Number of articles reporting each source of funding support
| Funding source* | Number of articles |
| NIH Extramural | 10 377 |
| NIH Intramural | 594 |
| American Recovery & Reinvestment Act | 10 |
| US government Non-Public Health Services | 1922 |
| US government Public Health Services | 295 |
| Non-US government | 6746 |
*Funding sources defined: https://www.nlm.nih.gov/pubs/techbull/mj05/mj05_support_heading.html