IRF Grouper - Case Mix Group (CMG)
This new version applies to Federal Fiscal Year (FFY) 2020. It uses the Quality Indicator items, incorporates an unweighted motor score calculation, contains revised case-mix groups, and updates the ICD-10-CM codes used by the CMG grouper. NOTE: During the beta testing, there were errors in the DLL for low motor score values documented in Appendix E. These errors were corrected for the final release.
This new version applies to Federal Fiscal Year (FFY) 2019. This new version incorporates revisions to the list of comorbidities used by the CMG grouper.
This new version incorporates revisions to the comorbidities used by the CMG grouper.
This new version incorporates revisions to the list of comorbidities used by the CMG grouper.
This new version incorporates a correction to the handling of comorbidities by the CMG grouper.
The test data files posted with the original CMG 2.81 package are flawed. Only two of the four test files were included and the test records in the two posted files had CMG Version number of 2.80 instead of the correct value of 2.81. The current posting contains the correct four test data files. The two test data files in the original package should be discarded and the present four files should be used for CMG 2.81 testing.
CMG Version 2.81 [ZIP, 2.05mb] (ZIP):
Version 2.81 of CMG is now available. Version 2.81 replaces Version 2.80 and corrects a very rare error in Version 2.80. The rare error in Version 2.80 involves comorbidity Tier assignment based on the comorbidity diagnosis codes on the IRF-PAI assessment. Comorbidity Tier assignment is made on the basis of the presence of specific single ICD-10-CM diagnosis codes and on the basis of specific ICD-10-CM code combinations. The same code can be a qualifying single code and also a member of a code combination. When a code combination is present on the assessment and excluded because of the assessment’s Rehabilitation Impairment group (RIC), then a code in the combination, which is also considered as a single code, must also be excluded. The error in Version 2.80 is that it does not exclude single codes included in an excluded combination. This error has been corrected in Version 2.81.
The final version of CMG 2.80 is now available. CMG 2.80 will be effective for IRF-PAI assessments with discharge date on or after October 1, 2015. The major change with CMG 2.80, from the current version CMG 2.70, is to use ICD-10 diagnosis codes for the comorbidities (Item 24 on the IRF-PAI) rather than ICD-9 codes. The comorbidity ICD-10 codes used have been determined with the CMS General Equivalence Mapping (GEM) for converting ICD-9 codes to ICD-10 codes. There are no changes to the CMG logic for determining RIC and CMG group number.
The final version of CMG 2.70 is now available. The only changes with the final version of CMG 2.70 (from the previous draft version) is to remove the word “Draft” from the file names and documentation headers of “Technical documentation.pdf” and Program documentation.pdf”. There are no other changes to the documentation and no changes to the software and test data. CMG 2.70 will be effective for IRF-PAI assessments with discharge date on or after October 1, 2014. The major change with draft version of CMG 2.70, from the current version CMG 2.60, is to accommodate the expansion of the comorbidities (Item 24 on the IRF-PAI) from a maximum of 10 ICD-9 codes to a maximum of 25 ICD-9 codes. There are no changes to the CMG logic for determining RIC, CMG group number, and comorbidity tier.
CMG V2.70 Corrected XML Test Data [ZIP, 1.455mb]: In the XML test data included with the CMG 2.70 package, an incorrect format has been used for Item 24 comorbidities that are skipped. The data specifications require a skipped comorbidity to be coded as a single caret [^] but the test data has been coded as a caret with trailing blanks [^ ]. There are additional problems with records 139 and 140, with Item 23 (date of onset of impairment) being before Item 6 (birthdate). These errors have been corrected in a new XML test data file (CM1F15V9 xml.zip) now available for download.
CMG V2.70 Errata [PDF, 35.7kb]: An updated Errata document for CMG V2.70 (dated 12/9/2014) is now available. The update adds a third item explaining XML test data problems and the corrections made.
The following updates are available for download from the IRF-PAI Data Specifications-archive file in the Downloads section below:
- IRF-PAI Data Specifications October 1, 2010
- IRF-PAI Data Specifications October 1, 2009
The following updates are available for download from the CMG Grouper-archive file in the Downloads section below:
- CMG Grouper (Version 2.50) October 1, 2010
- CMG Grouper (Version 2.40) October 1, 2009
- CMG Grouper (Version 2.30) October 1, 2008