For extracting ICD codes from OMOP CDM to calculate Elixhauser comorbidity scores
ohdsi_icd_elix
A data frame with 5 variables: concept_id, concept_name, vocabulary_id, concept_code, concept_code_strip
Elixhauser, A., Steiner, C., Harris, D. R. & Coffey, R. M. Comorbidity measures for use with administrative data. Med. Care 36, 8–27 (1998)
van Walraven C, Austin PC, Jennings A, Quan H and Forster AJ. A modification of the Elixhauser comorbidity measures into a point system for hospital death using administrative data. Medical Care 2009; 47(6):626-633. DOI: 10.1097/MLR.0b013e31819432e5