minimal Common Oncology Data Elements (mCODE) Implementation Guide
2.1.0 - STU 2.1 United States of America flag

This page is part of the HL7 FHIR Implementation Guide: minimal Common Oncology Data Elements (mCODE) Release 1 - US Realm | STU1 (v2.1.0: STU 2) based on FHIR R4. This is the current published version. For a full list of available versions, see the Directory of published versions


The mCODE Assessment group contains information related to the patient’s general health, before and during treatment.


Comorbidities are important in the prognosis and treatment of cancer. Comorbid conditions in mCODE are aligned with the Elixhauser Comorbidity Index. A similar approach could be used with other systems of comorbidity assessment, such as the Charlson Comorbidity Index, but that remains outside the scope of mCODE.

Performance Assessments

mCODE supports the Eastern Cooperative Oncology Group (ECOG) Performance Status and Karnofsky Performance Status (KPS). Because performance assessments may be performed more than once over a period of time, multiple instances may exist for a single patient.

Laboratory Tests

Many laboratory tests could be relevant to an individual with cancer. mCODE includes results from two common laboratory panels, the Complete Blood Count (CBC) (Automatic or Manual Differential) and Comprehensive Metabolic Panel (CMP). In practice, there are many variations on these panels, as exemplified by this list of various CBCs. The individual LOINC codes of interest to mCODE are broadly any that may be part of various CBC and CMP panels.

CBC and CMP results can be reported as individual laboratory observations or as panels, using the DiagnosticReport resource. Individual laboratory results must conform to the US Core Laboratory Result Profile. Several examples of laboratory result reporting are given in the US Core IG. For example, see this erythrocytes laboratory reporting example.

If DiagnosticReports are submitted, they must conform to US Core DiagnosticReport Profile for Laboratory Results Reporting. Examples of CBC reporting and CMP reporting are given in the US Core IG.

Beyond the requirements of US Core, under Clinical Laboratory Improvement Amendments (CLIA) regulations, laboratory tests must include information on the performing technologist, performing laboratory, and performing laboratory medical director. These three roles would ideally appear as slices on Observation.performer and/or DiagnosticReport.performer. However, slicing requires a discriminator, a field that can be checked to determine whether a resource found in Observation.performer or DiagnosticReport.performer corresponds to the performing technologist or the performing laboratory medical director. While the performing laboratory can be determined by its resource type, in the current design of FHIR, there is no indicator that would discriminate the roles of the two Practitioner participants.

Vital Signs

Vital signs are measurements of the most essential, or “vital” body functions. For mCODE, blood pressure, body height, and body weight are believed to be most critical to assessment and treatment. Instead of defining its own profiles, mCODE uses the FHIR R4 vital sign profile, which is incorporated into US Core. As of Version 3.2, US Core defines its own set of vital signs profiles. These profiles are derived from the same FHIR base vital sign profile. mCODE accepts vital sign data conforming to either FHIR or US Core profiles. Examples of height, weight, and blood pressure are given in both sources.



Value Sets