The impact factor of journals is a crucial academic publishing metric, serving as a measure of a journal’s influence and importance within its field. For you, as a researcher, and institutions alike, understanding this journal classification is essential for making informed decisions about where to publish and which journals to follow.
What is Impact Factor?
The Impact Factor was created by Eugene Garfield, the founder of the Institute for Scientific Information (ISI). Garfield first mentioned the idea of an impact factor in Science magazine in 1955.
In the early 1960s, Eugene Garfield with the help of Irving H. Sher created the Journal Impact Factor (JIF) to help select journals for the Science Citation Index (SCI). They developed this metric by re-sorting the researcher citation index into a journal citation index.
Initially, the Impact Factor was used internally by ISI to compile the Science Citation Index. In 1975, ISI began publishing the Journal Citation Reports (JCR), which included the Impact Factor calculations for journals.
How is the Impact Factor of Journals Calculated?
By calculating the average number of citations received by articles published in those journals over a set period of time, typically two years.
For example, the 2022 impact factor of journals is calculated as follows:
Journal Impact Factor (JIF) = A / B
Where:
- A = Total number of citations in a given year (e.g., 2023) to articles published in the previous two years (e.g., 2021 and 2022).
- B = Total number of citable items (articles, reviews, etc.) published in those same two years (2021 and 2022).
What Does the Impact Factor of Journals Tell a Researcher?
The impact factor of journals provides you with valuable insights into a journal’s influence and importance within its field. Here’s what the impact factor tells you:
1. Journal Quality: A higher impact factor generally indicates a more prestigious and influential journal in its discipline. This can help you identify high-quality publications for your work.
2. Citation Frequency: The impact factor reflects the average number of citations received by articles published in the journal over a specific period. This indicates how frequently the journal’s content is cited by other researchers.
3. Visibility and Reach: Journals with higher impact factors tend to have broader readership and greater visibility in the academic community. Publishing in these journals can increase the exposure of your research.
4. Research Influence: The impact factor of journals can serve as a proxy for the potential influence of research published in a particular journal. It suggests how impactful the average article in that journal might be.
5. Career Advancement: Publishing in high impact factor journals can be crucial for academic and professional advancement, often considered in tenure decisions, grant applications, and professional evaluations.
6. Comparative Tool: Researchers can use the impact factor to compare journals within the same field, helping them make informed decisions about where to submit their work.
However, it’s important to note that the impact factor has limitations. It doesn’t measure the quality of individual articles, and it can be influenced by factors such as the number of review articles a journal publishes. You should consider the impact factor alongside other metrics (e.g., SJR scores), and qualitative assessments when evaluating journals for your research.
What is a good impact factor?
The impact factor (IF) is a metric used to evaluate the influence and quality of academic journals by measuring the frequency with which their articles are cited. Generally, a higher impact factor indicates a more influential journal within its field. However, “good” impact factors vary significantly across different disciplines. For instance, in biochemistry, impact factors are often categorized as follows:
- Good: 2–4
- Great: 5–8
- Awesome: 9–14
- Excellent: Above 14
It’s important to note that these ranges are approximate and can vary based on specific research areas. Additionally, while impact factors provide insight into a journal’s citation frequency, they do not necessarily reflect the methodological quality or societal impact of individual articles. Therefore, when assessing research quality, it’s advisable to consider multiple metrics alongside the impact factor.
What are the Highest Impact Factor Journals
Some of the top impact factor journals include:
- Medical and Life Sciences
– CA-A Cancer Journal for Clinicians (254.7)
– The New England Journal of Medicine (91.245)
– The Lancet (79.321)
– Nature Reviews Molecular Cell Biology (94.444)
- Multidisciplinary Sciences
– Nature (50.5)
– Science (47.728)
- Physical Sciences
– Chemical Reviews (60.622)
– Nature Materials (43.841)
– Nature Nanotechnology (39.213)
- Environmental Sciences
– Energy & Environmental Science (38.532)
– Nature Geoscience (16.908) - Computer Science and Engineering
– IEEE Transactions: Systems, Man, and Cybernetics (13.451)
These top-tier journals represent the pinnacle of academic publishing, often featuring groundbreaking research and influential studies.
Academic Journal Impact: Beyond the Numbers
While the impact factor of journals is a valuable journal ranking, it’s important to consider other factors when evaluating academic influence:
- Field-specific considerations: Impact factors can vary significantly between different academic disciplines
- Citation patterns: Some fields have faster citation cycles than others, affecting impact factor calculations.
- Journal scope: Specialised journals may have lower impact factors but still be highly influential in their niche.
Conclusion
Understanding the impact factor of journals is crucial for researchers navigating the academic publishing landscape. While it’s a valuable metric, it should be considered alongside other factors when evaluating journal quality and influence. By staying informed about impact factors and their implications, researchers can make more strategic decisions about where to publish their work and maximise the visibility and impact of their research.