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An easy introduction to using these files is available.

A Basic FAQ and Technical FAQ are available.

The FAQs above make reading the Technical Documentation easier.

A collection of data sets of ICD9 titles is available.

NBER set up the processed versions of the files and combined the CM and PCS to make the files easier to use.


Clinical Modification (CM)
ICD-10-CM to ICD-9-CM SAS Stata CSV desc
ICD-9-CM to ICD-10-CM SAS Stata CSV desc
Procedure Coding System (PCS)
ICD-10-PCS to ICD-9-PCS SAS Stata CSV desc
ICD-9-PCS to ICD-10-PCS SAS Stata CSV desc
Combined CM and PCS
ICD-10-CM and PCS to ICD-9-CM SAS Stata CSV desc

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