Home Health ICD-9/ICD-10 Alert

Conquering Case Mix:

One Case Mix Diagnosis Remains Well Hidden

Dig deeply to get the reimbursement you earned.

Clarifying case mix diagnoses shouldn't be this hard, and hundreds of dollars hang in the balance.
 
More than a year after its appearance as a new ICD-9-CM diagnosis code, 331.82 is still confusing home health agencies. When the new codes debuted in October 2003, the coding manual directed coders looking for dementia with Parkinson's to 331.82 (Dementia with Lewy bodies), a newly created code.
 
But agencies became concerned about using that code because it was not listed as a case mix diagnosis in the Centers for Medicare & Medicaid Services' list. A case mix diagnosis gives the agency extra home health resource group points - leading to extra reimbursement - for a number of neurological, orthopedic and diabetic conditions specified in the final rule for the home health prospective payment system.
 
The case mix list was not updated to show any changes when the new codes appeared. And if you follow the instructions on the case mix list, you conclude that 331.82 is not included, explains coding consultant Lisa Selman-Holman with Denton, TX-based Selman-Holman & Associates.

Problem: This left coders in a quandary. Both dementia and Parkinson's disease are included in the list of case mix codes that add 20 points to the HHRG and at least $600 dollars to the episode reimbursement. If coders use 331.82 instead - as coding guidelines require - and it is not a case mix diagnosis, they lose out on that money, while still providing the more expensive care these conditions require, agencies say.

Good news: "We have checked and have confirmed that the grouper software accepts 331.82 as a case mix diagnosis," a CMS spokesperson tells Eli. Despite the fact that 331.82 is not included in the list of case mix diagnoses, it actually is one, the spokesperson confirms.

Use These Instructions To Code Correctly

Do not rely on the original list of case mix codes from the regulation, the spokesperson warns. Instead, you must search through the grouper updates on the CMS Web site. The current grouper version is 1.05 and, like each version, it contains text files showing the complete list of current case mix codes, the spokesperson says.
 
But don't expect the search to be simple. The grouper file is at
www.cms.hhs.gov/providers/hhapps/#Home. Open this link and then scroll down to "Prospective Payment System Coding and Billing" and click on the second bullet. This will let you unzip the file "PSEUO105.PDF file for the HHRG Grouper ZIP file:  HHRGO105.EXE 8/1/2003 Grouper Logic 'Pseudocode' Version: 01.05."
 
In the "Readme" file, the "Version Note" beginning at the bottom of page 8 and the one on page 11 refer to 331.82 as a new ICD-9 code being treated as a case mix diagnosis, the CMS spokesperson instructs. Unfortunately,  neither the table at the end of the Readme file nor the lists in the pseudocode shows 331.82, he admits.