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Central Distributor SASD: Description of Data Elements

CPTM1_n - First CPT-4/HCPCS modifier
Documentation Sections:
General Notes
Uniform Values
State Specific Notes
General Notes

Two-digit modifiers for CPT and HCPCS codes indicate that a service or procedure that has been performed has been altered by some specific circumstances, but not changed in its definition. Examples include the following:

  • Modifier 22 - Unusual Service: The service provided is greater than that usually required for the listed procedure. For example, a speech and language evaluation (CPT 92506) that requires twice the amount of time as "typical."
  • Modifier RT and LT - Side of body: Indicates service performed on the right or left side of the body.
  • Modifier 76 and 77 - Repeat Procedure: Modifier 76 indicates that the procedure was repeated by the same physician in the same day. Modifier 77 indicates that the procedure was repeated by another physician.

More than one modifier may be used for an individual HCPCS/CPT code. When billing HCPCS/CPT codes with more than one modifier, the functional modifier is supposed to be placed in the first modifier field. Informational modifiers should be placed in the second modifier field. For example, if a physician billed a CPT code with both the modifier 22 for unusual services and the modifier LT to indicate the procedure was performed on the left side of the body, the 22 would be placed in the first modifier field and the LT would be placed in the second modifier field.

During HCUP processing, modifiers are validated. Invalid modifiers are set to "i".

Uniform Values
VariableDescriptionValueValue Description
CPTM1_nFirst CPT-4/HCPCS modifier2(a)CPT Modifier
State Specific Notes


In the HCUP Central Distributor SASD and SEDD prior to 2012, if the array of CPT modifiers have missing codes in the middle of the array (e.g., CPTM1_1 is reported, CPTM1_2 is missing, and CPTM1_3 is reported), then the CPT modifiers may not have been moved with the corresponding CPT code when the array elements were re-ordered.


For 2005, the CPT modifier array for Wisconsin will only identify bilateral procedure codes. Wisconsin provided a Bilateral Procedure Indicator for each CPT field on the outpatient source files. These indicators identified bilateral procedures based upon submission of modifier "50" on outpatient surgery or emergency department records. During HCUP processing, the HCUP variable CPTM1_n was coded with the value "50" whenever this indicator was set to "Y". No other values will be found in the modifier array for Wisconsin SASD or SEDD.

Beginning in 2006, Wisconsin provided CPT modifiers and the Bilateral Procedure Indicators are no longer used.


Internet Citation: HCUP Central Distributor SASD Description of Data Elements - All States. Healthcare Cost and Utilization Project (HCUP). May 2024. Agency for Healthcare Research and Quality, Rockville, MD.
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Last modified 5/22/24