Instructions for Authors

02 · Limits

Length and count limits

These are the publisher’s manuscript limits and they apply to every article type.

The Methods, Results and Conclusion sections carry no fixed limit: Methods should hold enough detail for a qualified reader to repeat the work, Results only the findings the study turns on, and the Conclusion a precise summary beginning with the principal finding.

Where a manuscript needs more room than a limit allows — a large systematic review, a complex multi-site protocol — write to the editorial office before submitting.

03 · Structure

How to arrange the manuscript

Submit the manuscript as a single editable file, with tables and figures at the end, each on its own page.

• 01Title pageTitle, running title, every author’s full name, affiliations and discipline, and full contact details for the corresponding author. The first author is listed first. Keep this in a separate file where double-blind review is requested.
• 02Structured abstractObjectives, methods, results and conclusions, within the word limit above and including any citations.
• 03KeywordsFive to twelve, comma separated, chosen to describe what the study actually measured.
• 04IntroductionThe objectives, the background they rest on, and the hypotheses tested.
• 05MethodsEnough detail for a qualified reader to replicate the work. Cite previously published procedures rather than restating them. State the sex or gender of participants and name the suppliers of materials and equipment.
• 06ResultsThe findings essential to the study, with the statistical tests used to reach them.
• 07DiscussionPrincipal findings, the validity of the observations, comparison with published work, significance and limitations.
• 08ConclusionA precise summary of the results and, where relevant, what they open up.
• 09AcknowledgmentsFunding sources, and intellectual or technical help that falls short of authorship. Tell the people named before publication. Promotional statements belong elsewhere.
• 10DeclarationsCompeting interests, funding, data availability, ethics approval, consent and declared AI use, as set out in section 07.

04 · Sleep methods

Reporting a sleep or circadian study

What a reader needs in order to interpret a sleep study depends on how it was done. Report what applies to the design in hand.

• The recording or measurement used, named precisely — the device, montage, sampling rate, channels or questionnaire and its version.
• The scoring rules applied, including the manual or criteria used and the version, and whether scoring was manual, automatic or both.
• Scorer reliability where more than one scorer contributed, and how disagreements were resolved.
• The setting and schedule: laboratory or home, number of nights or days, any adaptation night, and the time of day of any daytime testing.
• Participant sleep context: habitual schedule, shift work, time zone, season and light exposure where these bear on the question.
• Medication, caffeine, alcohol and substance use where they could affect the measurements.
• The definitions behind derived variables — how an event, an arousal, a stage transition or a summary index was defined in this study.
• For model-system and non-human work, the species, strain, age, housing light schedule and the equivalent recording and scoring detail.

Report the guideline that matches the design and supply the completed checklist: CONSORT for randomized trials, STROBE for observational studies, PRISMA for systematic reviews, CARE for case reports, STARD for diagnostic accuracy, ARRIVE for animal research.

05 · Figures and data

Figures, tables, data and code

Figures

High resolution, properly sized, each with a title and legend. Numbers, letters and symbols stay readable at no smaller than 2 mm after reduction. Label axes and give units. Color palettes should remain legible to readers with color vision deficiency, and figure legends should state sample sizes and data sources.

Tables

Editable rather than pasted images, each with a title, clear headings and footnotes where a cell needs explanation.

Placement

Tables and figures go at the end of the manuscript, each on a separate page, and each is referred to in the text.

Supplementary files

Labeled clearly and cited in the text at the point they support.

Data

Every empirical research manuscript must include a data-availability statement. The statement says where the data are, how they may be obtained and on what terms, with the repository and accession or DOI for anything deposited. Where participant confidentiality limits sharing, the statement says so and gives the access route.

Code

Analysis code, scoring rules and processing pipelines are shared or documented in enough detail to repeat the analysis, including software versions and parameters.

06 · References

Citing and referencing

References are cited by number rather than by author and date.

• Number references consecutively in the order they first appear in the text.
• List the first 3 authors, then “et al.” for the remainder.
• Include the DOI wherever one exists.
• Check that every in-text citation appears in the reference list and that every listed reference is cited.
• Authors are responsible for the accuracy of their references.

Examples

• Journal article. Tzischinsky O, Latzer Y, Givon M, et al. Subjective and objective actigraphic sleep monitoring and psychopathology in a clinical sample of patients with night eating syndrome. J Sleep Sleep Disord Res. 2015;1(1):1–14. doi:10.14302/issn.2574-4518.jsdr-14-554
• Book. Author AA. Title of Book. 2nd ed. City: Publisher; Year.
• Book chapter. Author AA, Author BB. Title of chapter. In: Editor CC, ed. Title of Book. City: Publisher; Year:pages.
• Web page. Organization or author. Title of page. Publication or update date. URL. Accessed date.
• Dataset. Author AA. Title of dataset. Repository; Year. doi:...
• Preprint. Author AA, Author BB, Author CC, et al. Title. Preprint server. Year. doi:...
• Trial registration. Registry name. Trial title. Registration number. Registration date. URL.

07 · Declarations

What to declare, and how

Competing interests

Financial and non-financial interests relevant to the work, declared in the cover letter and published with the article.

Funding

Every funder, with the award or grant number and the part the funder played in design, conduct, analysis or reporting.

Ethics approval

The approving committee or review board and the approval reference, with a statement that the work followed the Declaration of Helsinki.

Consent

Consent to take part and to publish. Where a participant could be identified, explicit consent to publish that material is obtained and reported.

Clinical trials

Interventional clinical trials must be registered in an accepted public trial registry at or before the first participant provides consent for enrollment. The registry name, registration number, and registration date must be reported in the manuscript.

AI use

Disclose the use of generative AI in producing the manuscript, naming the tool and what it was used for. Authorship is held by people; the authors remain responsible for everything the submission contains.

Double-blind preparation

For double-blind review, remove author names, affiliations, acknowledgments, funding details, institution names, and other identifying information from the reviewer manuscript. Provide identifying information separately in the title-page file or submission form.

The full requirements behind each declaration are in the editorial policies.

08 · Submitting

Sending the manuscript

Authors must use only one submission route for the same manuscript.

1. Primary route — ManuscriptZoneThe journal’s submission system.oap.manuscriptzone.net
2. Alternative route — Manuscript submission formA simple form that records the manuscript and its files, preset to this journal.openaccesspub.org/manuscript-submission-form
3. Assisted route — Editorial officeAuthors who need assistance may write to the editorial office.[email protected]

Before you send it

• The subject fits the journal’s scope.
• The article type is chosen and the manuscript is within the limits for it.
• The title page carries every author, affiliation and the corresponding author’s contact details.
• Tables and figures are at the end, each on its own page, each cited in the text.
• References are numbered in citation order, with DOIs where available.
• Ethics approval, consent, funding, competing interests, data availability and any AI use are declared.
• The reporting checklist for the study design is completed and attached.
• Where double-blind review is requested, identifying information is held in the title-page file rather than the manuscript.

All submissions undergo initial editorial screening. Manuscripts that meet the journal's scope and minimum requirements proceed to independent peer review. Single-blind by default; double-blind review is available on request.