Skip Navigation

NIS Description of Data Elements
The National (Nationwide) Inpatient Sample (NIS) is a set of longitudinal hospital inpatient databases included in the HCUP family. These databases are created by AHRQ through a Federal-State-Industry partnership.
 
 

NIS Description of Data Elements

The following links provide data elements descriptions for the National (Nationwide) Inpatient Sample (NIS).

Data element descriptions explain how the data element is coded in the HCUP databases, what the uniform values are, and State-specific coding practices. The descriptions are cumulative across all States and years of NIS data from 1988 to the current data year. Please note the following:

  • Not all data elements in the NIS are uniformly coded across States. Please check the "State Specific Notes" section for each data element before analysis.
  • Not all data elements in the NIS are available from every State.
  • Not all data elements are available each year. Please check the Availability of Data Elements by year table.

For a description of how HCUP data elements are coded, restriction on use, uniform values, and state-specific coding practices, check the corresponding boxes below and then click the "View Description of Data Elements".

Check the corresponding boxes and then click
NIS Core Data Elements NIS Hospital File Data Elements NIS Severity File Data Elements NIS Diagnosis and Procedure Groups File
ADAYWK*
AGE
AGEDAY*
AGE_NEONATE
AMONTH
ASOURCE*
ASOURCEUB92*
ASOURCE_X*
ATYPE*
AWEEKEND
D10CWT_U*
DCCHPRn*
DIED
DISCWT
DISCWT_U*
DISCWT10*
DISCWTcharge*
DISCWTcharge10*
DISP*
DISPUB04
DISPUB92*
DISPUniform
DQTR
DQTR_X*
DRG_NoPOA
DRG
DRG10*
DRG18*
DRG24
DRGVER
DSHOSPID*
DSNDX*
DSNPR*
DSNUM*
DSTYPE*
DXn
DXCCSn
DXSYS*
DXVn*
ECODEn
E_CCSn
ELECTIVE
FEMALE
HCUP_ED
HOSPBRTH
HOSPID*
HOSPST
HOSP_DIVISION
HOSP_NIS
HOSPSTCO*
KEY*
KEY_NIS
LOS
LOS_X*
MDC
MDC10*
MDC18*
MDC24
MDC_NoPOA
MDID_S*
MDNUM1_R*
MDNUM1_S*
MDNUM2_R*
MDNUM2_S*
NCHRONIC
NDX
NEOMAT
NECODE
NIS_STRATUM
NPR
ORPROC
PAY1
PAY1_N*
PAY1_X*
PAY2*
PAY2_N*
PAY2_X*
PCCHPRn*
PL_NCHS2006*
PL_NCHS
PL_UR_CAT4*
PointOfOriginUB04*
PointOfOrigin_X*
PRn
PRCCSn
PRDAYn
PROCESS*
PRSYS*
PRVn*
RACE
SEQ*
SEQ_SID*
SERVICELINE
SEX*
SURGID_S*
TOTCHG
TOTCHG_X*
TRAN_IN
TRAN_OUT
YEAR
ZIPINC*
ZIPINC_QRTL
ZIPINC4*
ZIPINC8*
AHAID*
DISCWT
DISCWT_F*
DISCWT_S*
DISCWT_U*
DISCWTcharge*
H_BEDSZ*
H_CONTRL
H_LOC*
H_LOCTCH*
H_REGION*
H_TCH*
HFIPSSTCO*
HOSP_BEDSIZE
HOSP_CONTROL*
HOSP_LOCATION*
HOSP_LOCTEACH
HOSP_LPNFTEAPD*
HOSP_MHSCLUSTER*
HOSP_MHSMEMBER*
HOSP_NAFTEAPD*
HOSP_DIVISION
HOSP_NIS
HOSP_OPSURGPCT*
HOSP_REGION
HOSP_RNFTEAPD*
HOSP_RNPCT*
HOSP_TEACH*
HOSPADDR*
HOSPCITY*
HOSPID*
HOSPNAME*
HOSPST*
HOSPSTCO*
HOSPWT*
HOSPWT_F*
HOSPWT_S*
HOSPWT_U*
HOSPZIP*
IDNUMBER*
LOCTEACH*
N_DISC_F*
N_DISC_S*
N_DISC_U
N_HOSP_F*
N_HOSP_S*
N_HOSP_U
NIS_STRATUM
S_DISC_S*
S_DISC_U
S_HOSP_S*
S_HOSP_U
ST_BEDSZ*
ST_OWNER*
ST_REG*
STRAT_ST*
STRATUM*
TOTAL_DISC
TOTDSCHG*
YEAR
APRDRG
APRDRG_Risk_Mortality
APRDRG_Severity
APSDRG*
APSDRG_Charge_Weight*
APSDRG_LOS_Weight*
APSDRG_Mortality_Weight*
CM_AIDS
CM_ALCOHOL
CM_ANEMDEF
CM_ARTH
CM_BLDLOSS
CM_CHF
CM_CHRNLUNG
CM_COAG
CM_DEPRESS
CM_DM
CM_DMCX
CM_DRUG
CM_HTN_C
CM_HYPOTHY
CM_LIVER
CM_LYMPH
CM_LYTES
CM_METS
CM_NEURO
CM_OBESE
CM_PARA
CM_PERIVASC
CM_PSYCH
CM_PULMCIRC
CM_RENLFAIL
CM_TUMOR
CM_ULCER
CM_VALVE
CM_WGHTLOSS
DS_DX_Category1*
DS_Stage1*
DS_LOS_level*
DS_LOS_Scale*
DS_Mrt_Level*
DS_Mrt_Scale*
DS_RD_Level*
DS_RD_Scale*
HOSP_NIS
HOSPID*
KEY*
KEY_NIS
BODYSYSTEMn
CCSMGNn*
CCSMSPn*
CHRONn
CHRONBn*
DXMCCSn
ECCSMGNn*
E_MCCSn
HOSPID*
HOSP_NIS
KEY*
KEY_NIS
PCLASSn
PRMCCSn
Check the corresponding boxes and then click

* This data element is discontinued. Please refer to the Availability of Data Elements by year table to see the year it was discontinued.


Internet Citation: NIS Description of Data Elements. Healthcare Cost and Utilization Project (HCUP). November 2016. Agency for Healthcare Research and Quality, Rockville, MD. www.hcup-us.ahrq.gov/db/nation/nis/nisdde.jsp.
Are you having problems viewing or printing pages on this Website?
If you have comments, suggestions, and/or questions, please contact hcup@ahrq.gov.
Privacy Notice, Viewers & Players
Last modified 11/7/16