What Is an ISSN?
An ISSN (International Standard Serial Number) is an eight-digit number that identifies a serial publication, such as a journal or magazine, regardless of the individual articles it contains. Print and online versions of the same journal usually have different ISSNs.
Example
Illustrative format only: 1234-5678. When you check whether a journal is indexed in PubMed, searching by ISSN helps avoid confusion between journals with similar names.
Common misunderstanding
Having an ISSN does not mean that a journal is peer reviewed, reputable or indexed in any database. Anyone running a periodical can obtain one, so check quality using other signals.
Where this matters
ISSNs help catalogues, libraries and databases identify the right journal. They differ from DOIs, which identify individual articles, and from PMIDs, which identify PubMed records.
References and further reading
- ISSN International Centre. What is an ISSN? Link
This page is general educational information about research methods. It is not medical, legal or regulatory advice; follow your institution's ethics board and your target journal's instructions.