The Distribution of the H‐index Among Academic Emergency Physicians in the United States

Abstract

Background: Hirsch's h-index (h) attempts to measure the combined academic impact and productivity of a scientist by counting the number of publications by an author, ranked in descending order by number of citations, until the paper number equals the number of citations. This approach provides a natural number or index of the number of publications and the number of citations per publication. H was first described in physics and was demonstrated to be highly predictive of continued academic activity, including recognized measures of scientific excellence such as membership in the National Academy of Sciences and being a Nobel laureate. Citation rates, research environments, and years of experience all affect h, making any comparisons appropriate only for scientists working in the same field for a similar time period. The authors are unaware of any report describing the distribution of h among academic emergency physicians (AEPs).

Promoting Stewardship of Academic Productivity in Emergency Medicine: Using the H‐index to Advance Beyond the Impact Factor

“…1 Electronic indexing systems have made it very easy to calculate how often any given scholarly paper has been cited by other scholarly products, and since we favor quantifying what we can easily measure, 2 a number of citation metrics have been developed that purport to assess the quality of journals, papers, and authors, including the h-and m-indices, as well as country or language-stratified first-and second-generation citation reports and an evolving series of vendor products like Faculty of 1000, Researcher ID, Google Scholar, SciVerse, SCOPUS, ORCID, Gopubmed, and Microsoft Academic Search. 3 In this issue of Academic Emergency Medicine, DeLuca et al 4 present what we believe is the first datadriven look at the h-index as a measure of the academic productivity of emergency physicians. Hirsch first proposed the h-index in the field of physics and also suggested the m-index for younger authors.…”

“…5 As DeLuca et al note, there are a number of attractive features to h-index. 4 For example, it is fairly resistant to self-citation, at least at the high end; if you cite your first paper in your second paper, your h-index jumps from 0 to 1, but it would be difficult to artificially inflate your h-index once it is greater than perhaps 10 by citing yourself. 7,8 Also, a single frequently cited paper will not increase one's h-index, nor will a large number of rarely cited papers; a researcher must consistently produce papers that are frequently cited to increase his or her h-index.…”

“…DeLuca et al attempted to address the role of the longevity of authors in their paper, examining increases in h-index per year as a way to perhaps gauge sustained productivity. 4 Unlike impact factor, which looks only at citations from the 2 years prior to the year being examined (e.g., citations from 2010 and 2011 are used in calculating a journal's 2012 impact factor), h-index is simply cumulative, and an author's or journal's h-index can never go downeven if that author ceases writing papers or the journal ceases publication. This may make h-index a better gauge of the entirety of a scholar's career or journal's history than impact factor, but a less useful measure of recent productivity.…”

“…These assumptions do not hold up to scrutiny, for a number of reasons, 15,16 and we may be seeing the beginning of a trend away from the use of impact factor. 17 DeLuca et al 4 hint that perhaps h-index can fill this void, as it was specifically designed to assess the career output of individual scholars.…”

“…As DeLuca et al note, understanding this distribution within each specialty is an important first step in using the h-index to quantitatively assess and compare academic scholarly productivity within the context of our peers. 4 Whereas 85% of academic ED faculty have hindices less than or equal to 6, the top 5th percentile have h-indices of 13 or greater. Furthermore, only 10% of academic faculty increase their h-indices by more than 0.5 points per year.…”