Anaesthesiology research in the European Union and the European Free Trade Association: An overview from 2001 to 2015.

Background: Publication performance in anaesthesiology hints at research activity and attractiveness for a particular centre or country for anaesthetists.

Objective: The aim of this retrospective bibliographic study is to compare the publication performance of anaesthesiology departments within the countries of the European Union (EU) and European Free Trade Association (EFTA) combined. Outcome measures were the number of publications, the number of original articles, the average impact factor and the number of publications and average impact factor per million inhabitants.

Methods: Articles from anaesthesiology departments within the EU and EFTA countries published between 1 January 2001 and 31 December 2015 were included. Articles were electronically imported from Medline into a database and linked to anaesthesiology departments according to the authors' affiliations. Publication performance was assessed for 2001 to 2005, 2006 to 2010, 2011 to 2015 and 2001 to 2015.

Results: From 2001 to 2015, the absolute number of articles increased from 10 513 to 19 037 (+81%), whereas the number of original research articles decreased from 3786 to 1563 (-58%). Germany had the most publications (8948) with 1967 of these being original articles. Denmark achieved not only the highest average impact factor per million inhabitants (319.9) but also the most articles per anaesthesiologist (1.46), and per million habitants (105.7). Countries which moved up the income scale to a higher income class also increased the number of publications.

Discussion: In the EU and EFTA countries, the total number of publications increased from 2001 to 2015, but the number of original research articles fell by more than 50%.

Conclusion: Between 2001 and 2015, in the EU and EFTA countries, the number of publications increased, whereas the number of original articles decreased. Germany published most, but Denmark had most publications per anaesthesiologist and per capita, and also achieved the highest impact factor per article.