Comparability of Cause-of-death Between ICD Revisions

Cause-of-death titles change from time-to-time. This reflects the periodic revisions to the classification (the International Classification of Diseases (ICD-10, ICD-9, and earlier revisions) used to show cause of death. The classification is revised to incorporate and capture changes in medical knowledge. The revisions, in some instances, do create breaks in the comparability of a cause of death between two years.

Studies of the comparability between revisions of the ICD are routinely done as part of the implementation of a new revision of an ICD. The Hetzel (1997) publication [PDF - 591 KB] lists comparability study reports that should be examined in connection with trend analyses that cross ICD revisions. The key measure in a comparability study is a comparability ratio that represents the net effect of the new revision on cause-of-death statistics.

Source documents for the tables shown include unpublished worktables from CDC/National Center for Health Statistics, National Vital Statistics System, Mortality data and CDC/NCHS publications.

Reports on the comparability of cause-of-death classification between:

• ICD-9 and ICD-10 [PDF - 337 KB]
  • Mechanism of Injury and Intent of Death (Table I) [PDF - 4.7 MB]
• ICDA-8 and ICD-9 [PDF - 1.9 MB]
• ICD-7 and ICDA-8
  • Final [PDF - 6.4 MB]
  • Provisional [PDF - 1 MB]
• ICD-6 and ICD-7 [PDF - 5.5 MB]
• ICD-5 and ICD-6 [PDF - 5 MB]
• ICD-4 and ICD-5
  • Comparability [PDF - 24 MB]
  • Comparability of titles through five revisions [PDF - 510 KB]
• Comparability across revisions for selected causes table [PDF - 33 KB]

Downloadable data sets for ICD-9/ICD-10 study:

• Readme file
• Comparability data set documentation
• 1996 data set documentation [PDF - 16 MB]
• Comparability data set
• Comparability ratio tables
• SAS Input Statements
• A Guide to State Implementation of ICD-10 for Mortality, Part II: Applying Comparability Ratios (51 pages) [PDF - 374 KB]