The Nature, published every week, has been rated as the number one multi-disciplinary science journal for the second year running, based on impact factor.
It also has got the highest Eigenfactor, an alternative measure of journal impact. In a separate indicator of excellence, Nature has also been named the ‘journal of the century’ by the BioMedical & Life Sciences Division (DBIO) of the Special Libraries Association (SLA). The award recognises Nature as the most influential journal of the last 100 years (1909-2009).
With an impact factor of 31.434, it has improved upon its last year’s value of 28.751. The Science journal, published by the American Association for the Advancement of Science, comes second with an impact factor of 28.103.
The impact factor is a measure of the frequency with which the average article in a journal has been cited by other papers, including those that in the same journal in which it was published.
Impact factor is a measure to estimate a journal’s relative importance in a particular field.
Rating of journals based on impact factor is not without criticism, however. Critics say the process of arriving at the impact factor is flawed. The performance of researchers is very often evaluated based on the number of papers published in high-impact journals. This, in turn, forces researchers to publish their papers in such journals, which would not necessarily be widely read by peers. This is seen as the biggest disadvantage of this rating methodology.
In the case of Eigenfactor, journals are considered to be influential if they are cited often by other influential journals. The Eigenfactor score of a journal provides an estimate of the percentage of time that a person spends his time with a particular journal.