Making an impact in nutrition and dietetics
The impact of a journal can be assessed in many ways; the most freqently used measure is its impact factor (IF). A journal’s IF is produced by the Institute for Scientific Information (ISI – now owned by Thomson Scientific) and published in the Journal Citation Report® in June each year. The IF calculation is based on the average number of times an article is cited in the two years following publication. To be more specific, the 2007 IF was calculated by dividing the number of citations that papers published in 2005 and 2006 received in 2007 by the number of papers published in 2005 and 2006. Citations to several formats are counted including original articles, reviews, editorials and notes, though not all document types are included as source items – i.e. in the denominator of the calculation – such as letters and editorials. An IF of 1.00 means that on average the articles published in the previous two years have been cited once.