Since 1979, the US had required ICD-9-CM codes for
Medicare and
Medicaid claims, and most of the rest of the medical industry in the US followed suit. On January 1, 1999, the ICD-10 (without clinical extensions) was adopted for reporting mortality, however, ICD-9-CM continued to be used for
morbidity. During that time, the U.S.
National Center for Health Statistics (NCHS) received permission from the WHO to create a clinical modification of the ICD-10. ICD-10-CM adapted ICD-10 in the following ways: • Allow the capture of information for ambulatory and managed care encounters • Expand available injury codes • Combine codes for diagnosis/symptoms to reduce the number of codes needed to describe a problem fully • Provide additional sixth and seventh digit classifications • Add classifications specific to laterality • Refine classification for increased data granularity == Adoption ==