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CHEM 210: Organic Chemistry

Tools to Measure Journal Impact (Impact Factor)

About Journal Impact

Impact Factor - What is it? Why use it?

The impact factor (IF) is a measure of the frequency with which the average article in a journal has been cited in a particular year. It is used to measure the importance or rank of a journal by calculating the times it's articles are cited.

How Impact Factor is Calculated?

The calculation is based on a two-year period and involves dividing the number of times articles were cited by the number of articles that are citable.

Calculation of 2010 IF of a journal:

A = the number of times articles published in 2008 and 2009 were cited by indexed journals during 2010.

B = the total number of "citable items" published in 2008 and 2009.

A/B = 2010 impact factor 

Questioning the Impact Factor

Greenwood, D. C. (2007). Reliability of journal impact factor rankings. BMC Medical Research Methodology, 7(48), 48.

Howard, J. (2009). Humanities journals confront identity crisis. The Chronicle of Higher Education, 55(19), A1.

Satyanarayana, K. & Sharma, A. (2008). Impact factor: Time to move on. The Indian Journal of Medical Research, 127(1), 4-6.

Seglen, P. O. (1997). Why the impact factor of journals should not be used for evaluating research. British Medical Journal, 314(7079), 498-502.

About the H-index

The h-index is an index to quantify an individual’s scientific research output (J.E. Hirsch)  
The h-index is an index that attempts to measure both the scientific productivity and the apparent scientific impact of a scientist. The index is based on the set of the researcher's most cited papers and the number of citations that they have received in other people's publications (Wikipedia)  A scientist has index h if h of [his/her] Np papers have at least h citations each, and the other (Np − h) papers have at most h citations each.