The Journal Impact Factor (IF or JIF) is published annually by Clarivate Analytics (formerly Thomson Reuters) in the Journal Citation Reports (JCR) and is defined as the number of citations in the previous year (e.g. 2015 for the IF released in 2016) to the citations to articles published in the preceding 2 years (e.g. 2013-2014), divided by the number of articles published during that time. The Journal Impact Factor is a metric of excellence for a journal, it is not an article-level metric (article-level metrics are citations to a specific article, as well as altmetrics, tweetations, twimpact factor).
The Impact Factor is an increasingly controversial metric due its frequent misuse, e.g. administrators comparing the "raw" impact factor score across disciplines, as well as the intransparent procedures and arbitrary and slow journal selection procedures on the part of Thomson Reuters. This disadvantages journals in smaller disciplines such as medical informatics, which traditionally have less citations than for example multidisciplinary or general medicine journals. As one innovation, Thomson Reuters is now ranking journals by quartile (Q1, Q2, Q3, Q4), within their discipline. The impact factor has also been criticized for being subject to manipulation and the recent case of citation stacking / citation cartel leading to the exclusion of 3 medical informatics journals from the impact factor serves as a reminder of that (see below). (As an aside, we are proud of the fact that we are still the #1 MI journal in that category even if journal-level self-citations are excluded)
While we at JMIR discourage obsession over the journal impact factor (in particular if abused as proxy to assess the quality of individual articles), our ranking in the JCR is an important validation that even as small open access publisher we can compete with journals published by publishing giants.
For 10 years now, JMIR is consistently ranked in the first quartile (Q1) in both of it's disciplines, medical informatics (Q1, #2/20, 93rd percentile) and health services research (Q1, #5/87, 94th percentile).
JMIR mHealth and uHealth: 2.03 (unofficial impact factor, official IF expected in July 2017)
JMIR Serious Games: 1.8 (unofficial impact factor)
i-JMR: 1.5 (unofficial impact factor)
- What is the impact factor of your sister journal XY? Can I use the same impact factor as J Med Internet Res to advertise the importance of my work?
- JMIR Impact Factor 2016 (announcement on JMIR site)
- What are altmetrics, tweetations, twimpact factor (tw7)?