User Support

November 2022

Audrey J. Weiss, Ph.D., Lan Liang, Ph.D., and Kimberly Martin, Ph.D.


Introduction

Children are hospitalized for a variety of reasons, including birth, appendicitis, and respiratory conditions such as asthma and pneumonia.^1,2 Pediatric hospitalizations have been declining in recent years.² Between 2004 and 2019, the number and rate of inpatient stays for children aged 0–17 years decreased by 20 percent.³ Factors such as a shift to outpatient services as well as increased pediatric care coordination (e.g., through accountable care organizations and patient-centered medical homes) may be changing the nature of pediatric hospitalizations.^4,5 Bucholz et al.⁶ found that both pediatric admissions involving complex chronic conditions and pediatric readmissions increased between 2010 and 2016. Given these changes, understanding the current characteristics of and reasons for inpatient hospitalizations among children is important to inform pediatric clinical practice as well as health policy initiatives aimed at improving children's health.

This Healthcare Cost and Utilization Project (HCUP) Statistical Brief presents statistics on hospital stays among children and adolescents, aged 0–17 years, using weighted national estimates from the 2019 National Inpatient Sample (NIS) and State-level estimates from the 2019 State Inpatient Databases (SID). The distribution of hospital stays and aggregate costs by pediatric age group is provided. Characteristics of children's hospital stays are presented by pediatric age group and primary expected payer. The most common principal diagnoses are provided by pediatric age group. Finally, characteristics of pediatric hospitalizations are presented for 48 States and the District of Columbia. Because of the large sample size of the NIS and SID data, small differences can be statistically significant. Thus, only differences greater than or equal to 10 percent are discussed in the text.

Findings

Characteristics of pediatric hospitalizations, 2019
Figure 1 shows total hospital stays and aggregate hospital costs among children in 2019.

• The majority of pediatric hospital stays and associated aggregate hospital costs were for newborns and infants.
  
  Newborns and infants under 1 year of age constituted the largest proportion of the 5.2 million total pediatric hospitalizations (76.7 percent) and $46.4 billion aggregate pediatric hospital costs (60.5 percent) in 2019. For other pediatric age groups, the proportion of aggregate hospital costs was higher than the proportion of hospital stays.

Table 1 presents characteristics of inpatient hospitalizations among children in 2019.

Table 1. Characteristics of hospital stays among children aged 0–17 years by age group, 2019

• Infants under 1 year of age had the highest length of stay and mean hospital costs.
  
  The length of pediatric stays was highest among infants under 1 year of age (6.3 days) and lowest among neonates and children under 10 years of age (3.8–4.1 days). Mean hospital costs also were highest among infants under 1 year of age ($24,100) but lowest among neonates ($5,700).

The percentage of stays with a primary expected payer of Medicaid decreased with children's age, from 60.6 percent among infants to 50.6 percent among adolescents aged 15–17 years, but the percentage was lowest for neonates (44.7 percent). Conversely, the percentage of stays with private insurance increased with children's age, from 33.2 percent among infants to 42.1 percent among adolescents aged 15–17 years, but the percentage was highest for neonates (46.9 percent). Neonates also had the highest percentage of stays that were expected to be self-pay/no charge (5.4 percent vs. 2.5–3.3 percent for other age groups).

The percentage of pediatric stays for females ranged from 42.5 percent among infants under 1 year of age to 60.2 percent among adolescents aged 15–17 years.

Except for neonates, approximately half or more of pediatric stays were admitted through the emergency department (ED), ranging from 48.4 percent for adolescents aged 15–17 years to 62.9 percent for children aged 1–4 years. Very few pediatric stays for neonates (1.4 percent) originated in the ED.

• For neonates, the average length of stay, average costs, and percentage of stays admitted through the ED were highest for stays with Medicaid as the primary expected payer.
  
  For neonatal stays, the average length of stay ranged from 2.6 days for self-pay/no charge to 4.3 days for stays expected to be paid by Medicaid. Similarly, average costs ranged from $2,700 for self-pay/no charge to $6,500 for Medicaid. Finally, the percentage of neonatal stays admitted through the ED was highest for Medicaid (1.7 percent) and lowest for private insurance (1.1 percent).
  
  For nonneonatal stays, the average length of stay also was highest for Medicaid (5.0 days) compared with private insurance (4.5 days) and self-pay/no charge (4.3 days). However, average costs and percentage of stays admitted through the ED did not differ as a function of primary expected payer among nonneonatal stays.

Most common reasons for pediatric hospitalizations, 2019
Table 2 presents the 10 most common principal diagnoses for hospital stays among children in 2019.

Table 2. Most common principal diagnoses for hospital stays among children aged 0–17 years by age group, 2019

• Respiratory conditions were among the most common diagnoses for stays by younger children.
  
  Acute bronchitis was the most common reason for inpatient stays among children under 5 years of age, excluding liveborns. Respiratory failure also was among the five most common diagnoses for children under 5 years of age. Pneumonia and asthma were among the top three diagnoses for children aged 1–9 years.



• Mental disorders were among the most common diagnoses for stays by children aged 10 years and older.
  
  The most common reason for inpatient stays among children aged 10 years and older was depressive disorders. Trauma- and stressor-related disorders, suicidal ideation/attempt/intentional self-harm, and other specified and unspecified mood disorders also were among the 10 most common diagnoses for children aged 10 years and older.

State-level characteristics of pediatric hospitalizations, 2019
Table 3 presents the mean length of stay, mean costs, and percentage admitted through the ED among hospital stays for children by the hospital State in 2019. States are ranked from the highest to lowest value on each characteristic.

Table 3. State-level characteristics of hospital stays among children aged 0–17 years, 2019

• The mean length of stay and mean cost of pediatric stays was highest in the District of Columbia and lowest in Wyoming
  
  The District of Columbia had the highest mean length of pediatric inpatient stays in 2019 (5.3 days), whereas Wyoming had the lowest mean length of stay (2.1 days). Similarly, the District of Columbia had the highest mean cost of pediatric stays ($18,600), and Wyoming had the lowest mean cost ($3,100).
  
  States were generally ranked similarly on mean length of stay and mean costs, but there were some exceptions. For example, Washington and California both ranked among the States with the lowest mean length of stay (3.7 and 3.6 days, ranked 42nd and 43rd, respectively), but they ranked among the States with the highest mean costs ($12,800 and $12,300, ranked 4th and 5th, respectively).
  
  The District of Columbia had the highest percentage of pediatric stays admitted through the ED (38.6 percent), and North Dakota had the lowest percentage admitted through the ED (10.1 percent).

References

¹ McDermott KW, Roemer M. Most Frequent Principal Diagnoses for Inpatient Stays in U.S. Hospitals, 2018. HCUP Statistical Brief #277. July 2021. Agency for Healthcare Research and Quality, Rockville, MD. www.hcup-us.ahrq.gov/reports/statbriefs/sb277-Top-Reasons-Hospital-Stays-2018.pdf. Accessed August 25, 2022.
² McDermott KW, Elixhauser A, Sun R. Trends in Hospital Inpatient Stays in the United States, 2005–2014. HCUP Statistical Brief #225. June 2017. Agency for Healthcare Research and Quality, Rockville, MD. www.hcup-us.ahrq.gov/reports/statbriefs/sb225-Inpatient-US-Stays-Trends.pdf. Accessed August 25, 2022.
³ Agency for Healthcare Research and Quality. Healthcare Cost and Utilization Project (HCUP) Fast Stats—National Hospital Utilization & Costs. https://datatools.ahrq.gov/hcup-fast-stats. Accessed August 24, 2022.
⁴ American Hospital Association. TrendWatch Chartbook, 2020. Appendix 1: Supplementary Data Tables, Trends in the Overall Health Care Market. Table 3.4: Outpatient Utilization in Community Hospitals, 1995–2018. www.aha.org/system/files/media/file/2020/10/TrendwatchChartbook-2020-Appendix.pdf. Accessed August 24, 2022.
⁵ Perrin JM, Zimmerman E, Hertz A, Johnson T, Merrill T, Smith D. Pediatric accountable care organizations: insight from early adopters. Pediatrics. 2017;139(2):e20161840.
⁶ Bucholz EM, Toomey SL, Schuster MA. Trends in pediatric hospitalizations and readmissions: 2010–2016. Pediatrics. 2019;143(2):e20181958.

About Statistical Briefs

Healthcare Cost and Utilization Project (HCUP) Statistical Briefs provide basic descriptive statistics on a variety of topics using HCUP administrative healthcare data. Topics include hospital inpatient, ambulatory surgery, and emergency department use and costs, quality of care, access to care, medical conditions, procedures, and patient populations, among other topics. The reports are intended to generate hypotheses that can be further explored in other research; the reports are not designed to answer in-depth research questions using multivariate methods.

Data Source

The estimates in this Statistical Brief are based on data from the HCUP 2019 National Inpatient Sample (NIS) and 2019 State Inpatient Databases (SID). Following the series of reports on children's healthcare in the United States using Agency for Healthcare Research and Quality (AHRQ) databases (available at www.academicpedsjnl.net/content/acap-childrens-health ), this Statistical Brief presents national statistics on pediatric hospitalizations by various patient and visit characteristics using data from the NIS and State-level statistics based on data from the SID. Although it was not used for the children's healthcare reports or this Statistical Brief, AHRQ also produces a Kids' Inpatient Database (KID) every 3 years. The KID includes a sample of discharges for patients aged 20 years or younger at admission. The KID is intended for national estimates only and enables analyses of rare conditions (such as congenital anomalies) and uncommon treatments (such as organ transplantation).

Definitions

Diagnoses, ICD-10-CM, Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses, and Major Diagnostic Categories (MDCs)
The principal diagnosis is that condition established after study to be chiefly responsible for the patient's admission to the hospital. Secondary diagnoses are conditions that coexist at the time of admission that require or affect patient care treatment received or management, or that develop during the inpatient stay. All-listed diagnoses include the principal diagnosis plus the secondary conditions.

ICD-10-CM is the International Classification of Diseases, Tenth Revision, Clinical Modification. There are over 70,000 ICD-10-CM diagnosis codes.

The CCSR aggregates ICD-10-CM diagnosis codes into a manageable number of clinically meaningful categories.^a The CCSR is intended to be used analytically to examine patterns of healthcare in terms of cost, utilization, and outcomes; rank utilization by diagnoses; and risk-adjust by clinical condition. The CCSR capitalizes on the specificity of the ICD-10-CM coding scheme and allows ICD-10-CM codes to be classified in more than one category. Approximately 10 percent of diagnosis codes are associated with more than one CCSR category because the diagnosis code documents either multiple conditions or a condition along with a common symptom or manifestation. For this Statistical Brief, the principal diagnosis code is assigned to a single default CCSR based on clinical coding guidelines, etiology and pathology of diseases, and standards set by other Federal agencies. The assignment of the default CCSR for the principal diagnosis is available starting with version v2020.2 of the software tool. ICD-10-CM coding definitions for each CCSR category presented in this Statistical Brief can be found in the CCSR reference file, available at www.hcup-us.ahrq.gov/toolssoftware/ccsr/ccs_refined.jsp#download. For this Statistical Brief, v2021.2 of the CCSR was used.

MDCs assign ICD-10-CM principal diagnosis codes to 1 of 25 general diagnosis categories. Neonatal stays were defined as those with MDC 15, Newborns and Other Neonates (Perinatal Period).

Types of hospitals included in the HCUP National (Nationwide) Inpatient Sample
The National (Nationwide) Inpatient Sample (NIS) is based on data from community hospitals, which are defined as short-term, non-Federal, general, and other hospitals, excluding hospital units of other institutions (e.g., prisons). The NIS includes obstetrics and gynecology, otolaryngology, orthopedic, cancer, pediatric, public, and academic medical center hospitals. Excluded are long-term care facilities such as rehabilitation, psychiatric, and alcoholism and chemical dependency hospitals. Beginning in 2012, long-term acute care hospitals are also excluded. However, if a patient received long-term care, rehabilitation, or treatment for a psychiatric or chemical dependency condition in a community hospital, the discharge record for that stay will be included in the NIS.

Types of hospitals included in HCUP State Inpatient Databases
This analysis used State Inpatient Databases (SID) limited to data from community hospitals, which are defined as short-term, non-Federal, general, and other hospitals, excluding hospital units of other institutions (e.g., prisons). Community hospitals include obstetrics and gynecology, otolaryngology, orthopedic, cancer, pediatric, public, and academic medical center hospitals. Excluded for this analysis are long-term care facilities such as rehabilitation, psychiatric, and alcoholism and chemical dependency hospitals. However, if a patient received long-term care, rehabilitation, or treatment for a psychiatric or chemical dependency condition in a community hospital, the discharge record for that stay was included in the analysis.

Unit of analysis
The unit of analysis is the hospital discharge (i.e., the hospital stay), not a person or patient. This means that a person who is admitted to the hospital multiple times in 1 year will be counted each time as a separate discharge from the hospital.

Costs and charges
Total hospital charges were converted to costs using HCUP Cost-to-Charge Ratios based on hospital accounting reports from the Centers for Medicare & Medicaid Services (CMS).^b Costs reflect the actual expenses incurred in the production of hospital services, such as wages, supplies, and utility costs; charges represent the amount a hospital billed for the case. For each hospital, a hospital-wide cost-to-charge ratio is used. Hospital charges reflect the amount the hospital billed for the entire hospital stay and do not include professional (physician) fees. For the purposes of this Statistical Brief, costs are reported to the nearest hundred dollars.

How HCUP estimates of costs differ from National Health Expenditure Accounts
There are a number of differences between the costs cited in this Statistical Brief and spending as measured in the National Health Expenditure Accounts (NHEA), which are produced annually by CMS.^c The largest source of difference comes from the HCUP coverage of inpatient treatment only in contrast to the NHEA inclusion of outpatient costs associated with emergency departments (EDs) and other hospital-based outpatient clinics and departments as well. The outpatient portion of hospitals' activities has been growing steadily and may exceed half of all hospital revenue in recent years. On the basis of the American Hospital Association Annual Survey, 2018 outpatient gross revenues (or charges) were about 49 percent of total hospital gross revenues.^d

Smaller sources of differences come from the inclusion in the NHEA of hospitals that are excluded from HCUP. These include Federal hospitals (Department of Defense, Veterans Administration, Indian Health Service, and Department of Justice [prison] hospitals) as well as psychiatric, substance abuse, and long-term care hospitals. A third source of difference lies in the HCUP reliance on billed charges from hospitals to payers, adjusted to provide estimates of costs using hospital-wide cost-to-charge ratios, in contrast to the NHEA measurement of spending or revenue. HCUP costs estimate the amount of money required to produce hospital services, including expenses for wages, salaries, and benefits paid to staff as well as utilities, maintenance, and other similar expenses required to run a hospital. NHEA spending or revenue measures the amount of income received by the hospital for treatment and other services provided, including payments by insurers, patients, or government programs. The difference between revenues and costs includes profit for for-profit hospitals or surpluses for nonprofit hospitals.

Expected payer
To make coding uniform across all HCUP data sources, the primary expected payer for the hospital stay combines detailed categories into general groups:

• Medicare: includes fee-for-service and managed care Medicare
• Medicaid: includes fee-for-service and managed care Medicaid
• Private insurance: includes commercial nongovernmental payers, regardless of the type of plan (e.g., private health maintenance organizations [HMOs], preferred provider organizations [PPOs])
• Self-pay/No charge: includes self-pay, no charge, charity, and no expected payment
  
• Other payers: includes other Federal and local government programs (e.g., TRICARE, CHAMPVA, Indian Health Service, Black Lung, Title V) and Workers' Compensation

Hospital stays that were expected to be billed to the State Children's Health Insurance Program (SCHIP) are included under Medicaid.

For this Statistical Brief, when more than one payer is listed for a hospital discharge, the first-listed payer is used.

Admissions through the ED
Inpatient stays admitted through the ED are identified by the HCUP data element HCUP_ED > 0, which indicates evidence of ED services at the same hospital as the inpatient stay. The assignment of HCUP_ED depends on the reporting of revenue center codes, a Partner-provided flag for ED admissions, or Current Procedural Terminology (CPT^®) procedure codes that identify ED professional services. In data year 2019, the SID for Delaware and New Hampshire include limited information that is needed to identify ED admissions, and therefore, the ED admission rates for these two States may be artificially low.

About HCUP

The Healthcare Cost and Utilization Project (HCUP, pronounced "H-Cup") is a family of healthcare databases and related software tools and products developed through a Federal-State-Industry partnership and sponsored by the Agency for Healthcare Research and Quality (AHRQ). HCUP databases bring together the data collection efforts of State data organizations, hospital associations, and private data organizations (HCUP Partners) and the Federal government to create a national information resource of encounter-level healthcare data. HCUP includes the largest collection of longitudinal hospital care data in the United States, with all-payer, encounter-level information beginning in 1988. These databases enable research on a broad range of health policy issues, including cost and quality of health services, medical practice patterns, access to healthcare programs, and outcomes of treatments at the national, State, and local market levels.

HCUP would not be possible without the contributions of the following data collection Partners from across the United States:

About the NIS

The HCUP National (Nationwide) Inpatient Sample (NIS) is a nationwide database of hospital inpatient stays. The NIS is nationally representative of all community hospitals (i.e., short-term, non-Federal, nonrehabilitation hospitals). The NIS includes all payers. It is drawn from a sampling frame that contains hospitals comprising more than 96 percent of all discharges in the United States. The vast size of the NIS allows the study of topics at the national and regional levels for specific subgroups of patients. In addition, NIS data are standardized across years to facilitate ease of use. Over time, the sampling frame for the NIS has changed; thus, the number of States contributing to the NIS varies from year to year. The NIS is intended for national estimates only; no State-level estimates can be produced. The unweighted sample size for the 2019 NIS is 7,083,805 (weighted, this represents 35,419,023 inpatient stays).

About the SID

The HCUP State Inpatient Databases (SID) are hospital inpatient databases from data organizations participating in HCUP. The SID contain the universe of the inpatient discharge abstracts in the participating HCUP States, translated into a uniform format to facilitate multistate comparisons and analyses. Together, the SID encompass more than 95 percent of all U.S. community hospital discharges. The SID can be used to investigate questions unique to one State, to compare data from two or more States, to conduct market-area variation analyses, and to identify State-specific trends in inpatient care utilization, access, charges, and outcomes.

For More Information

For other information on pediatric hospital stays in the United States, refer to the pediatric HCUP Statistical Briefs topic area located at www.hcup-us.ahrq.gov/reports/statbriefs/sbtopic.jsp.

For additional HCUP statistics, visit:

• HCUP Fast Stats at https://datatools.ahrq.gov/hcup-fast-stats for easy access to the latest HCUP-based statistics for healthcare information topics
• HCUPnet, HCUP's interactive query system, at https://datatools.ahrq.gov/hcupnet
• HCUP Summary Trend Tables at www.hcup-us.ahrq.gov/reports/trendtables/summarytrendtables.jsp for monthly information on hospital utilization

For more information about HCUP, visit www.hcup-us.ahrq.gov/.

For a detailed description of HCUP and more information on the design of the National Inpatient Sample (NIS) and State Inpatient Databases (SID), please refer to the following database documentation:

Agency for Healthcare Research and Quality. Overview of the National (Nationwide) Inpatient Sample (NIS). Healthcare Cost and Utilization Project (HCUP). Rockville, MD: Agency for Healthcare Research and Quality. Updated September 2021. www.hcup-us.ahrq.gov/nisoverview.jsp. Accessed March 9, 2022.

Agency for Healthcare Research and Quality.Overview of the State Inpatient Databases (SID). Healthcare Cost and Utilization Project (HCUP). Rockville, MD: Agency for Healthcare Research and Quality. Updated September 2021. www.hcup-us.ahrq.gov/sidoverview.jsp. Accessed March 9, 2022.

Suggested Citation

Weiss AJ (IBM), Liang L (AHRQ), Martin K (AHRQ). Overview of Hospital Stays Among Children and Adolescents, 2019. HCUP Statistical Brief #299. November 2022. Agency for Healthcare Research and Quality, Rockville, MD. www.hcup-us.ahrq.gov/reports/statbriefs/sb299-Hospital-Stays-Children-2019.pdf.

Acknowledgments

The authors would like to acknowledge the contributions of Marguerite Barrett of M.L. Barrett, Inc., and Minya Sheng of IBM.

***

AHRQ welcomes questions and comments from readers of this publication who are interested in obtaining more information about access, cost, use, financing, and quality of healthcare in the United States. We also invite you to tell us how you are using this Statistical Brief and other HCUP data and tools, and to share suggestions on how HCUP products might be enhanced to further meet your needs. Please email us at hcup@ahrq.gov or send a letter to the address below:

Joel W. Cohen, Ph.D., Director
Center for Financing, Access and Cost Trends
Agency for Healthcare Research and Quality
5600 Fishers Lane
Rockville, MD 20857


This Statistical Brief was posted online on November 29, 2022.


^a Agency for Healthcare Research and Quality. Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP). Agency for Healthcare Research and Quality. Updated February 2022. www.hcup-us.ahrq.gov/toolssoftware/ccsr/dxccsr.jsp. Accessed March 9, 2022.
^b Agency for Healthcare Research and Quality. Cost-to-Charge Ratio Files. Healthcare Cost and Utilization Project (HCUP). Agency for Healthcare Research and Quality. Updated November 2021. www.hcup-us.ahrq.gov/db/state/costtocharge.jsp. Accessed March 9, 2022.
^c For additional information about the NHEA, see Centers for Medicare & Medicaid Services (CMS). National Health Expenditure Data. CMS website. Updated December 1, 2021. www.cms.gov/Research-Statistics-Data-and-Systems/Statistics-Trends-and-Reports/NationalHealthExpendData/index.html?redirect=/NationalHealthExpendData/. Accessed March 9, 2022.
^d American Hospital Association. TrendWatch Chartbook, 2020. Appendix 1: Supplementary Data Tables, Trends in the Overall Health Care Market. Table 4.2: Distribution of Inpatient vs. Outpatient Revenues, 1995–2018. www.aha.org/system/files/media/file/2020/10/TrendwatchChartbook-2020-Appendix.pdf. Accessed March 9, 2022.