International Classification of Diseases (ICD)

Used to code and classify cause-of-death data. ICD is developed collaboratively by the World Health Organization and 10 international centers, one of which is housed at the National Center for Health Statistics (NCHS). ICD promotes international comparability in the collection, classification, processing, and presentation of health statistics. Since 1900, ICD has been modified about once every 10 years, except for the 20-year interval between the 9th and 10th revisions (ICD–9 and ICD–10) (ICD-Table). The purpose of the revisions is to stay current with advances in medical science. New revisions usually introduce major disruptions in the time series of mortality statistics. The most recent revision, ICD–11, was adopted by the World Health Assembly in 2019 and became effective internationally on January 1, 2022, although the United States continues to use ICD–10 for mortality coding (see Sources and Definitions, Cause of death). For more information, see the NCHS ICD–10 website. (Also see Sources and Definitions, Cause of death; Comparability ratio; International Classification of Diseases, Clinical Modification [ICD–CM].)

ICD-Table. International Classification of Diseases, by year of adoption and years in use in United States

SOURCE: National Center for Health Statistics. Classification of Diseases, Functioning, and Disability.