ICD-10s and the WC System (Spotlight Report, published 09/15)

On October 1, 2015, the 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) became the standard classification system for all healthcare delivery in the United States, supplanting the outdated ICD-9 system. The transition to ICD-10 codes affects group health, federal programs (Medicare, Medicaid, Veterans Administration), as well as workers’ compensation. In the California workers’ compensation system alone, the changes in databases, data transfer protocols and business processes have affected medical service providers, medical bill payers, Utilization Review Organizations, Independent Medical Reviewers, Independent Medical Examiners/Qualified Medical Examiners, the state’s workers’ compensation reporting system, Medicare Set-Aside reporting and public policy research databases. This report reviews the history, the form and the function of the new classification system and outlines the similarities and significant differences in the ICD-9 and ICD-10 coding structures.