Citations calculations can produced variable results says study

Science News: Although the impact of a published study can be measured many ways, the most common tactic has been to tally how often, over the years, others cite the study in their published works. A small industry has emerged over the past half century to quantify these citations. A new analysis has now compared citation counts from three different companies and shown that their performance differs. At least when it comes to published biomedical studies, some citation indices may make a given piece of work appear substantially more—or less—influential than do others. Related Links Comparisons of citations in Web of Science, Scopus, and Google Scholar for articles published in general medical journals The journal impact factor denominator: Defining citable (counted) items