Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Otolaryngol Head Neck Surg. 2011 Jul;145(1):15-7. doi: 10.1177/0194599811406648. Epub 2011 Apr 26.
Impact factor (IF) consists of reporting the number of references an average article in a given journal receives over a 2-year period. Despite several valid criticisms, IF has become an important component of academic advancement. The authors sought to investigate the possible relationship between size of specialty field and IF. The top 10 journals of 13 specialty fields were selected based on IF as reported by Journal Citations Reports on the Web of Science. Specialty field population was obtained from the American Board of Medical Specialties. A highly positive correlation (r = 0.9) was noted with smaller fields (eg, otolaryngology) having lower IFs. To overcome this population bias, a percentile-based impact factor (PIF) may be used where the top journal within a field is given 100%, the worst 0%, and all other journals' IFs are proportionately scaled in between the 2 extremes. PIF acts to "level the playing field," allowing between-specialty field comparisons.
影响因子（IF）的计算方法是，统计某一特定期刊在过去两年内发表的文章的平均被引次数。尽管存在一些合理的批评，但 IF 已经成为学术发展的重要组成部分。作者试图研究专业领域规模与 IF 之间可能存在的关系。根据 Web of Science 上 Journal Citations Reports 报告的 IF，选择了 13 个专业领域排名前 10 的期刊。专业领域的规模从美国医学专业委员会获得。研究发现，领域越小（例如耳鼻喉科），IF 越低，相关性非常高（r = 0.9）。为了克服这种人口偏见，可以使用基于百分位的影响因子（PIF），其中该领域排名最高的期刊得 100%，排名最差的得 0%，其他期刊的 IF 则在这两个极端之间按比例调整。PIF 起到了“公平竞争”的作用，允许在不同专业领域之间进行比较。
