Definition of Principal Diagnosis in the Official Guidelines

by Charlotte Lefert, RHIA

As all of you are aware, we continue to struggle with the definition of "principal diagnosis" for residents who remain in the nursing home. The Coding Team of the LTC Practice Council recently asked Sue Bowman, RHIA, CCS, AHIMA’s director of coding policy and compliance, for her opinion on whether the guidance in Coding Clinic Fourth Quarter 1999 related to “continued stay” in the nursing home could be added as a “note” in the official guidelines (Section II, Definition of Principal Diagnosis). In this 1999 Coding Clinic, the Cooperating Parties, in conjunction with the Editorial Advisory Board of Coding Clinic, indicated the following:

…The “first listed diagnosis” is the diagnosis that is chiefly responsible for the admission to, or continued residence in, the nursing facility and should be sequenced first. For example, when coding an admission to the facility, the “first listed diagnosis” is the condition chiefly responsible for the admission to the facility. If coding diagnoses during the resident’s stay, it is the condition chiefly responsible for the continued stay in the facility.

Bowman’s response indicated that the Coordination and Maintenance Committee does not address data set definition issues; it only addresses modifications to the ICD-9-CM coding system. The coding guidelines merely represent the definitions that are in the Uniform Hospital Discharge Data Set (UHDDS), which are part of the data standards for the data elements on the UB-04. As noted in the definition of principal diagnosis, this definition was published in the Federal Register in 1985. The use of this definition was extended to include all providers using the UB-04 billing form (or its electronic counterpart, the 4010) and expect these providers to use the UHDDS definition for reporting the principal diagnosis. Since the cooperating parties do not “define” data definitions, they are not able to include the expansion for “continued stay” in the regulatory definition. 

What Does This Mean for Us as HIM Professionals?  
Even though the “expanded” portion for “continued stay” is in the 1999 Coding Clinic guidance, the LTC Practice Council and LTC Community members must work to educate the industry on the guidance for determining the principal diagnosis in nursing homes—for both the initial admission and subsequent returns to facilities. Through use of AHIMA’s ICD-9-CM Diagnostic Coding for Long-Term Care and Home Care publication, the LTC CoP, the LTC Consortium Coding Modules (free on the American Health Care Association Web site), andthe LTC guidance in the 1999 Coding Clinic, it is essential that we continue to advocate for quality data for the LTC industry. 

American Hospital Association. Coding Clinic. Fourth Quarter 1999.

Article citation:
Lefert, Charlotte. "Definition of Principal Diagnosis in the Official Guidelines " Long Term Care Insights (August 2009).