Frequently Asked Questions about the NIH Research, Condition, and Disease Categorization (RCDC) System


1. What is RCDC?

RCDC (Research, Condition, and Disease Categorization) is a computerized reporting process the National Institutes of Health (NIH) uses at the end of each fiscal year to categorize its funding in medical research beginning with fiscal year 2008 (FY 2008) RCDC reports NIH funding in more than 280 research, condition, and disease categories. 

RCDC reports on three types of NIH funding:

  • Research grants (extramural research)
  • Research and development (R&D) contracts
  • Research conducted in NIH’s own laboratories and clinics (intramural research)

A category can include a:

  • Research area such as neuroscience,
  • Disease such as asthma, or
  • Condition such as chronic pain.

2. What are the categories?

To see a list of categories the NIH currently reports on its website, please go to Categorical Spending Page

3. What is a RCDC project listing?

The RCDC process produces a complete list of the funded projects included within a category.

This list is known as the “project listing.” Here is an example:

RCDC Category: Disease “Z”

Project Listing for Disease “Z”:

  • Project 1
  • Project 2
  • Project 3
  • Project 4

Projects can be research grants, contracts, or intramural research (research conducted in the NIH’s own laboratories and clinics). Projects can fall into one or more categories because scientific research has multiple components that characterize its scientific content, methods, and aims.

4. Are there categories that do not follow the standard RCDC categorization process?

Yes. There are nine categories that do not follow the standard RCDC process for a variety of reasons.

Specific budget classification policies required the NIH to take a nonstandard approach to the following five categories:

  • Biodefense
  • Pediatric AIDS
  • Vaccine Related (AIDS)
  • Drug Abuse

All National Institute on Drug Abuse (NIDA) spending, and only NIDA spending, is reported for the category of Drug Abuse, which is consistent with the requirements of the U.S. Office of National Drug Control Policy.

Significant technical challenges required the NIH to take a nonstandard approach to the following three categories:

  • Women's Health
  • Minority Health
  • Health Disparities

These three categories assign project funding according to populations tracked by gender or ethnicity. The databases used to track gender and ethnicity are complex and not yet compatible with the RCDC system.

  • Human Fetal Tissue

The Human Fetal Tissue category also uses a nonstandard approach because the required information for proper categorization (tissue type) is usually not stated in the project summary.

5. How was the RCDC process developed?

RCDC is a complex process that helps categorize ongoing NIH-supported research throughout the country. Hundreds of NIH technical and scientific experts helped to create the RCDC methods and identify key terms and concepts. This input from NIH staff laid the groundwork for the computerized RCDC process to develop definitions for categorizing NIH-supported research. The definitions are not given in sentences. Instead they take the form of a list of scientific terms and concepts. In order to successfully categorize NIH¹s research portfolio based on biomedical and scientific concepts, the thesaurus is curated to add or remove concepts and synonyms based on scientific need. The process takes into consideration how the automated system operates. A full list of the terms used in this process is available in the RCDC thesaurus.

Two offices within the NIH Office of the Director guided the process:

  • The Division of Program Coordination, Planning, and Strategic Initiatives (DPCPSI) managed and coordinated the project.
  • The Electronic Research Administration in the Office of Extramural Research created the RCDC process with support from the Center for Information Technology.

Other offices within the Office of the Director also have participated in the project. All NIH Institutes and Centers have been actively engaged in nearly every facet of the process from establishing new NIH policies to creating the category definitions.

6. Why did the NIH develop RCDC?

The NIH is the Nation's medical research agency.
The NIH, funded by U.S. tax dollars, supports biomedical research across the country and around the world. The American people want to know how the NIH spends their tax dollars. The RCDC process categorizes the NIH research projects funded with these tax dollars.

The NIH needed a more consistent, modern system.
With advances in data- and text-mining computer technology, the NIH recognized that it could transform its process for developing spending reports. In 2004, the NIH tested the small-scale application of a new computerized process that demonstrated the potential to accurately sort NIH-funded research projects into categories. This initial analysis led to the development of the full-scale RCDC process.

Congress issued a mandate.
In 1998 and 2003, the National Academy of Sciences, an independent organization, issued two reports recommending this type of change. The U.S. Congress also understood the value and importance of a more consistent and transparent system to describe how the NIH categorizes its research at the end of each fiscal year. As a result, in 2006, Congress added a requirement in the NIH Reform Act to build a tool to categorize the agency's research.

7. Did RCDC change the way the NIH funds research?

No. The NIH receives its budget from Congress at the beginning of each fiscal year. The NIH funds the most meritorious investigator-initiated scientific research proposals it receives using a two-level peer review process. At the end of each fiscal year, the NIH reports how much it spent in more than 280 categories (many of which Congress identified for reporting). This reporting process will continue, and the way the NIH funds research will remain the same.

8. Did RCDC change the way researchers apply for grants?

No. RCDC had no impact on the grant application and review process.

9. Where can the public see the RCDC reports?

The NIH website RePORT (the Research Portfolio Online Reporting Tools).gives the public a single access point to quickly and easily find a variety of NIH-related data. The RCDC results tables are one of several new and evolving features on the RePORT site. The public can view, print, and download the RCDC results from the RePORT website.

10. What do the reports look like?

The public website for RCDC reports is very similar to the current NIH category-reporting website at Categorical Spending Page Most importantly, the new website, for the first time, provides project listings and associated dollar amounts. The project listings and summary data can be downloaded.

11. How is the RCDC process different from previous NIH reporting systems or methods?

The RCDC process is different in two important ways.

First: RCDC applies a consistent categorization process for each research area, disease, or condition and provides a uniform report for all of the NIH.

The NIH comprises 27 Institutes and Centers (ICs), each with its own mission and budget. Until now, each IC sorted and categorized its own funding based on its own mission. Reports were not always produced using the same definitions across the NIH, even though many ICs do research in related areas. The RCDC process uses the same category definitions universally and applies them uniformly to all types of research at all of the ICs.

Second: The public can access the detailed reports on the Internet.

RCDC category summary results are available on a public website. RCDC also produces more detailed funding reports so that the public can see a complete list of projects by title in each category and the associated dollars spent.

12. What are the benefits of the RCDC process?

RCDC offers the public, scientists, and the NIH staff a quick and easy way to get a complete list of research projects funded in more than 280 specific research areas, diseases, or conditions.

RCDC is consistent.
RCDC produces standard, reliable reports across all ICs. The sorting process is consistent and reproducible. All ICs use the same NIH-wide category definition for a research area, disease, or condition. For reporting purposes, all ICs use the same terms, process, and project listing to describe the same disease or condition.

RCDC is detailed.
RCDC reports provide the following detailed information for each category with estimates for the next two years posted on the public RePORT website:

  • A total dollar amount for a category
  • A project listing—All projects whose summaries meet the category standard
  • Project-specific information that can be sorted by:

13. How were the RCDC research area, disease, and condition categories chosen?

The more than 280 categories include those that were, over time, requested by Congress and other Federal agencies for reporting to Congress and the public.

14. How are the categories organized?

RCDC lists categories alphabetically.

15. What if a research area, disease, or condition is not included among the list of categories?

The categories included in RCDC are those that the NIH has historically reported to Congress and the public. New categories are considered annually to accommodate requests from Congress and the public. Existing categories will continue to be refined periodically to reflect scientific advances.

16. Can the categories be modified if a project is assigned to the wrong category?

RCDC uses a text-mining computer application to assign NIH-funded grants and contracts to categories. Before the RCDC process, ICs applied scientific judgment to assign projects to categories based on the ICs' research missions. The RCDC process might produce different categorization results because the computerized process relies solely on the clarity and specificity of the text provided and uses new trans-NIH definitions. For these reasons, in viewing the RCDC project listings, researchers might agree or disagree with the categories in which their projects appear. The NIH took a range of precautions to check each category for obvious errors before posting the first RCDC reports. New category assignments do not reflect changes in research priorities or IC missions.

17. Are basic research projects included in the RCDC project listings?

Yes. Basic research is included in a RCDC project listing when it is directly and closely related to that category. Basic research examines scientific questions to expand knowledge and understanding and is fundamental to the NIH and the research enterprise. Because of its fundamental nature, basic research often can have a direct impact on many different research areas and diseases. The wide applicability of some basic research can make it difficult to categorize. For example, basic research on the blood-brain barrier affects research related to drug delivery, cancer treatment, infections, and more. But such research projects might not fall into every category that includes treatments developed using knowledge about the blood-brain barrier. 

18. Do the numbers in RCDC reports add up to the total NIH budget?

No. All of the categories added together will not equal the total NIH appropriation for the following reasons:

  • Research projects are often applicable to more than one RCDC category.
  • RCDC categories are by their nature overlapping (for example, Brain Disorders, Neurosciences, and Mental Health).
  • RCDC categories do not encompass all types of biomedical research.

As a result, some NIH-funded projects might fall into several of the more than 280 reported categories, whereas other projects will not be categorized at all.

19. Does each category stand alone?

Yes. Each category stands alone. RCDC approaches each research category as a separate inquiry, answered to the best of its ability. RCDC answers two questions for each category:

  • What is the scope of research (as demonstrated by the project listing)?
  • What was spent (the dollar amount) in this category?

RCDC does not prorate (divide proportionately) costs of projects in a category. RCDC counts all projects at 100 percent of their funded levels in all of the categories in which they appear. Though each category stands alone, one research project might be related to more than one RCDC category. For example, an imaginary project whose title is "Depression in older men with diabetes" could be sorted into four categories:

  • Depression
  • Aging
  • Mental Health
  • Diabetes

Excluding this project from any one of these four categories would result in an incomplete and inaccurate listing of projects associated with that category. The NIH developed RCDC to be as accurate, comprehensive, and detailed as possible for each individual category. Within RCDC, there is no accurate and uniform way to appropriately divide the relevant costs associated with one research project.

In some cases an entire category’s project listing can be contained within another category, for example Breast Cancer and other cancer related categories are part of the project listing for the Cancer.

RCDC is not intended to account for the entire NIH budget across thousands of research topics.

20. Why might the numbers in the RCDC report change from the numbers NIH reported in previous years?

The RCDC process changed entirely the method the NIH used to report its funding by category to Congress and the public. Beginning with FY2008, categories were produced via the RCDC computerized system. Using this new system created differences for some categories, but with the new process it allowed the NIH the ability to show the public the project lists for the categories.

21. How will RCDC change in the future?

The NIH anticipates three types of changes to the RCDC process in future years:

  • The NIH will update category definitions as science advances.
  • The NIH will improve the RCDC process as computer technology improves.
  • The projects included in a category (that is the project listing) will change as new research is funded.

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