What Do Journal Metrics Really Mean?

Understanding Impact Factor, h-index, Altmetrics, and CAS Journal Ranking

Journal metrics can be helpful, but they can also be misleading when used without context.

For researchers, metrics often influence where to submit a manuscript. For institutions, they may shape evaluation, promotion, and funding decisions. For journals and publishers, they affect visibility, reputation, and positioning in a crowded scholarly ecosystem.

But no single metric can tell the full story of research quality, journal credibility, or publication impact. Metrics are best understood as signals, useful indicators that need interpretation, not absolute measures of value.

This article explains four commonly discussed metrics, Impact Factor, h-index, Altmetrics, and CAS Journal Ranking, and how researchers can use them more thoughtfully when making publishing decisions.

Why Journal Metrics Matter

Journal metrics are mathematical indicators used to measure and compare the citation performance of journals. They can help researchers identify journals that are visible in a field, understand how journals compare within a discipline, and make more informed submission decisions. VCU Libraries describes journal metrics as tools for comparing citation performance across journals, while Johns Hopkins notes that journal metrics can support decisions about where to submit manuscripts.  [1, 2]

However, metrics should not be confused with quality itself. A journal may have strong metrics but still not be the best fit for a particular manuscript. Likewise, an article published in a lower-ranked or newer journal may still have significant scientific, clinical, educational, or societal value.

The key question is not simply: “Which journal has the highest number?”It is: “Which journal gives this research the best chance to reach the right audience?”

Impact Factor: The Familiar but Imperfect Standard

The Journal Impact Factor is one of the most widely recognized journal-level metrics. It reflects the average number of citations received each year by articles published in a journal during a recent two-year period. The Peeref article correctly notes that Impact Factor was originally developed to help librarians evaluate journals, but it has since become widely used as a proxy for journal prestige.  [2, 4]

Impact Factor can be useful because it gives researchers a general sense of a journal’s visibility within its field. Many authors still use it when preparing target journal lists, and many institutions still consider it in evaluation contexts.

But Impact Factor has important limitations:

• It measures journals, not individual articles.

• It reflects an average, which can be skewed by a small number of highly cited papers.

• It varies dramatically by discipline.

• It does not guarantee that a specific article will be widely read or cited.

A useful example is CA: A Cancer Journal for Clinicians, which has consistently held one of the highest Impact Factors in academic publishing. Its 2023 Impact Factor, released in 2024, exceeded 500 — an extraordinary figure driven largely by its highly cited annual cancer statistics reports. By comparison, Cancer has an Impact Factor closer to 5–6. However, this does not mean that CA: A Cancer Journal for Clinicians is “100 times better” than Cancer. Rather, it illustrates how a small number of exceptionally cited article types can dramatically influence a journal’s average citation metrics, reinforcing why Impact Factor should be interpreted carefully and within context.

In practice, Impact Factor should be used as one piece of evidence, not as the deciding factor. A strong journal fit also depends on scope, audience, editorial standards, peer review process, indexing, article type, acceptance likelihood, publication speed, and regional visibility.

Accdon Insight: Impact Factor can help researchers understand journal positioning, but it should never replace strategic journal selection.

h-index: Measuring Researcher Output and Citation Influence

The h-index is usually used to evaluate an individual researcher rather than a journal. It combines productivity and citation impact into one number. A researcher has an h-index of 10, for example, if they have 10 papers that have each been cited at least 10 times. Einstein Library describes the h-index as a measure of a scientist’s impact that accounts for both number of papers and citation performance.  [3]

The h-index is popular because it is relatively easy to understand and appears on platforms such as Google Scholar and Scopus.

It can be useful for:

• summarizing a researcher’s publication record;

• comparing researchers in the same field;

• showing sustained citation influence over time.

But the h-index also has limitations:

• It favors senior researchers with longer careers.

• It varies by discipline.

• It does not account for author contribution or author order.

• It can differ depending on the database used.

• It does not capture emerging influence or non-citation impact.

For early-career researchers, interdisciplinary scholars, and researchers working in lower-citation fields, the h-index can understate contribution.

Accdon Insight: The h-index is best viewed as a career-level citation indicator, not a complete measure of research quality, originality, or future potential.

Altmetrics: Measuring Attention Beyond Citations

Traditional metrics focus heavily on citations. Altmetrics broadens the picture by tracking online attention and engagement around research outputs.

These may include:

• news coverage;

• social media mentions;

• policy document references;

• blog posts;

• online reference managers;

• public discussion.

VCU Libraries notes that altmetrics can help capture engagement with research beyond journal citations and may apply to many types of research outputs.  [1]

Altmetrics are especially useful because they often appear much sooner than citations. A paper may receive public attention, policy relevance, or media coverage long before it accumulates formal academic citations.

This makes altmetrics valuable for understanding:

• early visibility;

• public engagement;

• policy or clinical relevance;

• broader societal interest;

• dissemination beyond academia.

However, altmetrics should be interpreted carefully. Online attention is not the same as scholarly quality. A paper may receive attention because it is controversial, surprising, timely, or widely shared, not necessarily because it is methodologically strong.

Accdon Insight: Altmetrics help show how research travels beyond academic publishing, but they should be paired with citation-based and qualitative indicators.

CAS Journal Ranking: A China-Focused Evaluation Framework

The Chinese Academy of Sciences (CAS) Journal Ranking System has historically been one of the most influential journal evaluation frameworks in China’s scholarly ecosystem. For many researchers and institutions, CAS tiers significantly influenced journal perception, submission behavior, and institutional evaluation.

Unlike a simple Impact Factor ranking, the CAS system used a tiered model and field-normalized approaches. The Peeref article notes that the system was developed partly to reduce overreliance on Impact Factor and incorporated indicators such as the Field Normalized Citation Success Index (FNCSI), which evaluates how often papers outperform comparable work within similar disciplines. [4]

One reason the CAS system became influential was its attempt to account for disciplinary differences. Citation behavior varies widely across fields, meaning raw citation averages alone can create misleading comparisons between disciplines.

However, the CAS ranking system was officially discontinued in 2026, and successor initiatives are currently working to develop comparable frameworks, with ongoing discussion and refinement within the scholarly publishing community. [5]

This development highlights an important reality: journal evaluation systems themselves evolve over time and should not be treated as fixed or universally authoritative measures of quality.

For researchers and publishers working in China-facing markets, understanding the historical importance of CAS rankings still matters. But it also reinforces the broader lesson that metrics and ranking systems require careful interpretation, especially when methodologies, governance, and community trust are changing.

Accdon Insight: Journal rankings can strongly influence researcher behavior and publishing strategy, particularly in large research markets such as China. However, no ranking system should be interpreted in isolation or treated as a permanent measure of journal quality.

Comparing the Metrics

Metric	What It Measures	Best Used For	Main Limitation
Impact Factor	Average journal citation performance	Understanding journal visibility	Not article-specific
h-index	Researcher productivity and citations	Author-level citation influence	Biased by career length and field
Altmetrics	Online and public attention	Early visibility and societal engagement	Attention does not equal quality
CAS Ranking	Field-adjusted journal standing, especially in China	China-facing journal evaluation	Regional relevance and complexity

The Bigger Issue: Metrics Without Strategy

The problem is not that researchers use metrics. The problem is that metrics are often used too narrowly.

A researcher may choose a journal only because it has a high Impact Factor, even if the journal is not the best audience fit. A publisher may promote a journal’s ranking without explaining what that ranking means to authors. An institution may rely on citation indicators without considering discipline, career stage, article type, or research purpose.

Better publishing decisions come from asking more precise questions:

• Is this journal visible to the right research community?

• Is it indexed where the author’s institution expects?

• Does it have a credible editorial process?

• Does it reach the intended geographic or disciplinary audience?

• Is the journal’s reputation strong in the author’s home market?

• Are the metrics appropriate for this field?

• Does the article have potential for broader engagement beyond citations?

This is where metrics become useful, not as isolated numbers, but as part of a broader publishing strategy.

How Researchers Should Use Metrics

Researchers should use metrics to inform, not dictate, journal selection.

A practical approach includes:

1. Start with journal scope and audience.

   
   

   The best journal is not always the highest-ranked journal. It is the journal most likely to reach the right readers.

2. Check multiple indicators.

   
   

   Impact Factor, CiteScore, quartile rankings, h-index, acceptance rate, indexing, peer review timelines, and article-level engagement can all provide useful context.

3. Interpret metrics by field.

   
   

   Citation behavior differs across disciplines, so cross-field comparisons can be misleading.

4. Consider regional relevance.

   
   

   Evaluation systems and journal reputations can vary significantly by region. In China, CAS rankings historically carried significant weight, though the system is now in transition and should be interpreted with caution. In other regions, JCR, Scopus, indexing status, society reputation, or institutional expectations may be more influential.

5. Look beyond prestige.

   
   

   Visibility, credibility, editorial quality, speed, audience fit, and post-publication discoverability all matter.

The Accdon Perspective

Journal metrics are not simply numbers. They shape behavior.

They influence where researchers submit, how journals compete, how institutions evaluate output, and how publishers position their portfolios. But when metrics are treated as shortcuts, they can distort good decision-making.

At Accdon, we believe metrics should support a more informed, transparent, and strategic publishing process. Researchers need help understanding what metrics mean, what they do not mean, and how to apply them in the context of their own goals.

For publishers and societies, the opportunity is equally important. Clearer metric education can help authors make better submission decisions, build trust, and strengthen journal positioning ,  especially in global and China-facing markets where evaluation systems differ.

The strongest publishing decisions come from combining data, context, editorial judgment, and audience strategy.

Metrics matter.But interpretation matters more.

References

[1] Virginia Commonwealth University Libraries. “Understand the Uses and Limitations of Journal Metrics.”https://guides.library.vcu.edu/identify-journals/metrics

[2] Johns Hopkins University Libraries. “Journal Metrics – Scholarly Metrics.”https://guides.library.jhu.edu/metrics/journal-metrics

[3] Albert Einstein College of Medicine Library. “Publication Metrics: Journal-level Metrics.”https://library.einsteinmed.edu/c.php?g=123507&p=808388

[4] Peeref. “What Do Journal Metrics Really Mean? Understanding IF, h-index, Altmetrics, and CAS Journal Ranking.”https://www.peeref.com/e-collections/what-do-journal-metrics-really-mean-understanding-if-h-index-altmetrics-and-cas-journal-ranking

[5] Nature. “China discontinues prominent journal ranking list.”https://www.nature.com/articles/d41586-026-01216-1