Choose Between Online and Print Publication Dates

Specify the date rule before deciding eligibility

A paper can have an online publication date and a later issue date. Write the protocol's cutoff rule in terms of an event, such as first online publication or assignment to an issue. Record the dates exactly as supplied, keeping date type and precision. JATS supports publication-date metadata that can distinguish these events.

Compare the structured record with the journal landing page when a date determines inclusion. Preserve year-only or month-only values at their original precision. If an incomplete date straddles a cutoff, classify the decision as unresolved until another source or a prespecified handling rule resolves it. An invented day can turn an uncertain record into a falsely certain decision.

Evaluate a hypothetical year-end boundary

A review considers 40 papers near a December cutoff. Thirty-five appear online and in print before the cutoff. Three appear online in December and in print the next January. Two first appear after the cutoff. With an online-first rule, 38 meet the date criterion. With a print-issue rule, 35 do. The difference of three arises entirely from the publication event chosen.

Include the event definition in the methods section and save the source for every borderline record. When reconciling exports, compare both dates before labeling two records as separate publications merely because their citation years differ.

JATS publication date reference

Related worksheet: Eligibility boundary-case worksheet.

Source checked on 5 November 2026.