Code Map Services

The Code Map Services project was in part funded through Office of the Assistant Secretary for Planning and Evaluation (ASPE) for the Patient-Centered Outcomes Research Trust (PCORTF). This project is phase III of the Common Data Model Harmonization (CDMH) project. Through the use of common data models (CDMs), scientists conduct analysis of real-world data which is critical for healthcare and clinical research. CDMs standardize the structure, format, and terminologies for data, so researchers can collaborate, share data, and conduct analyses across different datasets. Code Map Services provide researchers with an automated tool to transform (machine to machine) data collected and stored among CDMs and/or data standards:

• The National Patient-Centered Clinical Research Network (PCORnet)
• The Observational Medical Outcomes Partnership (OMOP)
• FDA Sentinel Initiative
• Health Level Seven International (HL7) Fast Health Interoperability Resources (FHIR) US Core Profiles V6 (based on United States Core Data for Interoperability USCDI)
• Informatics for Integrating Biology & Bedside / Accrual to Clinical Trials (i2b2/ACT)
• TriNetX
• Clinical Data Interchange Consortium (CDISC) Study Data Tabulation Model (SDTM)

Code Map Services establish a source of truth within the Cancer Data Standards Registry and Repository (caDSR, a shared metadata mapping repository) by using standards-based semantic annotations for establishing model-to-model equivalents. Mappings can evolve and be versioned over time, thereby improving and expanding functionality with each release.

This project will harmonize semantics across multiple CDMs and data standards to provide researchers in federal agencies and academia with access to real-world data from various data sources (such as electronic health records and administrative claims) and from different research networks. The data elements in these models will be registered in caDSR as Common Data Elements (CDEs).

Code Map Services advance the ability to conduct high-quality and efficient patient-centered outcomes research and other types of research studies. Along with publicly available transformation rules, caDSR will enable Transformation tool vendors to provide services to the CDM communities to extend the accessibility of their data to other communities, vastly expanding the impact of their work.

The caDSR II features support a collaborative effort:

Model owners can:

• Register models, as described in Registering a Model as a Model Owner. 
• Maintain models and model versions, as described in TBD.
• Register CDEs for new models, as described in TBD.

Model experts can:

• Create model mappings, as described in Mapping Models as an Expert. 
  • Maintain model mappings, as described in TBD.
  • Support blocks of pseudocode and generate pseudocode, as described in TBD. 
  • Generate semantic mapping rules (transformation rules) between two models, such as semantically equivalent and semantically similar, as described in Generating a Semantic Map and a Value Map. 
  • Review and manually create rules where fields are not semantically aligned, as described in Reviewing and Updating Transformation Rules. 
  • Generate value mappings based on the CDEs, as described in TBD, including value mappings for data coded using local codes. 
  • Review and manually adjust values not mapped, as described in TBD. 
• Support reviews and record provenance, as described in TBD.

• Generate code to be used by an ETL (extract, transform, load) tool and use a pre-parser to customize generated code. 

ETL programmers can implement the rules themselves or use generated code:

• Value mapping tables for enumerated variables
• Limited NCI Metathesaurus / NCI Thesaurus terminology cross-walk mapping tables for data coded using a subset of selected standard terminologies
• Rules retrieved via:
  • OneData graphical user interface for review and export/download
  • Application Programming Interfaces (APIs) and a File Transfer Protocol (FTP) site for retrieving model information and mappings

If you have questions, refer to the caDSR II Metadata Management Knowledge Base:

• Home page: https://service.cancer.gov/cadsr-curation?id=nci_ext_kb_homepage
• Curation Glossary: https://service.cancer.gov/cadsr-curation?id=nci_ext_kb_article&sysparm_article=NCI-KB0015054
• caDSR II and ISO 11179: https://service.cancer.gov/cadsr-curation?id=nci_ext_kb_article&sys_kb_id=a04edf101b5f9910932da8efe54bcb96