1. Introduction
Calls for papers frequently describe a journal as "Web of Science indexed". The phrase may be accurate, but on its own it conveys limited information, because Web of Science comprises several indexes, and the differences between them are often precisely what institutional policies depend on.
This article describes the four indexes most often cited in such policies, distinguishes the differences that matter from those that do not, and suggests how researchers might interpret their own institution's wording before committing a manuscript to a particular venue.
2. The four indexes
| Index | Coverage | Selective Core Collection index? |
|---|---|---|
| SCIE | Science Citation Index Expanded: the sciences, broadly defined | Yes |
| SSCI | Social Sciences Citation Index | Yes |
| AHCI | Arts & Humanities Citation Index | Yes |
| ESCI | Emerging Sources Citation Index: multidisciplinary | No; journals meet the quality criteria but not the additional impact criteria |
Most of the practical consequences discussed below follow from the final column.
3. SCIE, SSCI, and AHCI are parallel, not ranked
A common misunderstanding is that these three indexes form a hierarchy. This assumption can lead to poorly informed decisions and is therefore worth addressing first.
SCIE, SSCI, and AHCI are the three selective indexes of the Web of Science Core Collection. The index in which a journal appears reflects its subject matter rather than its standing. A journal is listed in SSCI because it publishes social science research, not because it is judged superior or inferior to a journal in SCIE. There is no formal hierarchy among the three.
Journals are frequently listed in more than one index. An educational psychology journal may appear in both SSCI and SCIE, and a journal on the history of medicine may appear in both AHCI and SCIE. Such dual listing reflects interdisciplinary scope rather than additional quality.
All three indexes apply the same broad editorial criteria, including peer review, ethical publishing practices, bibliographic information in English, timeliness, and citation-based evidence of significance within the field.
4. ESCI as a distinct tier
ESCI was introduced in 2015. It covers journals that meet Clarivate's 24 quality criteria, which concern peer review, publication ethics, and editorial rigour, but that have not met the four additional impact criteria required for inclusion in SCIE, SSCI, or AHCI.
Two practical points follow:
- Impact Factors. Until 2023, ESCI journals did not receive a Journal Impact Factor (JIF). From the 2023 release of the Journal Citation Reports, Clarivate extended the JIF to all journals in the Core Collection, including those in ESCI and AHCI (Clarivate, 2023). Guidance that states ESCI journals have no Impact Factor is therefore out of date. Because Clarivate's practices continue to change, it is advisable to consult the current JCR entry for a specific journal rather than relying on a general rule.
- Institutional policies. Many policies refer specifically to the selective indexes, either by name or by a phrase such as "SCIE/SSCI journals". Where this is the case, ESCI journals may not qualify, and it is in this area that careers are most often affected.
None of this implies that ESCI journals are of low quality. Many are well regarded, including new journals in emerging fields, strong regional journals publishing in English, and specialist journals too small to generate the citation volumes the selective indexes require. Some subsequently move into the selective indexes. Publishing sound work in a reputable ESCI journal is entirely legitimate.
The issue is narrower and largely administrative: ESCI is not equivalent to SSCI or SCIE where an institution's policy specifies those indexes, and difficulties tend to arise when this is discovered after acceptance rather than before submission.
5. Interpreting institutional wording
The most useful step a researcher can take is to locate the relevant document, such as the promotion regulations, probation criteria, or research output policy, and to read its exact wording. Formulations vary considerably, and each can carry a different meaning.
| If the policy refers to… | A likely interpretation |
|---|---|
| "Web of Science indexed" | ESCI probably qualifies. This is among the least restrictive common wordings. |
| "Web of Science Core Collection" | ESCI is technically part of the Core Collection, but some institutions use this phrase to mean the selective indexes only. Clarification is advisable. |
| "SSCI or SCIE" | Only the named indexes qualify. ESCI and AHCI are likely to be excluded. |
| "Journals with an Impact Factor" | Since 2023, this may include ESCI and AHCI journals. The current JCR entry for the specific journal should be checked. |
| "Scopus indexed" or "Q1–Q2" | A separate system: SCImago quartiles based on Scopus, not Web of Science. A journal can be Q1 in Scopus and absent from Web of Science. |
Where a policy is ambiguous, it is prudent to request clarification in writing and to retain the response. Ambiguities resolved only verbally may be interpreted differently at the time of assessment.
6. Scopus and Web of Science are independent
Tools that display information from both databases side by side can imply a relationship that does not exist. Scopus (Elsevier) and Web of Science (Clarivate) are competing products with different coverage and selection criteria. A journal may be:
- Q1 in Scopus and not indexed in Web of Science;
- indexed in SSCI and ranked Q3 in Scopus;
- indexed in both, with positions that do not correspond; or
- indexed in neither and still legitimate, particularly in fields where conferences or monographs are the principal venues.
Neither system validates the other. Where an institution specifies one, the other is unlikely to be accepted as a substitute.
7. What indexing does not indicate
Indexing is a coverage decision made by a commercial database. It is a meaningful signal, but a limited one.
It does not indicate whether a specific article is sound, whether peer review at the journal has been rigorous in recent years, whether the journal's scope suits a particular manuscript, whether the intended readership is present, or how long review is likely to take. These factors largely determine whether a submission is well judged, and indexing status addresses none of them.
The converse also holds: the absence of indexing is not, in itself, evidence of poor quality. Much influential work in computer science appears in refereed conference proceedings that journal indexes do not cover, and much work in the humanities appears in monographs. A new journal founded by respected scholars will, by definition, be unindexed in its early years.
8. A suggested sequence before submission
- Read the institutional policy. Establish which database and which index tier apply.
- Check the journal at the source. Use mjl.clarivate.com for Web of Science indexing and scimagojr.com for Scopus quartiles. Third-party tools rely on periodic snapshots, and indexing can change during the year.
- Check coverage years. A Scopus coverage period that ended recently usually indicates that the journal has been discontinued from the database, in which case new articles are unlikely to be indexed.
- Assess fit. Reviewing recent issues gives a more reliable indication of scope than the aims statement alone. If little resembles the manuscript, indexing status is of secondary importance.
- Then consider quartile and index tier.
If a journal appears in neither Scopus nor Web of Science, this warrants further investigation rather than automatic exclusion. The journal may be new and legitimate, or it may be predatory. The Journal Intelligence tool is intended to assist with this distinction, subject to the caveats set out in its disclaimer.
9. Conclusion
This article has described how to navigate a measurement system rather than how to conduct good research. The two are related, but the relationship is arguably looser than the institutional machinery implies.
Indexes reflect coverage decisions made by two companies for commercial products. Their widespread use as a proxy for scholarly worth in hiring and promotion is a feature of institutional practice rather than an intrinsic property of the research itself. Understanding how the proxy operates is nonetheless valuable, because it can prevent avoidable harm to careers. It is equally valuable to maintain the distinction between navigating a measurement system competently and mistaking that system for the quality it is intended to measure.
References
- Clarivate. (2023). Announcing changes to the 2023 Journal Citation Reports. https://clarivate.com/academia-government/blog/clarivate-announces-changes-to-the-2023-journal-citation-reports-release/