Bibliometric analysis of alternative performance metrics for peri-operative, critical care and pain medicine journals.
Traditional medical publication metrics, such as impact factor, have various well described limitations [1, 2]. Modern, alternative metrics, such as the Altmetric attention score (https://www.altmetric.com), provide scores for each publication using an automated algorithm representing a weighted count of the amount of attention for a research output from various sources. Sources include but are not limited to: news articles; blogs; policy documents; patents; engagements on social media platforms; and number of citations. We aimed to use the Altmetric attention score to derive a new performance metric comparable with impact factor, and we applied this metric to journals in peri-operative medicine, critical care and pain. This new metric, the Altmetric impact factor, encompasses the same denominator and timescale as impact factor, but uses the Altmetric attention score instead of number of citations as the numerator. Eighteen journals were selected based on their recent impact factor with six chosen from fields in peri-operative, critical care and pain medicine. Altmetric attention scores of all articles published in 17 journals during 2018 and 2019 were searched manually using the Altmetric website (www.altmetric.com) between April and June 2020. For the British Journal of Anaesthesia, Altmetric attention scores were retrieved from Dimensions (www.dimensions.ai) during January 2021. For the denominator, we included original articles, reviews of all types and guidelines. We excluded non-citable items such as editorials and correspondence. Normality of distribution of the cumulative Altmetric attention scores per article of all journals for 2018 and 2019 was tested using the Kolmogorov–Smirnov method. To correlate the Altmetric impact factor with the impact factor of the 18 journals, we used Spearman's rho test. The Altmetric impact factor of all journals was higher than the corresponding impact factor, except for the European Journal of Anaesthesiology. The mean (SD) Altmetric impact factor vs. impact factor of peri-operative, critical care and pain medicine journals was 27.813 (28.081) vs. 5.384 (1.387); 32.071 (19.945) vs. 9.197 (6.739); and 11.948 (5.955) vs. 3.94 (1.897), respectively. The overall mean (SD) Altmetric impact factor of the 18 journals was 23.944 (20.946), thus close to four-fold higher compared with the mean (SD) impact factor of 6.174 (4.493). Ranking the 18 journals by the Altmetric impact factor does not follow ranking by impact factor (Fig. 1). We found a positive correlation between Altmetric impact factor and impact factor (rs = 0.730, p = 0.001). Several studies report correlations between the Altmetric attention score or their sources (blogs, tweets or news etc.) with citations [3-5]. Comparisons of Altmetric attention score with impact factor are, however, very limited and, as yet, inconclusive [6, 7]. For journal level performance measurement based on social and mainstream news media, our novel performance metric is arguably more relevant than impact factor. Different rankings have previously been observed in peri-operative medicine journals by total and per article Altmetric attention score and by impact factor [3]. Altmetric attention score may be comparable to citations, but not to impact factor. Impact factor includes a denominator comprising the number of original articles, reviews and guidelines [1]. Altmetric impact factor similarly calculated could be compared with the traditional impact factor. Another issue is that the Altmetric attention score represents the attention for an output in real time but does not follow the increase rate of citations in the medium or long term [8]. Altmetric do not offer journal level metrics or ranking. This becomes feasible by implementing the Altmetric impact factor metric outlined here. Further studies are required in more journals and disciplines. In conclusion, the proposed Altmetric impact factor metric follows a different pattern of journal ranking and highlights the attention given to journals by the academic community from means other than citations in a 2-year period following publication alone.
Read more