Evaluation of the i10-Index in Plastic Surgery Research and its Correlation with Altmetric Attention Scores and Traditional Author Bibliometrics: An Evaluation of a Single Journal.

Although the Hirsch index (H-index) has become one of the most accepted measures of scholarly output, its limitations have led to the proposition of newer alternative metrics. The i10-index, notable for being easy to calculate and free to access, has potential, given its association with the power and ubiquity of Google. This study aims to evaluate the utility of the i10-index for plastic surgery research by examining its relationship with author bibliometrics and article metrics, including the H-index and Altmetric Attention Score (AAS).  Article metrics were extracted from articles published in the highest impact plastic surgery journal, Plastic and Reconstructive Surgery, over a 2-year period (2017-2019). Senior author bibliometrics, including i10-index and H5-index, were obtained from Web of Science. Correlation analysis was performed using Spearman's rank correlation coefficient (r ).  A total of 1,668 articles were published and 971 included. Senior author i10-index measurements demonstrated moderate correlation with times emailed (r  = 0.47), and weak correlations with H5-index, total publications, and sum of times cited with and without self-citations. The H5-index correlated very strongly with total publications (r  = 0.91) and sum of times cited (both r  = 0.97), moderately with average citations per item (r  = 0.66) and times emailed (r  = 0.41), and weakly with number of citations by posts, AAS, and times tweeted.  Although the i10 strongly correlates with the H5-index, it fails to prove superior to the H5-index in predicting the impact of specific research studies in the field of plastic surgery.