Selecting (and defending) the primary diagnosis

In Blog, ICD-10 by Lisa Selman-HolmanLeave a Comment

Getting the right primary diagnosis can be a real challenge, and generate some lively debate among clinicians, QA managers and coders. Ultimately, we must meet the requirements for payment under the Medicare coverage and payment regulations.

The primary diagnosis must be supported by documentation in three places
  • The Face-to-Face encounter note from the physician or non-physician provider
  • The problem(s) identified on the comprehensive assessment
  • The interventions and goals on the Plan of Care.
Steps in determining the primary diagnosis at the Start of Care
  1. The assessing clinician completes the comprehensive assessment and reviews all referral information, including the F2F documentation, to identify the needs of the patient.
  2. Any diagnoses identified on assessment and not documented in the referral information must be verified with the physician or approved non-physician provider before listing on the POC.
  3. Based on the assessment, what is the focus of home care services? If therapy and nursing are both involved in the case, it’s best to coordinate between disciplines when identifying the focus of care.  What is the focus of care based on patient’s needs and the services the agency will provide?
  4. Check the F2F encounter for the reason for the referral to home care services. Does it reflect the patient’s needs identified on the comprehensive assessment?
  5. Is the focus of care identified by the clinician(s) assessment the same as the F2F reason for referral to home care?
    • If not, is the focus of care diagnosis documented in the F2F encounter note?  If it isn’t mentioned at all in the F2F encounter documentation, you may need a new F2F encounter to change the primary diagnosis to the focus of care identified by assessment.
  1. Is this focus of care an acceptable primary diagnosis in PDGM?
    • If not, can you choose a different primary diagnosis or identify the underlying cause for the diagnosis/condition? This will usually require a query to the physician, and may require a new F2F encounter. Document all communication with the certifying physician or non-physician provider regarding verification of diagnoses and confirmation of the focus of care (primary diagnosis).
  1. Does the POC have interventions and goals related to the primary diagnosis?
  2. Sequence the secondary diagnoses according to their importance to the Plan of Care.
  3. Coders: apply the coding conventions and guidelines to the sequencing of diagnoses.  It may be necessary to change the listing order of diagnoses to comply with coding conventions.  For example: if the patient has a primary diagnosis of CHF and also has HTN, the code for hypertensive heart disease must be listed before the heart failure code.

Click to view part 1 and part 2 on Meeting the F2F Challenge.

Determining the primary diagnosis for the second 30-day payment period

The primary diagnosis for each 30-day payment period must be determined, and the diagnosis codes must be updated to reflect the actual care to be delivered for that 30 days. If the patient’s primary diagnosis from the Start of Care has been resolved, that diagnosis should be removed from the POC. A mini-case conference is a great idea at day 28-30 to determine if the focus of care has changed, or you may use a 30-day update tool to communicate any changes to the coder and biller prior to submitting the RAP for the second 30-day payment period.  Changes in diagnoses might include any new diagnosis, any exacerbation of a diagnosis, the resolution of a diagnosis, or a medication change (impacts use of Z79.- codes).

Consider this example

The patient is admitted to home care with a primary diagnosis of a UTI, on antibiotic treatment and nursing is assessing response to treatment and teaching medications, s/sx to report and prevention of further UTIs.  The patient has a fall one week later, PT evaluates and begins fall prevention and gait training interventions.  At the end of the first 30 days, the UTI is resolved, nursing has completed all necessary education, and only therapy is continuing their plan of care orders into the next 30 days.  It would not be appropriate to continue to code the UTI as the primary diagnosis for this patient since the UTI is resolved and the patient has no further urinary problems on assessment, there are no orders on the plan of care for antibiotics or other treatment, and it is not the focus of care for the upcoming 30-day payment period.


Teresa Northcutt, BSN, RN, HCS-D, COS-C, HCS-H
Senior Associate Consultant | Selman-Holman, a Briggs Healthcare

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