This page provides information on citation metrics for Nature Reviews Microbiology. Data are collected annually for full calendar years. More information regarding the release of these data can be found here. Click here to download our quick reference guide to journal metrics.
Nature Portfolio is a signatory of the San Francisco Declaration on Research Assessment (see here for more information about our endorsement). We believe that Impact Factor is just one of a number of metrics that can be used to evaluate a journal, and a small number of highly cited papers can have a disproportionate effect on the mean number of citations per paper.
2021 Journal Metrics
On this page you will find a suite of citation-based metrics for Nature Reviews Microbiology which provides an overview of this journal. Because the median is not subject to the distortions from outliers, we have developed and provided the 2-year Median, derived from Web of Science data and defined as the median number of citations received in 2021 for articles published in 2020 and 2019. Brief definitions for each of the metrics used to measure the influence of our journals are included below the journal metrics. More information regarding the approach taken to derive the median citation can be found here. Article-level metrics are also available on each article page, allowing readers to track the reach of individual papers.
As described above, Nature Portfolio has produced the 2-year Median in the table below. All other data has been produced by Clarivate Analytics.
Journal metrics are based on the published output, thus those that are calculated from the output in multiple years will use a partial dataset for recently launched journals.
While the metrics presented here are not intended to be a definitive list, we hope that they will prove to be informative. The page is updated on an annual basis.
2 year Impact Factor (2021) - 78.297
5- year Impact Factor (2021) - 72.908
Immediacy index - 11.736
Eigenfactor® score - 0.05586
Article Influence Score - 20.852
2-year Median - 44
4,079,224 Downloads (in 2021)
23,435 Altmetric mentions (2021)
2-year Impact Factor:
The Journal Impact Factor is defined as all citations to the journal in the current JCR year to items published in the previous two years, divided by the total number of scholarly items (these comprise articles, reviews, and proceedings papers) published in the journal in the previous two years. (Courtesy of Clarivate Analytics)
5-year Impact Factor:
The 5-year journal Impact Factor, available from 2007 onward, is the average number of times articles from the journal published in the past five years have been cited in the JCR year. It is calculated by dividing the number of citations in the JCR year by the total number of articles published in the five previous years. (Courtesy of Clarivate Analytics)
The Immediacy Index is the average number of times an article is cited in the year it is published. The journal Immediacy Index indicates how quickly articles in a journal are cited. (Courtesy of Clarivate Analytics)
The Eigenfactor Score calculation is based on the number of times articles from the journal published in the past five years have been cited in the JCR year, but it also considers which journals have contributed these citations so that highly cited journals will influence the network more than lesser cited journals. References from one article in a journal to another article from the same journal are removed, so that Eigenfactor Scores are not influenced by journal self-citation. (Courtesy of Clarivate Analytics)
Article Influence Score:
The Article Influence Score determines the average influence of a journal's articles over the first five years after publication. It is calculated by multiplying the Eigenfactor Score by 0.01 and dividing by the number of articles in the journal, normalized as a fraction of all articles in all publications. This measure is roughly analogous to the 5-Year Journal Impact Factor in that it is a ratio of a journal's citation influence to the size of the journal's article contribution over a period of five years. (Courtesy of Clarivate Analytics)
The median number of citations received in the most recent full year for articles published in the preceding two years. Data from Web of Science was used; more information regarding the details of article categories and approach taken to derive the median citation can be found here. (Nature Portfolio Data)