The table below displays the annual support level for various research, condition, and disease categories based on grants, contracts, and other funding mechanisms used across the National Institutes of Health (NIH) as well as disease burden data published by the National Center for Health Statistics (NCHS) at the Centers for Disease Control & Prevention (CDC).

At the request of Congress, the NIH embarked on a process to provide better consistency and transparency in the reporting of its funded research. This new process, implemented in 2008 through the Research, Condition, and Disease Categorization (RCDC) System, uses sophisticated text data mining (categorizing and clustering using words and multiword phrases) in conjunction with NIH-wide definitions used to match projects to categories. RCDC use of data mining improves consistency and eliminates the wide variability in defining the research categories reported. The definitions are a list of terms and concepts selected by NIH scientific experts to define a research category. The research category levels represent the NIH's best estimates based on the category definitions.

(Dollars in millions and rounded)
2015 2016 2017
Clinical Research $11,366 $11,867 $11,867
Genetics $7,480 $7,826 $7,879
Prevention $7,027 $7,300 $7,300
Biotechnology $6,018 $6,281 $6,281
Neuroscience $5,742 $6,041 $6,041
Cancer $5,389 $5,652 $6,332
Infectious Diseases $5,032 $5,249 $5,249
Women's Health $3,989 $4,140 $4,140
Brain Disorders $3,916 $4,108 $4,108
Behavioral and Social Science $3,762 $3,924 $3,924
Rare Diseases $3,679 $3,832 $3,832
Pediatric $3,632 $3,766 $3,766
Bioengineering $3,540 $3,697 $3,697
Clinical Trials and Supportive Activities $3,136 $3,266 $3,266
HIV/AIDS $3,000 $3,000 $3,000

8* Reporting for this category does not follow the standard RCDC process. This category assigns project funding according to populations tracked by gender or ethnicity. The databases used to track gender/ethnicity are complex are not currently compatible with the RCDC system.

9** The total for AIDS research includes both extramural and intramural research (including research management and support, Management Fund, and Service & Supply Fund), buildings and facilities, research training, and program evaluation, as well as research on the many HIV-associated co-infections and co-morbidities, including TB, hepatitis C, and HIV-associated cancers. It also includes all of the basic science underlying this research. Other RCDC categories are not reported this way; thus the total for AIDS-related research is not comparable to spending reported for other RCDC diseases. More information on this area is available at

17*** Name revised in FY 2015 from Clinical Trials.