Increasing dominance of English in publications archived by PubMed

English is becoming the international language in numerous fields of human civilization. We sought to evaluate the extent of use of English in the field of biomedical publications. We searched in PubMed for the number of articles written in the 57 indexed languages, during each one of the four past 10-year periods. The extent of use of English as the publication language of articles included in PubMed has gradually risen from 62.3% of the total number of indexed articles between 1967-1976, to 74.0% between 1977-1986, 83.4% between 1987-1996, and reached 89.3% in the period between 1997-2006. The percentage of articles written in each one of the other languages was less than 1.6% for the period of 1997-2006. Apart from English, only the percentage of articles written in Chinese has risen between 1967-1976 and 1997-2006 (from 0.05% to 1.49%). In conclusion, the dominance of English in biomedical publications archived by the most commonly used database is impressive and increasing. This fact may have several consequences, favourable or not, in various aspects of scientific production.