U.S. flag

An official website of the Department of Health & Human Services

AHRQ: Agency for Healthcare Research and Quality
HEALTHCARE COST & UTILIZATION PROJECT

User Support

Do Your own analysis
Explore Expert Research & Limited Datasets

KID Description of Data Elements

The following links provide data elements descriptions for the Kids' Inpatient Database (KID).

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 KID data from 1997 to the current data year. Please note the following:

  • Not all data elements in the KID are uniformly coded across States. Please check the "State Specific Notes" section for each data element before analysis.
  • Not all data elements in the KID are available from every State.
  • Not all data elements are available each year. Please check the Availability of Data Elements by year (PDF file, 120 KB) 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

Abbreviations: DX, diagnosis; PR, procedure; Q1, discharge quarter 1; Q3, discharge quarter 3; Q4, discharge quarter 4.

HCUP Data Element Descriptive Title Years File(s)
Data elements change frequently, and are only current as of the date generated.
Admission day of week 1997 Core
Age in years at admission 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Age in days (when AGE is less than 1 year) 1997, 2000, 2003, 2006, 2009 Core
Age in months (when AGE is less than 11 years) 1997, 2000, 2003, 2006, 2009 Core
Neonatal age (first 28 days after birth) indicator 2012, 2016, 2019 Core
AHA hospital identifier 2000, 2003, 2006, 2009 Hospital
Admission month 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
All Patient Refined DRG 2003, 2006, 2009, 2012, 2016, 2019 Severity
All Patient Refined DRG: Risk of Mortality Subclass 2003, 2006, 2009, 2012, 2016, 2019 Severity
All Patient Refined DRG: Severity of Illness Subclass 2003, 2006, 2009, 2012, 2016, 2019 Severity
All-Payer Severity-adjusted DRG 2003, 2006, 2009 Severity
All-Payer Severity-adjusted DRG: Charge Weight 2003, 2006, 2009 Severity
All-Payer Severity-adjusted DRG: Length of Stay Weight 2003, 2006, 2009 Severity
All-Payer Severity-adjusted DRG: Mortality Weight 2003, 2006, 2009 Severity
Admission source, uniform coding 1997, 2000, 2003, 2006, 2009 Core
Admission source, as received from source 2000, 2003, 2006, 2009 Core
Admission source, (UB-92 standard coding) 2003, 2006, 2009 Core
Admission type 1997, 2000, 2003, 2006, 2009 Core
Admission day is on a weekend 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Birth weight in grams 2000, 2003, 2006, 2009 Core
Clinical Classification Software (CCS) for Mental Health and Substance Abuse - General 2006 DX_PR_Grps
Clinical Classification Software (CCS) for Mental Health and Substance Abuse - Detail 2006 DX_PR_Grps
Weight to pediatric non-births in universe for estimates other than total charges 2000 Hospital
Weight to pediatric non-births in universe for total charge estimates 2000 Hospital
Weight to pediatric non-births in universe 1997 Hospital
Chronic Condition Indicators - body system 2006, 2009, 2012 DX_PR_Grps
ICD-9-CM Chronic Condition Indicators 2006, 2009, 2012 DX_PR_Grps
AHRQ comorbidity measure for ICD-9-CM codes: acquired immune deficiency syndrome 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: alcohol abuse 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: deficiency anemias 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: rheumatoid arthritis/collagen vascular diseases 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: chronic blood loss anemia 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: congestive heart failure 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: chronic pulmonary disease 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: coagulopathy 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: depression 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: diabetes, uncomplicated 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: diabetes with chronic complications 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: drug abuse 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: hypertension (combine uncomplicated and complicated) 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: hypothyroidism 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: liver disease 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: lymphoma 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: fluid and electrolyte disorders 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: metastatic cancer 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: other neurological disorders 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: obesity 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: paralysis 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: peripheral vascular disorders 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: psychoses 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: pulmonary circulation disorders 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: renal failure 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: solid tumor without metastasis 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: peptic ulcer disease excluding bleeding 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: valvular disease 2003, 2006, 2009, 2012 Severity
AHRQ comorbidity measure for ICD-9-CM codes: weight loss 2003, 2006, 2009, 2012 Severity
Weight to complicated births in universe for estimates other than total charges 2000 Hospital
Weight to complicated births in universe 1997 Hospital
Weight to complicated births in universe for total charge estimates 2000 Hospital
Clinical Classifications Software: diagnosis classification 1997 Core
Died during hospitalization 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Weight to discharges in the universe 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Weight to discharges in universe 1997 Core, Hospital
Weight to discharges in the universe for national estimates of total charge in 2000. 2000 Core
Disposition of patient 1997 Core
Disposition of patient, UB04 standard coding 2009 Core
Disposition of patient, UB92 coding 2003, 2006, 2009 Core
Disposition of patient, uniform coding 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Discharge quarter 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Discharge quarter, as received from data source 2006, 2009 Core
DRG in use on discharge date 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
DRG in use on discharge date, calculated without POA 2009, 2012, 2016, 2019 Core
DRG, Version 10 1997 Core
DRG, Version 18 2000, 2003 Core
DRG, Version 24 2006, 2009, 2012 Core
DRG or MS-DRG grouper version used on discharge date 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Disease Staging: Principal Disease Category 2003, 2006, 2009 Severity
Disease Staging: Length of Stay Level 2003, 2006 Severity
Disease Staging: Length of Stay Scale 2003, 2006 Severity
Disease Staging:Mortality Level 2003, 2006 Severity
Disease Staging: Mortality Scale 2003, 2006 Severity
Disease Staging: Resource Demand Level 2003, 2006 Severity
Disease Staging: Resource Demand Scale 2003, 2006 Severity
Disease Staging: Stage of Principal Disease Category 2003, 2006, 2009 Severity
Data source hospital number 2000, 2003, 2006, 2009 Core
Clinical Classifications Software (CCS): ICD-9-CM diagnosis classification 2000, 2003, 2006, 2009, 2012 Core
Multi-Level CCS for ICD-9-CM Diagnoses 2009,2012 DX_PR_Grps
ICD-9-CM Diagnosis 1997, 2000, 2003, 2006, 2009, 2012 Core
Clinical Classifications Software Refined (CCSR): ICD-10-CM Diagnosis Classification within Body System AAA 2019 DX_PR_GRPS
Version of the Clinical Classifications Software Refined (CCSR) for ICD-10-CM diagnosis codes 2019 DX_PR_GRPS
Default Clinical Classifications Software Refined (CCSR) for principal/first-listed ICD-10-CM diagnosis 2019 DX_PR_GRPS
Diagnosis codes ICD version indicator 2016 Core
Diagnosis validity flag: Diagnosis n 1997 Core
Clinical Classifications Software (CCS) for ICD-9-CM External Cause of Injury Code 2003, 2006, 2009, 2012 Core
Multi-Level CCS for ICD-9-CM External Cause of Injury Code 2009, 2012 DX_PR_Grps
Clinical Classification Software (CCS) for Mental Health and Substance Abuse - General 2006 DX_PR_Grps
ICD-9-CM External Cause of Injury Code 2003, 2006, 2009, 2012 Core
Elective versus non-elective admission 2003, 2006, 2009, 2012, 2016, 2019 Core
Indicator of sex 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Bedsize of hospital (definition used prior to 1998) 1997 Hospital
Number of births in HCUP frame hospitals in STRATUM 1997, 2000 Hospital
Number of pediatric non-births in HCUP frame hospitals in STRATUM 1997, 2000 Hospital
Number of pediatric non-births in HCUP frame hospitals in STRATUM 1997, 2000 Hospital
Control/ownership of hospital 1997, 2009, 2012, 2016, 2019 Hospital
Number of discharges in HCUP frame hospitals in STRATUM 1997, 2000 Hospital
Number of hospitals in HCUP frame hospitals in STRATUM 1997, 2000 Hospital
Location of hospital (definition used prior to 1998) 1997 Hospital
Location/teaching status of hospital (definition used prior to 1998) 1997 Hospital
Hospital census region 1997 Hospital
Hospital teaching status (definition used prior to 1998) 1997 Hospital
Number of uncomplicated births in HCUP frame hospitals in STRATUM 1997, 2000 Hospital
HCUP indicator of emergency department record 2009, 2012, 2016, 2019 Core
Hospital FIPS State/County code 2006, 2009 Hospital
Bedsize of hospital 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Control/ownership of hospital 2000, 2003, 2006, 2009 Hospital
Census Division of hospital (STRATA) 2012 Hospital
KID hospital number 2012, 2016, 2019 Core, Hospital, Severity, DX_PR_Grps
Location (urban/rural) of hospital 2000, 2003, 2006, 2009 Hospital
Location/teaching status of hospital 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
LPN FTEs per 1000 adjusted inpatient days 2009 Hospital
Multi-hospital system cluster code 2009 Hospital
Multi-hospital system membership 2009 Hospital
Nurse aides per 1000 adjusted inpatient days 2009 Hospital
Percentage of all surgeries performed in the outpatient setting 2009 Hospital
Region of hospital 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core (beginning in 2012), Hospital
RN FTEs per 1000 adjusted inpatient days 2009 Hospital
Percentage of RNs among all nurses (RNs and LPNs) 2009 Hospital
Teaching status of hospital 2000, 2003, 2006, 2009 Hospital
Hospital address from AHA Annual Survey 2000, 2003, 2006, 2009 Hospital
ICD-9-CM diagnosis indicates in-hospital birth 1997, 2000, 2003, 2006, 2009, 2012 Core
Hospital city from AHA Annual Survey 2000, 2003, 2006, 2009 Hospital
HCUP hospital identification number 2000, 2003, 2006, 2009 Core, Hospital, Severity, DX_PR_Grps
Hospital name from AHA Annual Survey 2000, 2003, 2006, 2009 Hospital
KID hospital number 1997 Core, Hospital
Hospital State postal code 2000, 2003, 2006, 2009 Core, Hospital
Hospital modified FIPS state/county code 2000, 2003, 2006, 2009 Core (2000), Hospital (2003, 2006, 2009)
Hospital zip code from AHA Annual Survey 2000, 2003, 2006, 2009 Hospital
ICD-10-CM Birth Indicator 2019 Core
ICD-10-CM Delivery Indicator 2019 Core
ICD-10-CM Diagnosis 2016, 2019 Core
ICD-10-CM External Cause of Morbidity Code 2016 Core
ICD-10-CM diagnosis indicates in-hospital birth 2016, 2019 Core
Injury ICD-10-CM diagnosis reported on record 2019 Core
Multiple ICD-10-CM injuries reported on record 2019 Core
Number of ICD-10-CM diagnoses on this discharge 2016, 2019 Core
Number of ICD-10-CM External Cause of Morbidity codes on this record 2016 Core
Number of ICD-10-PCS procedures on this discharge 2016, 2019 Core
ICD-10-PCS Procedure 2016, 2019 Core
Service line based on ICD-10-CM/PCS codes 2019 Core
ICD-10-CM diagnosis indicates a normal uncomplicated in-hospital birth 2016, 2019 Core
Modified AHA hospital identifier 2000, 2003, 2006, 2009 Hospital
Unique record identifier 2000 Core, Severity
Stratum used to post-stratify hospital 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core, Hospital
Length of stay, cleaned 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Length of stay, as received from data source 1997, 2000, 2003, 2006, 2009 Core
MDC in effect on discharge date 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
MDC in use on discharge date, calculated without POA 2009, 2012, 2016, 2019 Core
MDC, Version 10 1997 Core
MDC, Version 18 2000, 2003 Core
MDC, Version 24 2006, 2009, 2012 Core
Synthetic attending physician number 1997, 2000 Core
Physician 1 number (re-identified) 2003, 2006, 2009 Core
Physician 2 number (re-identified) 2003, 2006, 2009 Core
Number of universe births in STRATUM 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Number of universe discharges in the stratum 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Number of universe hospitals in the stratum 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
NACHRI hospital type 1997, 2000, 2003, 2006, 2009 Hospital
ICD-9-CM Number of chronic conditions 2009, 2012 Core
Number of ICD-9-CM diagnoses on this discharge 1997, 2000, 2003, 2006, 2009, 2012 Core
Number of ICD-9-CM External of Cause of Injury Codes on this Record 2003, 2006, 2009, 2012 Core
Neonatal and/or maternal ICD-9-CM DX and/or PR 1997, 2000, 2003, 2006, 2009, 2012 Core
Number of ICD-9-CM procedures on this discharge 1997, 2000, 2003, 2006, 2009, 2012 Core
Major operating room ICD-9-CM procedure indicator 2009, 2012 Core
Expected primary payer, uniform 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Expected primary payer, nonuniform 1997 Core
Expected primary payer, as received from data source 2000, 2003, 2006, 2009 Core
Expected secondary payer, uniform 1997, 2000, 2003, 2006, 2009 Core
Expected secondary payer, nonuniform 1997 Core
Expected secondary payer, as received from data source 2000, 2003, 2006, 2009 Core
Clinical Classifications Software: procedure classification 1997 Core
Procedure Classes Refined for ICD-10-PCS procedure codes 2006, 2009, 2012, 2019 DX_PR_Grps
Version of the Procedure Classes Refined for ICD-10-PCS procedure codes 2019 DX_PR_Grps
Major operating room ICD-10-PCS procedure indicator 2019 Core
Number of discharges, 20 years old or younger, from this hospital in the SID 2000, 2003, 2006, 2009 Hospital
Percentage of hospital discharges, 20 years old or younger 2000, 2003, 2006, 2009 Hospital
Patient Location: NCHS Urban-Rural Code 2006, 2009, 2012, 2016, 2019 Core
Patient Location: Urban-Rural 4 Categories 2003 Core
Point of origin for admission or visit, as received from source 2009 Core
Point of origin for admission or visit, UB04 standard coding 2009 Core
ICD-9-CM Procedure 1997, 2000, 2003, 2006, 2009, 2012 Core
Clinical Classifications Software (CCS) for ICD-9-CM Procedures 2000, 2003, 2006, 2009, 2012 Core
Clinical Classifications Software Refined (CCSR): ICD-10-PCS Procedure Classification within Clinical Domain aaa 2019 DX_PR_GRPS
Version of the Clinical Classifications Software Refined (CCSR) for ICD-10-PCS procedure codes 2019 DX_PR_GRPS
Number of days from admission to procedure n 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Multi-Level CCS for ICD-9-CM Procedures 2009, 2012 DX_PR_Grps
Validity Flag: Procedure n 1997 Core
Procedure codes ICD version indicator 2016 Core
Race/ethnicity of patient 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
HCUP record number 1997, 2003, 2006, 2009, 2012, 2016, 2019 Core, Severity, DX_PR_Grps
Number of sample births in STRATUM 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Number of pediatric non-births sampled in the hospital 1997, 2000 Hospital
Number of sample pediatric non-births in STRATUM 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Number of complicated births sampled in the hospital 1997, 2000 Hospital
Number of sample complicated births in STRATUM 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Number of discharges in the sample for the stratum 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Number of hospitals in the sample for the stratum 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Number of uncomplicated births sampled in the hospital 1997, 2000 Hospital
Number of sample uncomplicated births in STRATUM 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Hospital
Sex of the patient 1997 Core
Stratum used to post-stratify hospital 1997 Hospital
Synthetic primary surgeon number 1997, 2000 Core
Number of hospital discharges in the sample 2000, 2003, 2006, 2009 Hospital
Total charges, cleaned 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core
Total charges, as received from data source 1997, 2000, 2003, 2006, 2009 Core
Total hospital discharges 1997 Hospital
Indicator of a transfer into the hospital 2009, 2012, 2016, 2019 Core
Transfer out indicator 2012, 2016, 2019 Core
ICD-9-CM diagnosis indicates a normal uncomplicated in-hospital birth 1997, 2000, 2003, 2006, 2009, 2012 Core
Weight to uncomplicated births in universe for estimates other than total charges 2000 Hospital
Weight to uncomplicated births in universe for total charge estimates 2000 Hospital
Weight to uncomplicated births in universe 1997 Hospital
Calendar year 1997, 2000, 2003, 2006, 2009, 2012, 2016, 2019 Core, Hospital
Median household income for patient's ZIP Code (based on 1999 demographics) 2000 Core
Median household income for patient's ZIP Code (based on current year) 2003, 2006, 2009, 2012, 2016, 2019 Core
Median income for patient's ZIP Code (4 categories) 1997 Core

Abbreviations: DX, diagnosis; PR, procedure; Q1, discharge quarter 1; Q3, discharge quarter 3; Q4, discharge quarter 4.

Check the corresponding boxes and then click
Internet Citation: KID Description of Data Elements. Healthcare Cost and Utilization Project (HCUP). February 2023. Agency for Healthcare Research and Quality, Rockville, MD. www.hcup-us.ahrq.gov/db/nation/kid/kiddde.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 2/8/23