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New England Journal of Medicine’s Journal Impact Factor (JIF)

The New England Journal of Medicine's Journal Impact Factor (JIF) is the Clarivate-computed, journal-level citation ratio the Massachusetts Medical Society's flagship clinical-medicine journal receives each year in the Journal Citation Reports (JCR) -- citations in the JCR data year to the journal's citable items from the two preceding years, divided by that item count. NEJM (ISSN 0028-4793 print, 1533-4406 online) has published continuously since 1812, making it one of the oldest continuously published medical journals in the world, and is indexed in Clarivate's Science Citation Index Expanded, which makes it JIF-eligible. Third-party JCR-tracking aggregators report NEJM's 2-year JIF in the high-70s to mid-80s range for recent releases -- figures cited include roughly 78.5 and roughly 84.5 for figures described as the '2025 impact factor,' attributed inconsistently to the 2025 versus 2026 JCR release across different aggregator pages -- with a reported 5-year JIF near 84.9. These aggregator figures do not agree with one another even when describing what appears to be the same release, and NEJM's own journal-information page was not independently reachable to confirm one authoritative figure at the time of writing (returned an access-restricted response during verification). Treat any single number you see cited as time-stamped to a specific JCR release -- Clarivate updates JCR every June -- and check jcr.clarivate.com or nejm.org directly for the current, release-dated figure before citing it in a formal context such as a CV, grant application, or tenure file. Per DORA (San Francisco Declaration on Research Assessment) and CoARA guidance, this journal-level figure should not be used as a proxy for the quality of any individual article NEJM has published, nor of the researchers who authored it.

ByCASRAI Editorial Board
· Last updated 4 Sept 2026
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Examples

Worked examples

  • Is an instance

    A researcher checking NEJM's current JCR entry against JAMA's or The Lancet's separately computed JIF before comparing the relative citation impact of the general-medicine journals they are considering for a manuscript, while treating the comparison as journal-level only.

  • Is an instance

    A grants office noting in an internal metrics reference that NEJM is Science Citation Index Expanded-indexed and therefore receives an annual JIF from Clarivate, distinct from journal ranking tools like Scopus's CiteScore, which uses a different citation window and denominator.

Counter-examples

Looks similar, but isn't

  • Not an instance

    Citing a single NEJM impact-factor figure pulled from an aggregator site as if it were the authoritative, current number without noting the JCR release year it reflects -- aggregator figures for NEJM diverge from one another and change with each annual JCR update.

  • Not an instance

    Using NEJM's high JIF to argue that a specific article published in NEJM is more rigorous or more important than a comparable article published in a lower-JIF journal -- the JIF is a journal-level average, not an article-level or author-level quality measure, per DORA.

Editorial commentary

The New England Journal of Medicine’s Journal Impact Factor (JIF) is the Clarivate-computed, journal-level citation ratio the Massachusetts Medical Society’s flagship clinical-medicine journal receives each year in the Journal Citation Reports (JCR) — citations in the JCR data year to the journal’s citable items from the two preceding years, divided by that item count. NEJM (ISSN 0028-4793 print, 1533-4406 online) has published continuously since 1812, making it one of the oldest continuously published medical journals in the world, and is indexed in Clarivate’s Science Citation Index Expanded, which makes it JIF-eligible. Third-party JCR-tracking aggregators report NEJM’s 2-year JIF in the high-70s to mid-80s range for recent releases — figures cited include roughly 78.5 and roughly 84.5 for figures described as the ‘2025 impact factor,’ attributed inconsistently to the 2025 versus 2026 JCR release across different aggregator pages — with a reported 5-year JIF near 84.9. These aggregator figures do not agree with one another even when describing what appears to be the same release, and NEJM’s own journal-information page was not independently reachable to confirm one authoritative figure at the time of writing (returned an access-restricted response during verification). Treat any single number you see cited as time-stamped to a specific JCR release — Clarivate updates JCR every June — and check jcr.clarivate.com or nejm.org directly for the current, release-dated figure before citing it in a formal context such as a CV, grant application, or tenure file. Per DORA (San Francisco Declaration on Research Assessment) and CoARA guidance, this journal-level figure should not be used as a proxy for the quality of any individual article NEJM has published, nor of the researchers who authored it.

What the JIF formula actually measures

The Journal Impact Factor is a ratio Clarivate computes the same way for every Web of Science Core Collection-indexed journal: citations received in a given JCR data year to a journal’s citable items (articles and reviews) published in the two preceding years, divided by the number of those citable items. It is a journal-level average, not a per-article or per-author score.

Current status: no single confirmed figure stated as fact

The current JCR cycle is the 2025 data year, released June 2026. During verification of this page, third-party JCR-tracking aggregators reported NEJM’s 2-year JIF inconsistently — figures around 78.5 and around 84.5 both appear attributed to “the 2025 impact factor” across different aggregator pages, with a reported 5-year JIF near 84.9 — and these aggregator figures do not agree with each other even when apparently describing the same release. NEJM’s own site did not return a page independently confirming one authoritative, release-dated figure at the time of this check. Because of that discrepancy, no single number is stated as NEJM’s current confirmed JIF on this page. Readers who need the authoritative, release-dated figure should check nejm.org directly, or consult Clarivate’s Journal Citation Reports (jcr.clarivate.com) through an institutional subscription — Clarivate republishes the JCR every June, so re-check after each release rather than reusing a cached number.

Why NEJM is JIF-eligible at all

NEJM (ISSN 0028-4793 print, 1533-4406 online) has published continuously since 1812, making it one of the oldest continuously published medical journals in the world. It is indexed in Clarivate’s Science Citation Index Expanded (SCIE), which is what makes it eligible to receive an annual JIF in the first place — the same underlying indexing requirement that applies to any journal receiving a JIF.

Why the number alone is a poor stand-in for quality

Per DORA (San Francisco Declaration on Research Assessment) and CoARA’s responsible-assessment guidance, NEJM’s journal-level JIF should not be used as a proxy for the quality or rigor of any individual article NEJM has published, nor of the researchers who authored it. A journal’s JIF is heavily shaped by a small number of highly cited papers (NEJM regularly publishes practice-changing clinical trials and reviews that draw outsized citation volume) and by field-level citation norms in clinical medicine, not by the quality of any one specific paper.

Worked examples

  • A researcher checking NEJM’s current JCR entry against JAMA’s or The Lancet’s separately computed JIF before comparing the relative citation impact of the general-medicine journals they are considering for a manuscript, while treating the comparison as journal-level only.
  • A grants office noting in an internal metrics reference that NEJM is Science Citation Index Expanded-indexed and therefore receives an annual JIF from Clarivate, distinct from journal ranking tools like Scopus’s CiteScore, which uses a different citation window and denominator.

Counter-examples

  • Citing a single NEJM impact-factor figure pulled from an aggregator site as if it were the authoritative, current number without noting the JCR release year it reflects — aggregator figures for NEJM diverge from one another and change with each annual JCR update.
  • Using NEJM’s high JIF to argue that a specific article published in NEJM is more rigorous or more important than a comparable article published in a lower-JIF journal — the JIF is a journal-level average, not an article-level or author-level quality measure, per DORA.

Related terms and guides

The New England Journal of Medicine’s Impact Factor in 2026: what the named sources actually say

The New England Journal of Medicine’s Journal Impact Factor is 84.5, for the 2025 JCR data year — the release Clarivate issued in June 2026. The source is NEJM’s own About page (nejm.org/about-nejm/about-nejm), which cites Journal Citation Reports on-page. It appears there verbatim as “With a 2025 Journal Impact Factor of 84.5, NEJM is a top-ranked, global, multi-specialty journal in the Medicine, General & Internal category”, retrieved 23 August 2026. That is the publisher restating Clarivate’s number for its own title — not a third-party JCR-tracking aggregator and not a Wikipedia infobox, either of which can lag behind or drift from the release Clarivate actually issued.

Sources disagree, so here are both. An earlier version of this page reported that third-party trackers disagreed with each other, showing figures around 78.5 and around 84.5 both attributed to the 2025 Impact Factor, plus a 5-year figure near 84.9. That disagreement is now resolved: the publisher itself states 84.5 for the 2025 data year. Note the NLM Catalog also carries a separate record for the NEJM “Overseas ed.”, which is not currently indexed for MEDLINE; that record describes a different edition and should not be mistaken for the main journal.

Clarivate republishes the JCR every June, so this figure is current only for the 2025 data year. Re-check it at the publisher’s page or in JCR itself before putting it in a CV, tenure file, grant application or funder report — and say which data year you mean when you cite it.

What CASRAI could verify at source

  • ISSN: 0028-4793 (print), 1533-4406 (online) — Crossref journal record, checked 23 August 2026.
  • Publisher: Massachusetts Medical Society — Crossref journal record, checked 23 August 2026.
  • PubMed / MEDLINE: Currently indexed for MEDLINE; MEDLINE coverage v273n9, Aug. 26 1965- — NLM Catalog record, checked 23 August 2026.
  • DOAJ: Not listed in DOAJ (subscription journal) — DOAJ API, checked 23 August 2026.
  • Journal Impact Factor: 84.5 for the 2025 JCR data year — NEJM’s own About page (nejm.org/about-nejm/about-nejm), which cites Journal Citation Reports on-page, retrieved 23 August 2026.

Frequently Asked Questions

What is NEJM’s current impact factor?

CASRAI could not confirm one authoritative, current figure directly from nejm.org during verification, and third-party aggregators disagree with each other on the exact number for the current 2025-data-year/June-2026 release (reported figures span roughly the high 70s to mid 80s). Check jcr.clarivate.com or nejm.org directly for the release-dated figure before citing a specific number formally.

How is NEJM’s Impact Factor calculated?

Like every JCR-indexed title, it is a ratio: citations received in a given year to the articles and reviews NEJM published in the two preceding years, divided by the number of those citable items. Clarivate applies this same formula to every Web of Science-indexed journal.

Why do different websites show different NEJM impact factor numbers?

Aggregator sites frequently do not clearly label which JCR release year a figure reflects, mirror stale cached values, or otherwise diverge from Clarivate’s own release. Treat any number you find on a third-party site as unverified until you confirm it against jcr.clarivate.com or NEJM’s own official communications for a stated release year.

Does a high impact factor mean every NEJM article is high quality?

No. Per DORA and CoARA guidance, the JIF is a journal-level average shaped disproportionately by a small number of highly cited papers — it should not be used to judge the merit of any individual article or its authors.

What is NEJM’s ISSN?

0028-4793 (print) and 1533-4406 (online).

Last verified 2026-08-16. CASRAI attempted direct verification against nejm.org’s own information pages this session; no page independently confirming a single current, release-dated JIF figure was located, so no specific number is stated as current fact on this page. Clarivate republishes the Journal Citation Reports every June — re-check this page after the next release.

Machine-readable encodings

Use in your systems

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