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.
- The aggregate Immediacy Index indicates how quickly articles in a subject
category are cited.
The Immediacy Index is calculated by dividing the number of citations to articles
published in a given year by the number of articles published in that year.
Because it is a per-article average, the Immediacy Index tends to discount
the advantage of large journals over small ones. However, frequently issued journals
may have an advantage because an article published early in the year has a better
chance of being cited than one published later in the year. Many publications
that publish infrequently or late in the year have low Immediacy Indexes.
For comparing journals specializing in cutting-edge research, the immediacy
index can provide a useful perspective. The example below shows journals ranked by the Immediacy Index in the category of Developmental Biology.
Here is the calculation for the immediacy index number.