Principal Diagnosis - Inpatient

Principal Diagnosis

Often, instructions in the code book, or other official guideline, provide sequencing direction even though multiple conditions may meet the definition of Principal Diagnosis.

Be mindful of:

1.       Uniform Hospital Discharge Data Set (UHDDS) definition

2.       Chapter-Specific guidelines

3.       Uncertain Diagnoses

4.       Two or more diagnoses

Selection of Principal Diagnosis

The circumstances of inpatient admission always govern the selection of principal diagnosis.

The principal diagnosis is defined in the Uniform Hospital Discharge Data Set (UHDDS) as “that condition established after study to be chiefly responsible for occasioning the admission of the patient to the hospital for care.”

Principal Diagnosis: Uncertain Diagnosis

Official Guideline: If the [principal] diagnosis documented at the time of discharge is qualified as ‘probable’, ‘suspected’, ‘likely’, ‘questionable’, ‘possible’, ‘still to be ruled out’, or other similar terms indicating uncertainty, code the condition as if it existed or was established.

Remember to distinguish between ‘Rule out’ diagnoses versus ‘Ruled out’ diagnoses

Principal Diagnosis: Two or More Diagnoses

Official Guideline: In the unusual instance when two or more diagnoses equally meet the criteria for principal diagnosis, as determined by the circumstances of admission, diagnostic workup, and/or therapy provided, and the Alphabetic Index, Tabular List, or another coding guidelines does not provide sequencing direction, any one of the diagnoses may be sequenced first.

This rule now applies to a symptom followed by two or more comparative or contrasting diagnoses. Code the comparative/contrasting diagnoses, do NOT code the symptom.

A symptom(s) followed by contrasting/comparative diagnoses

GUIDELINE HAS BEEN DELETED EFFECTIVE OCTOBER 1, 2014

The Official Guideline for two conditions as Principal Diagnosis is much more strictly defined than both conditions merely being present at the time of admission.

It is always inappropriate to base coding decisions solely on reimbursement or public reporting implications.