Inventory of Health Care Information Standards. HCFA National Standard Format (NSF), Version 002.00


Contact for More Information:

Joy Glass - Email, 410-786-6125, FAX 410-786-4047

Description of Standard:

The NSF consists of fixed-length (320 bytes) records. Each record has a unique identifier and logically related data elements.

A) Objective - The NSF was designed to standardize and increase the submission of electronic claims and coordination of benefits exchange.

B) Function - The NSF is used to electronically submit health care claims and encounter information from providers of health care services to payers. It is also used to exchange health are claims and payment information between payers with different payment responsibility.

C) User Environment - NSF users consist of a variety of health care providers, such as, professional, dental, chiropractic, Indian health service providers, and suppliers of medical equipment and supplies. A variety of payers also use the format to exchange claim and payment information.

D) Systems Environment - The NSF is a file format and is platform/operating system independent.

E) Application Function/Domain Completeness - All codes used in the NSF are complete.

A) The NSF is "user friendly" and easily implemented. It contains detailed record and data descriptions as well as unambiguous data definitions. It is widely used by providers of health care and payers. In FY96, 668,650,936 Medicare claims were submitted electronically. Ninety eight (98) percent of those claims were in the NSF. The NSF does not have to be translated prior to application processing. The use of compression techniques eliminates at least 50% overhead when transmitting the NSF. With compression, the NSF is more economical than an ANSI X12 837 to transport.

Readiness of Standard:

A)The NSF is a guideline for building electronic claims. The NSF supports policy requirements for users. The NSF defines processes using validation statements. The NSF provides a structured design for building claims.

B) The NSF was fully implemented for Medicare in 1991 and continues to be supported. The NSF has been implemented by about 200 other payers.

C)The NSF is available on the HCFA BPO bulletin board 410-786-0215. The file name is NSF.EXE and is located in area 3. There are no restrictions and it is free of charge.

D) The NSF implementation guide is built into the specifications and people may build standard claims from it.

E) Some payers provide a guide to identify payer specific requirements.

F) The NSF specifies conformity. Because it is in the public domain some people choose not to conform. This would easily be fixed if it was recognized by Federal statute. The specifications are clear and conformity is easy to achieve.

G) HCFA's Office of Analysis and Systems has developed a software conformance/enforcement tool for the NSF.

H) Other Indicators of Readiness: The NSF has been available since 1991.

Indicator Of Market Acceptance:

1)Medicare implemented the standard in 1991. Copies of the NSF are requested almost daily. The NSF is available on a bulletin board. Diskettes were previously distributed. Since the NSF is free of charge, the number of copies distributed is not maintained.

2)The following government agencies have implemented the NSF:

a) Medicare


c)Indian Health Services


e)Numerous Blue Shield plans and some 200 organizations use the NSF.

1) We are not aware of other countries that implemented the NSF.

2)We constantly receive praise from software vendors, clearinghouses and health care providers regarding the usefulness of the NSF and ease of implementation.

Level of Specificity:

A)The NSF is very detailed. Record descriptions exist, as well as, unambiguous data element definitions and format descriptions.

B)The NSF framework is detailed down to the smallest named unit of information.

C)The NSF does not reference or assume other standards to achieve more specificity.

D thru H) The NSF includes a code set for the place of service, podiatry codes, and type of service. The NSF assumes the following codes sets:



Health Care Procedure Codes (HCPCS)


Provide Specialty Codes


ICD-9 CM Procedure Codes

National Center For Health Statistics

CPT Codes


Physicians Current Procedure Terminology Manual


National Drug Code


Blue Book, Price Alert, National

Drug Data File

Claim Adjustment Reason Code

BCBS Association

Health Care Professional Shortage Area


National Association of Insurance Committee Code

NAIC Code List Manual

Medicare Inpatient/Outpatient Message


Investigational Device Exemption Number


Relationship With Other Standards:

A. The ANSI X12 837 health care claim is not suitable for use in an application program and must be translated into the NSF prior to claims processing. The NSF does not have to be translated and, in turn, reduces administrative costs.

Identifiable Costs:

The NSF is distributed free of charge. The NSF can be implemented within 3 to 6 months of receipt of the standard specifications. Implementation costs vary depending on how a payer implements the standard. Health care provider costs are minimal. The average cost for software is less than $200, and sometimes as little as $25.00. Implementation costs can range from $100,00 to $500,000. If a complete system rewrite is performed, the cost could be $500,000. If the change is at the interface, the cost could be less than $100,000. These costs include comprehensive systems testing.