The association between impact factors and language of general internal medicine journals.

BACKGROUND We sought to determine the associations between journal country of origin and language and journal impact factor of general medicine journals. METHODS For each "Medicine, General and Internal" journal listed in the Institute for Scientific Information (ISI) Journal Citation Reports (JCR), the 2003 impact factor, language (ie, English, multiple languages [including English], or non-English), and country of origin (ie, US or non-US) were determined. The mean log impact factors of the journals by language, country of origin, and a combination of country of origin and language were compared. RESULTS Of the 102 "Medicine, General and Internal" journals listed in the ISI JCR, 41 (40%) were published in the US and 83 (81%) were published in English. English-language journals had a significantly greater 2003 mean log impact factor than non-English journals and journals originating in the US had a significantly greater impact factor than journals originating elsewhere. However, the mean log impact factor of English-language journals originating in the US did not differ significantly from that of English-language journals originating elsewhere. CONCLUSION Journal impact factor is more associated with journal language (ie, English versus non-English), rather than journal country of origin.