<< Previous Data Element X12-837 Input Table of Contents Next Data Element >>
Data Element Name:  Principal/Primary Diagnosis Code
Format-Length:  A/N - 6 Required For:  AS, ED, IP
Effective Date:  1/1/94 Revision Date:  September 2003

NOTE: This data element is a SPARCS extension, for mapping guidelines refer to the Inpatient and Outpatient 837 Addenda.
National Standard Mapping:

Electronic - 837I
X12 Loop
Ref. Des.
Data Element
Code
Description
Version 4050R 2300 HI01-1 1270 BK Principal Diagnosis Qualifier
HI01-2 1271 Principal Diagnosis Code
Paper Form Locator Code Qualifier
Institutional - UB-04 67 N/A

Definition:

The Principal/Primary Diagnosis is the condition established after study to be chiefly responsible for occasioning the admission of the patient to the hospital for care. Since the Principal/Primary Diagnosis represents the reason for the patient's stay, it may not necessarily be the diagnosis which represents the greatest length of stay, the greatest consumption of hospital resources, or the most life-threatening condition. Since the Principal/Primary Diagnosis reflects clinical findings discovered during the patient's stay, it may differ from Admitting Diagnosis.

In the case of admission to the hospital-based ambulatory surgery service or freestanding ambulatory surgery center, the Principal/Primary Diagnosis is that diagnosis established to be chiefly responsible for occasioning the admission to the service or center for the specific procedure.

In the case of emergency department visits, the Principal/Primary Diagnosis Code is that diagnosis established to be chiefly responsible for occasioning the visit to the Emergency Department.

Codes and Values:

  1. Must be a valid ICD-9-CM code. To be valid, ICD-9-CM codes must be entered at the most specific level to which they are classified in the ICD-9-CM Tabular List. Three-digit codes further divided at the four-digit level must be entered using all four digits. Four-digit codes further subclassified at the five-digit level must be entered using all five digits. Failure to enter all required digits in the diagnosis codes will cause the record to be rejected.

  2. Must be entered exactly as shown in the ICD-9-CM coding reference.

  3. Inpatient Only:
    a. Manifestation and Unacceptable Principal/Primary Diagnosis conditions as indicated by the edit flag on the ICD-9-CM reference file are invalid.

    b. E-codes are not valid as Principal/Primary Diagnosis Codes. E-codes are reported in External Cause-of-Injury Code and Place-of-Injury Code.

  4. Outpatient Only:
    E-codes are not valid entries.

Example: HI*BK:63491*BJ:63491~

Edit Applications:

  1. Edits pertaining to ICD-9-CM codes are validated on the basis of the Statement-Covers-Thru Date and Expected Principal Reimbursement depending on conditions described in Appendix N, which include age-specific and sex-specific diagnosis code conditions.

  2. Diagnosis codes reported in the range of 800.00-999.99 require the reporting of a valid External Cause-of-Injury Code unless listed as an exception in Appendix N.

  3. Inpatient and Emergency Department Only:
    If the Principal/Primary Diagnosis is reported as Acute Myocardial Infarction (AMI) 410.0x - 410.9x, then Heart Rate on Arrival, Systolic Blood Pressure on Arrival and Diastolic Blood Pressure on Arrival must be reported.

  4. Inpatient Only:
    a. If the Principal/Primary Diagnosis is reported as Newborn the Neonate Birth Weight and Mother's Medical Record Number for Newborn Child must be reported. When the Neonate Birth Weight is reported as less than 1500 grams, and the New York State Patient Status is reported as code "01" home, then the Length of Stay must be greater than 10 days.

    b. When the edit flag on the ICD-9-CM reference file indicates an "unacceptable principal diagnosis without a secondary diagnosis" an Other Diagnosis Code 1 must be reported.
<< Previous Data Element X12-837 Input Table of Contents Next Data Element >>