Department of Medicine, Alfa Institute of Biomedical Sciences, Athens, Greece.
Intern Med J. 2010 Aug;40(8):587-91. doi: 10.1111/j.1445-5994.2010.02247.x.
Whether the journal impact factor (JIF) indicator reflects the number of citations to an average article of a journal in different subject categories is controversial. We sought to further investigate this issue in general and internal medicine journals.
We selected to evaluate three journals of the above subject category, in each of three different JIF levels (high: 15.5-28.6, moderate: 4.4-4.9 and low: 1.6). Using the Scopus database, we retrieved the original research articles (after detailed screening) and review articles (as classified by Scopus) that were published in the selected journals in 2005 along with the number of citations they received in 2006 and 2007. We pooled the citations for articles of the same type in journals with the same JIF level into distinct variables.
There was no marked association between the distribution of citations per article published in general medical journals and their JIF. All distributions studied were skewed to the right (higher number of citations). Specifically, 16-22% of the original research articles accounted for 50% of the total citations to this type of article for all three categories of studied journals; 34-37% of original research articles accounted for 75% of citations. The respective values for review articles were 12-18% and 29-39%.
The distribution of citations received by articles published in high, moderate and low impact factor journals in clinical medicine seems similar. The JIF is not an accurate indicator of the citations the average article receives; articles published in low impact factor journals can still be highly cited and vice versa.
期刊影响因子（JIF）指标是否反映了不同学科类别期刊中平均文章的被引次数存在争议。我们试图在一般和内科学期刊中进一步研究这个问题。
我们选择评估三个上述主题类别的期刊，每个类别分为三个不同的 JIF 级别（高：15.5-28.6、中：4.4-4.9 和低：1.6）。使用 Scopus 数据库，我们检索了 2005 年在选定期刊上发表的原始研究文章（经过详细筛选）和综述文章（按 Scopus 分类），以及它们在 2006 年和 2007 年获得的引用次数。我们将同一 JIF 级别的期刊中相同类型的文章的引用次数汇总到不同的变量中。
一般医学期刊发表的文章的被引次数分布与其 JIF 之间没有明显的关联。所有研究的分布都是偏态的（引用次数较高）。具体来说，对于所有三个研究类别的期刊，16-22%的原始研究文章占此类文章总引用量的 50%；34-37%的原始研究文章占引用量的 75%。综述文章的相应值分别为 12-18%和 29-39%。
在临床医学中，高、中、低影响因子期刊发表的文章的被引次数分布似乎相似。JIF 不是平均文章获得的引用次数的准确指标；发表在低影响因子期刊上的文章仍然可以获得高度引用，反之亦然。
