Did you know that a journal with a high Impact Factor could actually be under investigation?
Selecting the right journal is a critical decision for researchers. Many choose journals based solely on Impact Factor, but being aware of a journal’s editorial integrity and trustworthiness is equally important.
Clarivate offers two primary platforms—JCR and MJL—that provide complementary information for different purposes. Let’s explore the differences between them and understand why checking both is essential.
What Are JCR and MJL?
JCR (Journal Citation Reports)
JCR is Clarivate’s premium, subscription-based service that focuses specifically on citation metrics. It provides the following information for journals indexed in Web of Science:
- Impact Factor (the primary measure of a journal’s influence)
- Quartile Ranking (Q1, Q2, Q3, Q4)
- Citation Data (citation statistics)
- Various Bibliometric Indicators
JCR is primarily used to evaluate journal quality and prestige based on citation performance.
MJL (Master Journal List)
MJL is Clarivate’s freely accessible comprehensive database that lists all journals included in their products:
- Web of Science Core Collection
- ESCI (Emerging Sources Citation Index)
- Other Clarivate indexes
Beyond basic indexing information, MJL crucially displays journal status warnings and editorial concerns.
Warning Signs Displayed in MJL
1. Journals Under Investigation for Editorial Misconduct
What does this mean?
Clarivate is investigating the journal’s editors or publishers for suspected unethical activities.
Examples include:
- Coercing authors into self-citation
- Manipulating the peer review process
- Demanding excessive fees from authors
- Using fake peer reviewers
2. Suppressed Journals (Temporarily Suspended from Indexing)
What does this mean?
The journal has been temporarily removed from Web of Science due to serious policy violations.
What happens?
- After the investigation, the journal will either be reinstated or permanently removed
- New articles are not indexed during this period
- However, previously published articles may remain
3. Journals with Citation Stacking Issues
What does this mean?
Multiple journals are artificially inflating their Impact Factors by citing each other at abnormally high rates.
How does it work?
This is a coordinated fraudulent scheme where journals systematically cite each other’s articles to manipulate metrics. For example, Journal A and Journal B cite each other excessively to boost both their Impact Factors.
4. Historical Changes in Journal Coverage
What does this mean?
A record of which index the journal was previously in and when changes occurred.
Examples:
- Transfer from SCIE to ESCI
- Complete de-indexing
- Transfer from one category to another
This helps understand the journal’s quality trajectory—whether it’s improving or declining.
Key Differences: JCR vs MJL
| Feature | JCR | MJL |
|---|---|---|
| Access | Subscription required | Completely free |
| Primary Focus | Citation metrics | Journal status |
| Impact Factor | ✓ Detailed | ✗ Not displayed |
| Quartile Ranking | ✓ | ✗ |
| Warning Signs | ✗ | ✓ |
| Investigation Status | ✗ | ✓ |
| Historical Data | Limited | ✓ Complete |
Critical Insight for Researchers
MJL serves as a transparency tool showing a journal’s “health status,” while JCR is purely a metrics platform.
Important fact:
A journal may have an Impact Factor in JCR while simultaneously displaying warning signs in MJL indicating an ongoing investigation. In such cases, making decisions based solely on Impact Factor is risky.
Real-World Example
Consider a journal with:
- JCR Impact Factor: 5.2 (Q1)
- MJL status: “Under investigation for editorial misconduct”
What could happen if you submit a paper to this journal?
- The journal could be suppressed after the investigation concludes
- Your paper could be removed from the index
- This publication could become questionable on your CV in the future
What Should We Do?
Step 1: Check Both Platforms
Before submitting your manuscript, check both platforms because they provide complementary information.
Check JCR for:
- Impact Factor
- Quartile Ranking
- Subject Category
- Citation Trends
Check MJL for:
- Any warning signs
- Indexing status
- Historical changes
- Current coverage
Step 2: Avoid Journals with Warning Signs
If you see any warnings in MJL:
- Journal under investigation → Avoid
- Suppressed journal → Definitely avoid
- Citation stacking → Suspicious, look for alternatives
Step 3: Analyze Historical Trends
If a journal has:
- Dropped from SCIE to ESCI → Quality is declining
- Risen from ESCI to SCIE → Quality is improving
- Frequent index changes → Unstable
Why Is This More Important Now?
As Clarivate has enhanced its quality control measures and made investigation statuses publicly visible, MJL has become increasingly important.
In recent years:
- The number of predatory journals has increased
- Citation manipulation has become more sophisticated
- Cases of editorial misconduct have risen
Therefore, making decisions based solely on Impact Factor is no longer sufficient.
Quick Checklist: Before Selecting a Journal
Links and Resources
- JCR: https://jcr.clarivate.com/ (subscription required)
- MJL: https://mjl.clarivate.com/ (free)
- Web of Science: https://www.webofscience.com/
Summary
Impact Factor is an important metric, but it’s not the only consideration. A journal’s editorial integrity and ethical standards are equally important for your research career.
Remember:
- JCR = Shows metrics
- MJL = Shows integrity
- Both needed = Safe decision
Don’t rush your journal selection. Take a few minutes to check both JCR and MJL. It will protect the future of your research!
Caution: A high Impact Factor doesn’t always guarantee a safe journal. If you see warning signs in MJL, avoid that journal!
Citation
@online{abdus_samad2026,
author = {Abdus Samad, Md},
title = {JCR Vs {MJL:} {Which} {Should} {You} {Check} {When}
{Selecting} a {Journal?}},
date = {2026-02-06},
url = {https://www.drabdus.com/blog/2026/02/06/jcr-vs-mjl-difference-en/},
langid = {en}
}