Global trends of ERCP research in the last 25 years: A bibliometrics study

Purpose: Endoscopic retrograde cholangiopancreatography (ERCP) has been used in clinical practice for over 50 years. This study aims to investigate the current state of research in the field of ERCP. Methods: Web of Science database was searched using the term "ERCP" for articles published between 1994 and 2018. The total number of articles from the top 20 countries with the most published articles was determined. The top 5 countries were compared in terms of output per capita, number of articles published in top journals, cumulative impact factor (IF), and average IF. All annual data were subjected to time-trend analysis. The frequently used terms in the titles and abstracts of all articles were retrieved to conduct co-occurrence analysis to determine the research focus of ERCP. Results: A total of 9960 articles on ERCP were published between 1994 and 2018, of which 8778 articles were from the top 20 producing countries. There was a significant positive correlation between the output and GDP of each country (R = 0.870, P = .001). The United States of America (USA), Japan, Germany, Italy, and China were the top 5 producing countries with 3190 (32.0%), 868 (8.7%), 658 (6.6%), 512 (5.1%) and 488 (4.9%) articles published, respectively. The USA, Japan, Italy, and China were trending upwards in the total outputs and outputs per capita, while Germany were trending downwards. For average IF, Germany had a downwards trend, while the other 4 countries remained stable. Overall, the USA had the highest output per capita (97.5/10 million) and the highest average IF (6.454). China had the lowest output per capita (3.5/10 million) and average IF (3.125). The ERCP procedures for sphincter of Oddi dysfunction, the combination of ERCP, and laparoscopic cholecystectomy have been the research focus of ERCP. Conclusions: Except for Germany, research on ERCP will continue to increase in the top-producing countries. The outputs per capita and quality of articles from developed countries are higher than those from developing countries.