The significant yet short-term influence of research covidization on journal citation metrics

COVID-19 has emerged as a major research hotspot and trending topic in recent years, leading to increased publications and citations of related papers. While concerns exist about the potential citation boost in journals publishing these papers, the specifics are not fully understood. This study uses a generalized difference-in-differences approach to examine the impact of publishing COVID-19 papers on journal citation metrics in the Health Sciences fields. Findings indicate that journals publishing COVID-19 papers in 2020 received significantly higher citation premiums due to COVID-19 in 2020 and continued to benefit from the premium in 2021 in certain fields. In contrast, journals that began publishing COVID-19 papers in 2021 experienced weaker citation premiums. The citation premiums exhibit some negative spillover effect: Although the publication volume of non-COVID-19 papers also surged, these papers experienced insignificant or negative citation gains, even when published in the same journals as COVID-19 papers. COVID-19 papers published in high-impact journals brought higher citation premiums than those in low-impact journals in most fields, indicating a potential Matthew effect. These citation premiums can affect various citation-based journal metrics, such as our simulated impact factor and SCImago Journal Rank, to different degrees. Compared to the simulated impact factor, other normalized journal metrics are less influenced by citation premiums. The results highlight a “gold rush” pattern in which early entrants establish their citation advantage in research hotspots and caution against using citation-based metrics for research assessment.