There are two related classifications of diseases with similar titles, and a third classification on functioning and disability.
The International Classification of Diseases (ICD) is the classification used to code and classify mortality data from death certificates.
The International Classification of Diseases, Clinical Modification is used to code and classify morbidity data from the inpatient and outpatient records, physician offices, and most National Center for Health Statistics (NCHS) surveys.
NCHS serves as the World Health Organization (WHO) Collaborating Center for the Family of International Classifications for North America and in this capacity is responsible for coordination of all official disease classification activities in the United States relating to the ICD and its use, interpretation, and periodic revision.
The Collaborating Center also is responsible in North America for the WHO Family of International Classifications, which includes the International Classification of Functioning, Disability and Health (ICF).