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Central Distributor SASD: Description of Data Elements

 
PRDAYn - Number of days from admission to procedure n
 
Documentation Sections:
General Notes
Uniform Values
State Specific Notes
General Notes
 

The day on which the procedure is performed (PRDAYn) is calculated from the procedure date (PRDATEn) and the admission date (ADATE) with the following exceptions:

  • PRDAYn is set to the supplied day of principal procedure if the procedure day cannot be calculated (ADATE and/or PRDATEn is missing or invalid). Note: the supplied day of procedure is used only if it distinguishes between a procedure performed on the first day (procedure day = 0) and no procedure day (procedure day is missing).
  • PRDAYn is missing (.) if the procedure day cannot be calculated and the supplied procedure day is missing.
  • PRDAYn is invalid (.A) if the procedure day cannot be calculated and the supplied procedure day is nonnumeric.
  • If the data source does not supply either admission date (ADATE) and procedure date (PRDATEn), or the day of procedure, then beginning in the 1998 data PRDAYn is not present on the HCUP files. In the 1988-1997 data, PRDAYn is retained on the HCUP files and is set to unavailable from source (.B).
  • PRDAYn is inconsistent (.C) if
    • there is a day of procedure without a coded procedure (ED7nn), or
    • the day of procedure is not during the stay (EPRDAY01 beginning in the 1998 data and ED8nn in the 1988-1997 data).

Edit checks ED7nn are only performed on the 1988-1997 data. Beginning in the 1998 data, the procedure date without a coded procedure is discarded.

The procedure date vector (PRDATEn) is shifted with the ICD-9-CM procedure codes (PRn) when the procedure vector is packed.

Some sources do not require procedure dates/days for minor or diagnostic procedures which are considered UHDDS class 3 and class 4 procedures. The UHDDS system grouped ICD-9-CM procedure codes into four classes differentiated by impact on either the well-being of the patient or on the health care system. The criteria used to classify procedures included procedural risk, anesthetic risk, and the need for highly trained personnel, special facilities or special equipment. The classes are:

  • Class 1: Surgical
  • Class 2: Significant procedure (date required)
  • Class 3: Significant procedure (date not required)
  • Class 4: Minor procedures not normally coded on inpatient data.

PRDAY1 is present on the NIS from 1988 onward; secondary procedures (PRDAY2-15) are present on the NIS beginning in 1998.

 
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Uniform Values
 
VariableDescriptionValueValue Description
PRDAYnNumber of days from admission to procedure n-4 - -1Days prior to admission
0Day of admission
1 - LOS+3Days after admission (In rare instances in the 2008-2015 data, the maximum of LOS+3 was not enforced)
.Missing
.AInvalid
.BUnavailable from source (coded in 1988-1997 data only)
.CInconsistent: beginning with 1998 data, EPRDAY01; in 1998-1997 data, ED7nn, ED8nn
 
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State Specific Notes

Colorado

Beginning in 2010, Colorado began supplying secondary procedure dates. These fields are used to calculate PRDAYn.

Prior to 2010, only PRDAY1 is available because Colorado did not report secondary procedure days or dates.

Only the calculated day of principal procedure could be used to assign PRDAY1 because Colorado did not supply principal procedure day.



Indiana

Prior to 2010, only PRDAY1 is available because Indiana did not report secondary procedure days or dates. Beginning in 2010, Indiana started supplying secondary procedure dates.

Only the calculated day of procedure could be used to assign PRDAYn because Indiana did not supply this information.



Minnesota

Only the calculated day of procedure could be used to assign PRDAYn because Minnesota did not supply day of procedure.



Missouri

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.



Nebraska

Only the calculated day of procedure could be used to assign PRDAYn because Nebraska did not supply day of procedure.



Nebraska

Beginning in 2009, Nebraska no longer provides ICD-9-CM procedure codes.



New Jersey

Only the calculated day of procedure could be used to assign PRDAY because New Jersey did not supply the day of procedure.



New York

Beginning with the 2008 data, ICD-9-CM procedure codes were 100% missing and will no longer be available.

Beginning with the 2008 data, the HCUP data element PRDAYn is missing (.) for AIDS/HIV patients. New York identifies AIDS/HIV records by ICD-9-CM diagnosis code, DRG, or MS-DRG:

  • An admitting, principal or any secondary diagnosis of "042", "043", "044", "7958", "27910", "27919", "2793", "1363", "79571", "07951", "07952", "07953", "V017" or "V08".
  • A DRG of 488 through 490 (prior to October 2007) or MS-DRG of 700 through 716 (beginning in October 2007).

Please note that the admitting diagnosis is not retained in the HCUP databases prior to 2012.



Utah

Only the calculated day of procedure could be used to assign PRDAYn because Utah did not report day of procedure.



Wisconsin

Principal procedure day is only required for major procedures (defined below). Procedure days are set to missing for all other cases.

Major procedures are defined as Class 1 or 2 procedures. The UHDDS system grouped ICD-9-CM procedure codes into four classes differentiated by impact on either the well-being of the patient or on the health care system. The criteria used to classify procedures included procedural risk, anesthetic risk, and the need for highly trained personnel, special facilities or special equipment. The classes are:

  • Class 1: Surgical
  • Class 2: Significant procedure (date required)
  • Class 3: Significant procedure (date not required)
  • Class 4: Minor procedures not normally coded on inpatient data

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Internet Citation: HCUP Central Distributor SASD Description of Data Elements - All States. Healthcare Cost and Utilization Project (HCUP). April 2008. Agency for Healthcare Research and Quality, Rockville, MD. www.hcup-us.ahrq.gov/db/vars/sasddistnote.jsp?var=prdayn.
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Last modified 4/11/08