Table 2.
Top 10 most productive countries/regions and institutions.
| Rank | Country/Regions | Year | Count | Centrality | Institutions | Year | Count | Centrality |
|---|---|---|---|---|---|---|---|---|
| 1 | USA | 2012 | 1573 | 0.36 | Univ Pittsburgh | 2012 | 162 | 0.37 |
| 2 | People’s Republic of China | 2012 | 590 | 0.08 | Univ Maryland | 2012 | 103 | 0.26 |
| 3 | Germany | 2012 | 240 | 0.03 | Univ Texas Hlth Sci Ctr Houston | 2012 | 80 | 0.06 |
| 4 | Japan | 2012 | 158 | 0.01 | Uniformed Serv Univ Hlth Sci | 2012 | 75 | 0.1 |
| 5 | England | 2012 | 120 | 0.1 | Univ Michigan | 2013 | 72 | 0.11 |
| 6 | France | 2012 | 111 | 0.05 | Univ Colorado | 2012 | 67 | 0.04 |
| 7 | Italy | 2012 | 85 | 0.08 | Univ Washington | 2012 | 67 | 0.09 |
| 8 | Canada | 2012 | 84 | 0.14 | Univ Calif San Francisco | 2012 | 66 | 0.07 |
| 9 | Netherlands | 2012 | 69 | 0.04 | Denver Hlth Med Ctr | 2012 | 57 | 0.02 |
| 10 | Brazil | 2012 | 64 | 0.02 | US Army | 2014 | 54 | 0.03 |