From July 2015 - December 2017, some Maryland hospitals under-reported HCPCS and CPT drug codes (specifically J-codes) and the associated units.

The order of the CPT codes in CPTn does not pertain to the order of the detailed charges (CHGn) and revenue codes (REVCDn).

Maryland does not provide ICD-9-CM procedure codes on outpatient data, so the CPTn vector is placed on the core file.

CPT1 is 100% missing for one hospital in the 2010 MD SASD and SEDD.

Missouri reports a mixture of ICD-9-CM procedure codes (3-4 digit codes) and CPT-4/HCPCS procedure codes (5 digit codes) in one array in their ambulatory surgery files. The reported procedures are split into the HCUP array that holds ICD-9-CM procedures (PRn) and the HCUP array that holds CPT-4/HCPCS procedures (CPTn), as appropriate.

The principal procedure is retained in the principal position:

• If the reported principal procedure is less than 5 digits long, then PR1 = the reported principal procedure and CPT1 = blank.
• If the reported principal procedure is 5 digits long, then CPT1 = the reported principal procedure and PR1 = blank.

The secondary procedures are packed into the secondary procedures so that there are no gaps in the HCUP arrays:

• If the reported secondary procedure is less than 5 digits long, then the reported secondary procedure is placed in the first open position starting at PR2.
• If the reported principal procedure is 5 digits long, then the reported secondary procedure is placed in the first open position starting at CPT2.

No secondary procedures are placed into the principal position.

Only the procedure dates for the ICD-9-CM procedures could be retained on the HCUP files in the array PRDATEn. Procedure days (PRDAYn) for the ICD-9-CM procedures are calculated from the reported procedure dates and admission date.

The order of the CPT codes in CPTn pertains to the order of the detailed charges (CHGn), revenue codes (REVCDn), and units (UNITn).

Prior to 2008, reporting of CPTs was not mandated; it was a voluntary effort. CPT codes were reported only when the payer required a CPT code to process the claim. New York did not consider the quality of the CPT information to be reliable and did not use CPT codes in their analyses. New York used only the ICD-9-CM codes for analyses.

This data element was provided by Utah for ambulatory surgery (AS) records and not supplied for the emergency department (ED) records. However, when AS records with evidence of ED services were placed in the SEDD during HCUP processing, this data element was also added to the SEDD. Therefore, very few records in the SEDD will contain values for this data element.

Wisconsin provided both an array of CPT\HCPCS codes (CPTn) as well as Line item CPT\HCPCS procedure codes (CPTHCPCS), and we kept both during processing. Some surgery codes are only in the CPTn array, while other CPT\HCPCS codes are only in the Line item CPT\HCPCS procedure codes (CPTHCPCS). Therefore, the CPTn array on the Core File and the CPTHCPCS data element from the Charge Detail File should be used together to get a complete set of CPT\HCPCS codes for each discharge.