Developing and Evaluating Mappings of ICD-10 and ICD-10-CM Codes to Phecodes
The phecode system was built upon the ICD-9-CM for PheWAS using the EHR. In this study, we developed and performed an initial evaluation of maps from ICD-10 and the ICD-10-CM codes to phecodes. We mapped ICD-10 and ICD-10-CM codes to phecodes using a number of methods and resources, such as concept relationships and explicit mappings from the Centers for Medicare & Medicaid Services, the UMLS, OHDSI, SNOMED-CT, and the NLM. We assessed the coverage of the maps at VUMC and UK Biobank. We also assessed the fidelity of the ICD-10-CM map in comparison to the gold-standard ICD-9-CM phecode map by investigating phenotype reproducibility and conducting PheWAS. These initial phecode maps allow researchers to leverage accumulated ICD-10 and ICD-10-CM data for PheWAS in the EHR.