The Medical and Research Definitions resource defines codes for diagnoses, procedures and tests commonly analyzed at MCHP, along with any necessary programming notes and key references.

The codes include those from classification systems such as ICD-9-CM, from physician tariff codes, and from common groupers such as the Diagnosis Related Grouper (DRG), Refined Diagnosis Related Grouper (RDRG), and the Case Mix Grouper (CMG).

Both researchers and programmers/analysts consult this resource to find out what definitions others have used, and to determine whether they are appropriate for their studies.