Indicator that measures the frequency with which the article of a magazine has been quoted, on average, in a given year. It refers to journals and quantifies the echo that their content has in the scientific and academic world, helping to evaluate the relative importance of a magazine, especially if it is compared to others in the same scientific field.
In the Journal Citation Reports (JCR) is calculated by dividing the number of citations for the current year of articles published in the previous two years by the total number of articles published in those two years. It is calculated annually in two editions, Science and Social Sciences Edition.
Examples: to determine the impact factor of a magazine during the year 2007:
Often the validity of the impact factor as a quality index has been questioned. Some of the points to take into account in this regard are:
