The Evolving Trends in the Impact Factor of Plastic Surgery Journals: A 22-Year Analysis.

[BACKGROUND] The journal impact factor (IF) is one of the most widely adopted metrics to assess journal value. We aimed to investigate the trends in the IF and ranking of plastic surgery journals (PSJs) over a 22-year period.

[METHODS] The Journal Citation Report 2018 was used to identify all journals within the field of plastic surgery from 1997 to 2018. We analyzed the IF of PSJs and that of the category surgery.

[RESULTS] A total of 34 PSJs were identified. The mean IF increased from 0.584 (median, 0.533) in 1997 to 1.58 (median, 1.399) in 2018 (P < 0.0001). Over the same time, the median IF of the journals in the category surgery increased from 0.914 to 1.883. The mean journal IF percentile of PSJs within surgery remained fairly stable (P = 0.999). A strong positive correlation was identified between the IF of PSJs and both the 5-year IF (r = 0.943, P < 0.0001) and the immediacy index (r = 0.736, P < 0.0001). The percentage of self-citations across the study period was fairly stable at a mean of 19.2%. A weak positive correlation was found between the IF and the percentage of self-citations (r = 0.171, P < 0.0001).

[CONCLUSIONS] The mean journal IF in PSJs has been trending upward over the last 22 years. Ranking of PSJs IF within the category surgery has remained unchanged. The self-citation rate has been fairly stable and correlated weakly with the IF. A strong positive correlation exists between the IF and both the immediacy index and the 5-year IF.