2024 Journal Citation Reports Roundup

Lippincott publishes journals in 68 Web of Science® categories. Including all publishers, the average JIF fell in 65 of those 68 categories, with declines as high as 30% in Infectious Disease. Only Nuclear Science and Technology (+9%) and Oncology (+4%) saw the average JIF increase. The average JIF for all 68 categories decreased from 3.4 to 2.9 (-14%). 

What happened to the Journal Impact Factors since 2005?

Most conversations around editorial strategy tend to focus on the denominator of the JIF formula, since it is driven by editorial strategy, i.e., the “what,” “when,” and “how much” a journal publishes. Consequently, the tendency is to ascribe any change in JIF to a corresponding change in strategy – if the JIF went down, then the strategy must have been flawed or something must have gone wrong. The numerator, however, is as significant as the denominator, and unlike the denominator is driven by factors beyond the control of the journal, largely the overall output of research in a particular category. Why did the JIFs practically all drop? Because overall output in STM publications has dropped (Figure 1), and less publications means less citations, and less citations means smaller numerators, hence, lower JIFs. 

To some extent, journals have been spoiled by consistently growing research output for almost 20 years. If you became an editor in 2005, you have never seen a decline in research output until 2022. That growth effectively created JIF inflation and contributed to a growing perception that JIFs should always go up, with little reason to question the drivers causing that growth. After all, if the JIF improved, it must have been the result of a successfully executed editorial strategy.

Is a decline in the Journal Impact Factor always bad?

It’s important to recognize that the JIF’s value is a relative measure when compared to other journals in the same category. The JIF by itself provides no value. A commonly asked question online, “Is a JIF of 5 good?” In Oncology it wouldn’t crack the top 60; in nursing, it would rank number 2.

Traditionally, we use category rankings to assess how journals in the same field compare. However, this year naturally provided further confusion because of Clarivate changes. In the 2024 JCR, Clarivate introduced unified rankings, meaning that for the first time, titles in the same category, but different editions (e.g., SCIE, ESCI, SSCI) were combined into a single ranking. The upshot of this (plus the introduction of ties) meant that it was difficult to compare individual journal rankings to previous years. Combining the editions also meant that for most categories, the number of titles increased. As a result, we saw journals with lower JIFs, and lower rankings, but improved quartiles. If your journal ranking went from 20 to 30, but you moved from the 2nd quartile to the 1^st, did your journal do better or worse than last year?

Embracing Journal Impact Factor percentile instead

To try and make sense of the ranking changes, it may be beneficial to focus instead on JIF percentile – the percentage of journals in your category with a lower JIF. This establishes a more universal metric to measure a journal’s relative performance. In fact, Clarivate's intent was for JIF Percentile to be used to compare journals across different categories. If the JIF goes up or down (often driven as we’ve established by external factors), the JIF Percentile can indicate if the journal’s relative quality has shifted correspondingly. In many cases, JIF Percentile remains steady, despite the year-to-year fluctuations of the JIF itself.

Conclusion

The JIF serves two primary purposes for most journals: a marketing tool to attract submissions, and as a measure of a journal’s relative quality. For authors, who largely interact with JIF as a marketing tool, it would help them and journals to understand the mechanisms that affect the JIF and to expand their assessments beyond a single number that is too often placed at the forefront of journal promotion. For journals, it’s important to view the JIF within its proper context, and not be distracted by an emotional response to a number rising or falling. 

The JIF is neither good nor bad; it is a mathematical formula. Our overreliance on it and the conclusions we have drawn from it are understandably under scrutiny. However, used as one of many metrics to derive a complete picture of a journal's standing, it can still provide insight to inform a journal’s strategy.