NEJM Impact Factor (New England J Medicine)

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 17 Aug 2026

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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.

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.

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.

Worked example of the formula (illustrative only)

If a journal published 1,000 citable items across its two preceding years, and those items collectively received 80,000 citations in the JCR data year, the resulting JIF would be 80,000 / 1,000 = 80 — the same mechanical calculation Clarivate applies to every JCR-indexed journal, shown here only to illustrate the formula, not as a restatement of NEJM’s confirmed current figure.

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

Journal Impact Factor (JIF) — the general metric this page illustrates.
Journal Citation Reports (JCR) — the Clarivate publication a JIF is drawn from.
CiteScore — Elsevier/Scopus’s separately computed journal-level metric, using a different citation window and eligibility criteria than JCR.
DORA — the reform commitment behind the over-reliance caveat above.
How to look up a journal’s Impact Factor — practical guide to finding current, release-dated figures directly from a publisher or Clarivate.
Impact Factor vs. h-index — how journal-level and author-level metrics differ.

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.

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