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Table 1 General characteristics of the sample of study

From: Global collaborative networks on meta-analyses of randomized trials published in high impact factor medical journals: a social network analysis

Characteristic Number (%)
Total number of articles 736 (100)
Articles per journala  
   BMJ 289 (39.3)
   The Lancet 132 (17.9)
   JAMA 113 (15.3)
   Arch Intern Med 112 (15.2)
   Ann Intern Med 70 (9.5)
   New Engl J Med 13 (1.8)
   PLoS Med 7 (0.9)
Citations per journalb  
   BMJ 37,930 (29.0)
   The Lancet 34,911 (26.7)
   JAMA 25,273 (19.3)
   Ann Intern Med 13,381 (10.2)
   Arch Intern Med 11,945 (9.1)
   New Engl J Med 6,992 (5.3)
   PLoS Med 212 (0.1)
Articles per period of publication  
   1985 to 1989 3 (0.4)
   1990 to 1994 53 (7.2)
   1995 to 1999 140 (19.0)
   2000 to 2004 166 (22.6)
   2005 to 2009 231 (31.4)
   2010 to 2012 143 (19.4)
Country of publication (first author)c  
   USA 214 (29.1)
   UK 207 (28.1)
   Canada 94 (12.8)
   Australia 36 (4.9)
   Switzerland 26 (3.5)
   France 26 (3.5)
   Denmark 20 (2.7)
   Italy 20 (2.7)
Number of authors per paper  
   1 41 (5.6)
   2 to 3 166 (22.5)
   4 to 6 297 (40.3)
   > 7 232 (31.5)
  1. aPLOS Medicine has been published weekly online since 19 October 2004.
  2. bInformation refers to the total citations received by all the papers published in a given journal (for example, 289 papers published in BMJ received a total of 37,930 citations).
  3. cInformation was incomplete for some records. We used country data of the first author in 704 out of 736 papers, while for 32 papers this information was retrieved from the correspondence address.