Journals that are indexed starting with a volume other than the first volume will not get an impact factor until they have been indexed for three years.
publishes cutting-edge articles in biomedical sciences to cover a broad range of topics that move the pharmacological field forward.
It is frequently used as a proxy for the relative importance of a journal within its field; journals with higher impact factors are often deemed to be more important than those with lower ones.
The impact factor was devised by Eugene Garfield, the founder of the Institute for Scientific Information (ISI).
Hence the commonly used "JCR Impact Factor" is a proprietary value, which is defined and calculated by ISI and can not be verified by external users.