Writing & StyleStyle guide

Trial Registration Number in Abstract

For a registered clinical trial, place the trial registration number where the target journal requires it; ICMJE recommends the end of the abstract. This is a manuscript-placement guide, not a substitute for the separate trial-registration process or protocol reporting. Follow the journal’s exact location and formatting rules.

Quick answer

For a registered clinical trial, place the trial registration number where the target journal requires it; ICMJE recommends the end of the abstract.

Key details

Core IssueICMJE recommends publishing a clinical-trial registration number at the end of the abstract and also identifying the number when a trial acronym is first used when applicable.
Registerscholarly, professional, or research/report writing

Important caveats

Scope Boundary

This is a manuscript-placement guide, not a substitute for the separate trial-registration process or protocol reporting. Follow the journal’s exact location and formatting rules.

Further guidance

Content

State the registry name when useful and give the exact registration number; verify it against the public record and keep the identifier consistent across abstract, manuscript, submission system, and metadata.

Purpose

Connect the manuscript to its prospective public trial record so readers and indexers can verify the registration.

Sources and evidence

Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.

  1. Preparing a Manuscript for Submission to a Medical Journal — ICMJE (opens in a new tab)International Committee of Medical Journal Editors (ICMJE) · ICMJE manuscript-submission guidance on reporting sources of support/funding that facilitated the work

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