Analysis of h-index and other bibliometric markers of productivity and repercussion of a selected sample of worldwide emergency medicine researchers Òscar Miró, 1,2 Pablo Burbano, 2 Colin A Graham, 3 David C Cone, 4 James Ducharme, 5 Anthony F T Brown, 6 Francisco Javier Martín-Sánchez 1,7 ABSTRACT Objective To explore bibliometric markers in a worldwide sample of emergency physician investigators to define global, continental and individual patterns over time. Methods We evaluated the number of papers published, citations received, cumulative impact factor and h-index of editorial board members of six international emergency medicine journals. We calculated the individual values for every year of each author’s career to evaluate their dynamic evolution. We analysed the results by researcher world area and growth rate. Results We included 107 researchers (76 American, 21 European and 10 Australasian; 46 slow-rate -group C-, 43 medium-rate -group B- and 18 fast-rate growth -group A-). The median experience was 18 (IQR: 12) years, without subgroups differences. Dynamic analysis over time showed good fit with quadratic function in all individual researchers and for all bibliometric markers (R 2 : 0.505–0.997), with the h-index achieving the best R 2 . The combined analysis of the h-index of the 107 investigators also fit the quadratic model (R 2 =0.49). Analysis by predefined continental and growth-rate subgroups allowed defining specific patterns (R 2 between 0.46–0.54 and 0.80–0.86, respectively): by continents, American researchers’ h-index increased 0.632 points per year, European 0.417 and Australasian 0.341; by growth rate, researchers from group A, B and C increased 1.239, 0.683 and 0.320, respectively. Conclusions Dynamic analysis of every individual author indicator over time has a very good fit with a quadratic model, with the h-index achieving the best R 2 . It is also possible to construct models based on continent and rate of growth that could help to predict future expected outcomes of researchers in a particular subgroup and to classify new emerging researchers by growth rate. INTRODUCTION The evolution of research in emergency medicine (EM) has been extensively analysed in recent years, and has shown a gradual increase in productivity 1–5 in parallel with the global growth observed in research activity and scientific production in the last decades. 6 Some bibliometric markers have served to better describe the evolution of research and researchers. Among these, two have gained wide popularity. The impact factor (IF), defined by Garfield, 7 estimates the quality of journals in which research is published. According to the definition, the IF (which is calculated yearly) for a journal cor- responds to the ratio of citations received by that journal during 1 year regarding papers published in the two previous years divided by the number of citeable articles published during these two previ- ous years. On the other hand, the h-index, defined by Hirsch, 8 estimates the relevance of researchers and is calculated as the number of articles that have been cited at least that number of times (eg, an h-index of 10 means that the author has 10 papers that have been cited at least 10 times each). Both bibliometric markers are based on the number of papers published and citations and, although they are quantitative in essence, they are usually also used as a proxy of quality, assuming that the greater the number of citations, the better the quality of the paper. Key messages What is already known on this subject? The evolution of research in emergency medicine (EM) has been extensively analysed in recent years, showing that productivity has gradually increased, in parallel with the global growth observed in research activity and scientific production in recent decades. Nonetheless, no work to date has analysed the evolution of bibliometric indicators of emergency physicians (EPs) involved in research, and the evolution of their research careers. A pilot study evaluated the dynamics of research output of 24 Spanish EPs and showed that it is possible to model changes in researcher bibliometric indicators over time that, in turn, could be used in the future to compare the behaviour of these research indicators with those of other research groups. What this study adds? Data obtained in this work show that it is possible to construct individual and group curves of career trajectories for EPs conducting research. This allows a better understanding of research activity and scientific impact in the field of EM worldwide and enables future comparisons with other groups of investigators and future generations of EP researchers. To cite: Miró Ò, Burbano P, Graham CA, et al. Emerg Med J 2017;34:175–181. 1 Editor in Chief, Emergencias, Barcelona, Spain 2 “Emergency Department, Hospital Clínic, Emergencies: Processes and Pathologies” Research Group, IDIBAPS, Barcelona, Spain 3 Editor in Chief, European Journal of Emergency Medicine, Hong Kong, China 4 Former Editor in Chief, Academic Emergency Medicine, New Haven, Connecticut, USA 5 Editor in Chief, Canadian Journal of Emergency Medicine, Hamilton, Ontario, Canada 6 Former Editor in Chief, Emergency Medicine Australasia, Brisbane, Australia 7 Associate Editor, Emergencias, Madrid, Spain Correspondence to Dr Òscar Miró, Emergency Department, Hospital Clínic, Villarroel 170, Barcelona 08036, Catalonia, Spain; omiro@clinic.cat Received 19 March 2016 Revised 28 July 2016 Accepted 1 August 2016 Published Online First 25 August 2016 Original article 175 Miró Ò, et al. Emerg Med J 2017;34:175–181. doi:10.1136/emermed-2016-205893 on December 15, 2021 by guest. Protected by copyright. http://emj.bmj.com/ Emerg Med J: first published as 10.1136/emermed-2016-205893 on 26 August 2016. Downloaded from