(Not all versions of Dimensions have this categorisation system available for use)

The Research, Condition, and Disease Categorization (RCDC) System is a classification scheme used by the US National Institutes of Health (NIH) for public reporting required by the US Congress.

A RCDC Category can be a research area such as neuroscience, a disease such as diabetes, or a condition such as chronic pain. Some categories are very specific (such as ‘ataxia telangiectasia’) and some quite general (e.g. ‘neuroscience’). The 237 categories reflect the historical interest of the US Congress rather than a systematic and hierarchical approach to classification. Despite being a purely biomedical system, not all areas of biomedicine are covered, and some medical projects may not fall into any of the RCDC categories.

RCDC has been in use since 2008, and provides fairly consistent reporting, although the number of categories has increased from 215 to 237 in that time. The categories themselves have no verbal definitions, meaning that to understand them it is necessary to examine the terms used in their ‘fingerprint’ and their relative weightings and thresholds. Digital Science has taken the semantic definitions of RCDC categories and translated them to the Digital Science technology so that they are available within Dimensions. The NIH semantic definitions are a series of term searches connected by Boolean logic. The NIH modifies the semantic mapping of grants to categories using business and reporting rules (that is, rules that fall outside of the science itself). These business rules are highly specific to the NIH and have not been taken into account in our emulation.

RCDC reports for the US congress also utilize the specific aims section of the grant application. That is not available in Dimensions, which uses only the publicly available project title and abstract. This means we cannot emulate the published RCDC categories exactly, however our emulations provide a reasonable match, and can be applied to the title and summaries of publications and projects from funders which do not currently use RCDC.

NIH is the biggest funder in the world. By using RCDC, other funders will be able to compare themselves to NIH using a common terminology. Other funders will find that the bulk of disease and condition terms in RCDC are useful to them, but some terms are specific to North America (e.g. ‘American Indians/Alaska Natives’), and others may have different definitions (e.g. ‘underage drinking’).