NDC Crosswalk Questions and Answers
1. What is the conversion factor and how is it used?
The DME MAC receives electronic claims in the NCPDP billing format. The conversion factor converts the NCPDP billing units to HCPCS billing units for Medicare claims processing.
Conversion Factor Example:
Suppose an NDC has a strength of 5mg/ml and the NCPDP billing unit is “ML”. One NCPDP billing unit would contain 5mg. If the corresponding HCPCS unit is “per mg”, then one NCPDP billing unit would contain 5 HCPCS units. (One ML contains 5 mg)
2. I am trying to bill a drug whose NDC is end-dated on the crosswalk. How can I bill this now?
The information on the crosswalk is received from the Redbook file, which is updated monthly. Contact your DME MAC with billing concerns.
3. What are the columns definitions?
NDC: The National Drug Code (NDC) serves as a universal product identifier for human drugs and biologics. Each NDC must be reported as an 11-digit code unique to the manufacturer of the specific drug or product.
NDC Mod: Healthcare Common Procedure Coding System (HCPCS) Level II codes may require the use of modifiers to capture the exact nature of the service. The Level II modifiers are two alphabetic or alphanumeric digits.
HCPCS: HCPCS codes are used by Medicare and monitored by the CMS. HCPCS Level II codes are assigned to every service a medical practitioner provides to a Medicare patient including durable medical equipment, prosthetics and orthotics supplies. These codes are an alpha character followed by four numbers.
HCPCS Mod: HCPCS Level II codes may require the use of modifiers to capture the exact nature of the service. The Level II modifiers are two alphabetic or alphanumeric digits.
Relationship Start Date: The relationship start date between the NDC and HCPCS code. A new relationship start date is listed whenever any of the following occur:
- New HCPCS code added
- New NDC code added
- NDC is reactivated
- HCPCS code change description that adds a new NDC relationship for the HCPCS code
Relationship End Date: The relationship end date between the NDC and HCPCS code. A new relationship end date is listed whenever any of the following occur:
- HCPCS Code Deletion
- NDC Withdrawn
- NDC deactivated
HCPCS Description: The long description of the HCPCS Level II code
NDC Label: The following information may be present in this field:
- Product name given to the product by the manufacturer
- Additional information on product characteristics not captured in other fields may be provided
- Details of packaging and preparation, such as “dialpak,” “fliptop vial,” “premixed,” and “micronized.” Flavors may be listed when applicable. Also shown, when appropriate, is information on package dimensions -- for example, “2 x 5 x 10”—and descriptive material such as “sulfite-free,” “refill,” and “non-drowsy.”
- The product strength listed in alphabetical order of the active ingredients. For combination products, a hyphen may separate the individual strengths of the active ingredients. For example, the strength of acetaminophen with codeine is expressed as “325 mg-30 mg.”
Number of Items in NDC Package: The amount of product contained in the package as defined by the billing unit standard of the National Council for Prescription Drug Programs (NCPDP).
NDC package Measure: The total size of the package in volume or number of units contained.
NDC Package Type: The container or package used for the drug product, i.e. vial, bottle, bag, etc.
Route of Administration: Identifies the product’s intake or application method.
NDC Billing Units: The unit of measure when billing NDC units. Provides the two-character abbreviation corresponding to valid units of measure per the NCPDP standard. The only valid values for this field are “ea,” “gm,” or “ml.”
HCPCS Amount: The amount of product in a HCPCS billing unit (may be found in the HCPCS description).
HCPCS Measure: The number of HCPCS units in one NCPDP billing unit.
CF: The Conversion Factor (CF) is the rate to convert HCPCS quantity to NDC quantity. This is derived by dividing the NDC amount by the HCPCS amount.
Start Date #1: The Start Date #1 is the relationship start date between the NDC and HCPCS code.
End Date #1: The End Date #1 is the relationship end date between the NDC and HCPCS code.