Impact Factor Defined
The Impact Factor is used to determine the relative importance of a journal within its field, journals with higher impact factors are deemed to be more important than those with lower impact factors.
Criticisms
The impact factor is dependent on the academic discipline and the speed at which papers get cited in a field. Some also take issue with the fact that many institutions place too much value on the impact factor since it is not entirely scientific or reliable.
How Impact Factors are Calculated
Impact Factors are calculated by dividing teh number of citations by the number of articles published in the two previous years. For example, an Impact Factor of 1.0 means that the articles published one or two years ago have been cited one time. More information can be found here.
Factors that Influence Impact Factors
Date of Publication:
Small vs. Large Journals:
Average Citation:
Review Articles:
Changing/Growing Fields:
Research vs. Clinical Journals:
Several publishers list the impact factor for some of their journal titles. In some cases, both the impact factor and rank-in category data are made available.
Produced by Elsevier®