Top 20 nations in psychiatry and psychology

The data above were extracted from the Essential Science Indicators database of Thomson Reuters. This database, currently covering the period January 2000 through to December 2010, surveys only articles (original research reports and review articles) in journals indexed by Thomson Reuters. Articles are assigned to a field based on the journals in which they were published and the Thomson Reuters journal-to-field scheme. Papers published in multidisciplinary journals are selectively assigned to their appropriate fields.

Both articles tabulated and citation counts to those articles are for the period indicated.

Here, the ranking in psychiatry and psychology is by citations per paper – among nations whose papers collected at least 5,000 or more citations during the period – to reveal weighted influence. For articles with multiple authors from different nations, each nation receives full, not fractional, publication and citation credit.

Essential Science Indicators lists nations ranked in the top 50 per cent for a field over a given period, based on total citations. In psychiatry and psychology, 87 nations are listed, meaning 174 were surveyed.

Thirty-one nations collected 5,000 or more citations to their papers. The world average in citation impact for the field was 11.26 during the period, so the top nine listed above surpassed that mark.

For further information on Thomson Reuters Essential Science Indicators, see http://science.thomsonreuters.com/products/esi/