. External double-blind peer review. Length is guided at roughly 1,200–1,600 words; see the Author Guidelines.

Case Series

Definition. A small, consecutive group of related cases reported together, without a control group.

Typical structure. An aggregated presentation of the cases followed by discussion, applying observational-reporting principles (STROBE where relevant). Patient informed consent is required, as for case reports.

Review. External double-blind peer review. Length varies with the number of cases; please refer to the editorial office or the journal's page.

Short Communication / Brief Report

Definition. A concise but complete report of a single, focused finding that merits prompt dissemination.

Typical structure. A compressed IMRaD format with a limited number of figures and tables, following the reporting guideline for the underlying study design.

Review. Full external double-blind peer review — a shorter format held to the same standard of rigour. Length is guided at roughly 1,200–1,300 words; see the Author Guidelines.

Editorial

Definition. A short, authoritative piece — usually invited — that frames a topic, a themed issue, or a scholarly debate.

Typical structure. Brief and argument-led, with light referencing.

Review. Editorial review by the editors or editorial board — not full external double-blind peer review. We state this distinction plainly so readers can interpret each article's status accurately.

Commentary / Perspective

Definition. A scholarly opinion, interpretation, or forward-looking viewpoint on an issue or on a previously published work.

Typical structure. A focused argument with supporting references.

Review. Editorial review, and it may be sent for external input at the editor's discretion.

Letter to the Editor

Definition. Brief correspondence — often a response to a recently published article, or a short original observation.

Typical structure. Very short and tightly focused, with few references.

Review. Editorial review. Where a letter responds to a published article, the authors of the original work may be invited to reply; patient informed consent applies if any identifiable clinical detail is included.

Which review does each type receive?

To summarise the mapping precisely, our journals apply three levels of review:

Reporting standards & manuscript preparation

Authors should follow the EQUATOR Network reporting guideline that matches their study design — CONSORT for randomised trials, PRISMA for systematic reviews and meta-analyses, STROBE for observational studies, CARE for case reports, and STARD for diagnostic-accuracy studies. For definitive word limits, abstract and keyword requirements, title length, reference style, and formatting, please consult the Author Guidelines. We summarise the essentials here and deliberately do not restate the full limits table — the Author Guidelines remain the single source of truth (for example: title up to 28 words; structured abstract of 200–250 words).

Ethics, consent & integrity

Certain requirements apply across every article type. Authors must disclose competing interests and funding, and meet the ICMJE criteria for authorship. Case reports, case series, and any identifiable images require documented patient informed consent for publication. Studies should include a data-availability statement where relevant, and all submissions undergo similarity screening. These expectations are set out in full in our Publication Ethics policy and the Author Guidelines. We also encourage every author and reviewer to register an ORCID iD.

Not sure which type fits?

If you are unsure which category best suits your manuscript, first check the target journal's page — the types offered can vary by journal — and then, if you still have questions, contact us. Our editorial team is glad to advise before submission. Start your submission at Submit a Manuscript, review the Author Guidelines, reach us through Contact, or email [email protected].

Frequently Asked Questions

Which article types receive external peer review, and which receive editorial review?
Original Research, Review Articles, Systematic Reviews & Meta-analyses, and Short Communications receive full external double-blind peer review by at least two qualified reviewers. Case Reports and Case Series receive external double-blind peer review at a depth appropriate to their scope. Editorials, Letters to the Editor, and (typically) Commentaries/Perspectives receive editorial review by the editors or editorial board, and commentaries may be sent for external input at the editor's discretion. See our Peer Review policy for full details.
Do I need to follow a reporting guideline such as PRISMA, CONSORT, CARE, or STROBE for my article type?
Yes, where one applies. Authors should follow the relevant EQUATOR Network guideline for their study design: CONSORT for randomised trials, PRISMA for systematic reviews and meta-analyses, STROBE for observational studies, CARE for case reports, and STARD for diagnostic-accuracy studies. Systematic reviews and meta-analyses must include a completed PRISMA checklist and flow diagram.
What are the word limits for each article type?
Indicative limits include roughly 4,500–5,000 words for Original Research, 4,000–5,000 for Review Articles, 1,200–1,600 for Case Reports, and 1,200–1,300 for Short Communications, with a title up to 28 words and a structured abstract of 200–250 words. For Systematic Reviews & Meta-analyses, Case Series, Editorials, Commentaries, and Letters, length depends on scope — please refer to the Author Guidelines or the editorial office. The Author Guidelines are the definitive source for all limits.
Do case reports and case series require patient consent to publish?
Yes. Both case reports and case series require documented patient informed consent for publication, including consent for any identifiable images. Letters that include identifiable clinical detail are subject to the same requirement.
Are editorials, commentaries, and letters to the editor invitation-only, or can I submit them unsolicited?
Editorials are usually invited, but commentaries, perspectives, and letters to the editor may be submitted unsolicited. Because practice varies by journal, we recommend checking the target journal's page or contacting the editorial office at [email protected] before you submit.
Which of these article types does a specific journal accept?
The article types accepted can vary from journal to journal. Please check the individual journal's page for the types it currently welcomes, and consult the Author Guidelines for preparation requirements. If you are still unsure, contact our editorial team at [email protected] for advice before submission.