OBJECTIVE: Despite the documented utility of regionalized systems of pediatric specialty care, little is known about the actual use of such systems in total populations of chronically ill children. The objective of this study was to evaluate variations and trends in regional patterns of specialty care hospitalization for children with chronic illness in California.
METHODS: Using California's Office of Statewide Health Planning and Development unmasked discharge data set between 1999 and 2007, we performed a retrospective, total-population analysis of variations in specialty care hospitalization for children with chronic illness in California. The main outcome measure was the use of pediatric specialty care centers for hospitalization of children with a chronic condition in California.
RESULTS: Analysis of 2 170 102 pediatric discharges revealed that 41% had a chronic condition, and 44% of these were discharged from specialty care centers. Specialty care hospitalization varied by county and type of condition. Multivariate analyses associated increased specialty care center use with public insurance and high pediatric specialty care bed supply. Decreased use of regionalized care was seen for adolescent patients, black, non-Hispanic children, and children who resided in zip codes of low income or were located farther from a regional center of care.
CONCLUSIONS: Significant variation exists in specialty care hospitalization among chronically ill children in California. These findings suggest a need for greater scrutiny of clinical practices and child health policies that shape patterns of hospitalization of children with serious chronic disease.
WHAT'S KNOWN ON THIS SUBJECT:
Regionalized specialty services have become a central component of modern pediatric care. Evidence suggests that outcomes are improved when children with serious or rare conditions have timely access to clinicians and facilities with special expertise in caring for these children.
WHAT THIS STUDY ADDS:
There is little information regarding recent trends in the use of regionalized specialty care systems in total populations of children. This study documents major variations in the use of specialty care facilities for hospitalizing children with chronic illness in California.
Regionalized specialty services have become a central component of modern pediatric care. Evidence from a variety of studies has suggested that outcomes are improved when children with serious or relatively rare conditions have timely access to clinicians and facilities with special expertise in caring for these children. In response, neonatal intensive care,1 pediatric intensive care,2,3 pediatric trauma care,4,5 and clinical services for a variety of chronic conditions, including cystic fibrosis,6 sickle cell disease,7 cancer,8 and congenital heart defects,9 have been organized into regional referral systems that are designed to provide specialty care for consultation and, when necessary, hospitalization.
Although these regionalized systems have become an integral part of the standard of care for children with serious chronic disease, formal requirements for referral vary considerably by state and, increasingly, by health insurance coverage plan. In California, children who have a serious chronic illness and are eligible for Medicaid or other public insurance programs are largely covered by the California Children's Services (CCS) program, which provides care coordination services and insurance coverage for care that is delivered at facilities that meet criteria for designation as a pediatric specialty care center; however, these formal referral criteria do not apply to children who are not enrolled in the CCS program. Moreover, specialty care referral systems in California and in other parts of the country are increasingly confronted by growing instability in health care delivery and financing structures,10 as well as the growing contribution of chronic disease to childhood morbidity, mortality, and health care costs.11,–,17
Despite the growing importance and potential vulnerability of regionalized specialty care systems for children with chronic disorders, there is a striking paucity of information regarding recent trends in the actual use of such systems in total populations of children. To address this issue, we examined hospitalization patterns for all children with chronic illness in California between 1999 and 2007. Of special concern was the extent to which significant variations in specialty care hospitalization patterns emerged during this period and how these patterns reflect the growing influence of nonclinical determinants, including poverty, race/ethnicity, insurance coverage, geographic location, and hospital bed supply.
A retrospective analysis of pediatric hospitalizations for children aged 0 to 18 years at the time of admission in California during the period 1999 to 2007 was performed using the Unmasked Patient Discharge Database from the Office of Statewide Health Planning and Development (OSHPD). This data set contains information on all discharges from nonfederal acute care hospitals, including for the 1999–2007 period, the principal diagnosis, and up to 24 secondary diagnoses. Payer status was categorized as public insurance (Medicare, Medi-Cal [California's Medicaid program], county indigent programs, State Children's Health Insurance Program, and Title V–supported CCS), private insurance, and other (worker's compensation, self-pay and other payer).
Inclusion and Exclusion Criteria
There were 3 951 549 pediatric discharges during the study period. The analysis excluded newborn admissions (diagnosis-related group 391 or with admission source “newborn” or admission type “infant,” <24 hours old [excluded 1 206 389]), childbirth (major diagnostic group 14, pregnancy, childbirth, and the puerperium [excluded 332 686]), trauma (excluded 200 110), or non-California residents (excluded 42 262). This generated a total of 2 170 102 discharges that met inclusion criteria.
Chronic Condition Identification
We defined chronic conditions categorically on the basis of discharge diagnosis as those expected to be associated with elevated or unusual needs for health care or educational services18 of a duration of ≥3 months. This categorical diagnostic approach13,16 was used to generate a list of chronic conditions, which were reviewed by subspecialist consultants and grouped into 10 diagnostic groups. The use of the criterion of 3-month duration was based on previous suggestions19 and use in federal data sets.20 Each discharge was counted only once with a chronic designation when any of the coded chronic diagnoses were associated with the admission—approximately half designated by a primary diagnosis and half by a secondary diagnosis. For a detailed description of coding procedures, see the Appendix.
Specialty Care Center Identification
The identification of a specialty care center was based on the CCS designation as a site with the highest level of pediatric intensive care. This designation was associated with a high degree of clustering of CCS subspecialty designations and the presence of specially trained PICU staff; high-level respiratory support, monitoring, and other technologies; and high-volume treatment experience for patients with a variety of chronic conditions. During the study period, the same 20 hospitals in California had such a CCS designation,21 including 7 children's hospitals.22
Bed Days and Transfers
Total bed days represent the number of discharges with a particular length of stay (LOS) multiplied by that LOS, then summed over all bed days. The OSHPD data set codes admissions of <24 hours' duration as having an LOS of 1 day. Such admissions accounted for ∼3% of all chronic illness admissions. We examined transfers from non–specialty care facilities to other acute care hospitals, although the precise identity of the receiving hospital cannot be discerned from the OSHPD hospital discharge data set.
Hospital Bed Supply Data
Pediatric bed supply was derived from the 2005 American Hospital Association database and OSHPD databases, calculated as total pediatric beds per 100 000 pediatric population aged 0 to 17 years per county. We grouped counties into 5 referral regions on the basis of the clustering of facilities that accounted for the highest portion of chronic illness admissions in each county: the Bay Area, Sacramento, Madera, Los Angeles, and San Diego regions. Bed supply was assigned as low (<20 specialty care beds per 100 000 population) or high (>20 specialty care beds per 100 000 population) category, a designation that fell approximately midway in the distribution of bed capacities.
Population, Income, and Geographic Proximity
Childhood population data were obtained from the US Census Bureau for the census year of 2000.23 Median household income for zip codes were derived from Claritas, Inc, databases24 and categorized on the basis of the federal poverty level (FPL) for 2004 ($18 850 for a family of 4).25 Proximity of patient residence to specialty care hospital was calculated as the shortest geographic distance between the midpoint of the patient's zip code and the midpoint of the admission hospital's zip code.26,27
Endotracheal Intubation and Mortality
It was not possible to assess clinical severity on admission or compare case fatality rates for different hospital types. The OSHPD data set does not provide detailed information on clinical severity, and the number of deaths that occurred in non–specialty care hospitals was relatively low for any given condition. However, we did examine 2 situations that could serve as sentinel indicators of inadequate referral to a specialty center: admissions to a non–specialty care facility involving endotracheal intubation or those ending in death with an LOS of >2 days.
We used logistic regression to examine the influence of patient characteristics and other factors on the probability of discharge from a specialty care facility. The fit of the logistic regression model was assessed by the Hosmer-Lemeshow goodness-of-fit test. All analyses were performed by using SAS 9.1 (SAS Institute Inc, Cary, NC) statistical software. The percentage changes between study years were calculated by using the formula [(year A value/year B value) − 1] × 100, where year A is the later comparison year and year B is the earlier comparison year. We present odds ratios and 95% confidence intervals, and a value of P < .05 was deemed statistically significant. When multiple comparisons were made, we applied Bonferroni correction. We used 2-sample tests for equality of proportions to test the difference between 2 proportions using R software.
The Institutional Review Board at Stanford University and the State of California Committee for the Protection of Human Subjects reviewed and approved this study.
There were 3 951 549 pediatric discharges in California between 1999 and 2007, and 2 170 102 met inclusion criteria. Of these, 41% had a chronic condition diagnosis; for this subset, 44% were cared for in a specialty care center (Table 1). Overall, the number of pediatric bed days in California declined whereas those that were associated with the care of children with chronic illnesses rose during the study period. Both the percentage of discharges and bed days associated with chronic conditions were higher among older children. The total number of pediatric beds fell by 19% during the study period; however, pediatric beds in the designated specialty care facilities fell by only 2% during this same period.
During the study period, the total number of discharges from specialty care hospitals rose by ∼12% and bed days by 20%, whereas the figures for non–specialty care facilities fell by 16% and 15%, respectively (Table 2). This produced a growing concentration of pediatric hospitalizations in specialty care centers: with by 2007, ∼44% of total pediatric admissions and 51% of total pediatric bed days occurred in 4% of California hospitals designated as specialty care facilities for children. Specialty care hospital bed days that were associated with chronic illness rose by 27%, whereas that for non–chronically ill rose 9% (P < .001). Although transfers from non–specialty care hospitals to other acute care facilities rose during the study period, they accounted for <10% of discharges in each of the years of study.
Variation in Chronic Illness Hospitalizations
There was considerable geographic variation in the percentage of pediatric hospitalizations that occurred in specialty care facilities (Fig 1). Specialty care centers were concentrated in the most populous metropolitan areas, and although residing in a county with a specialty care center increased the likelihood of being admitted to such a facility, there remained considerable variation in hospitalization patterns. The most populous county, Los Angeles County, had a percentage of only 60%, and there was considerable variation among counties in the northern part of the state. There was also substantial variability in the likelihood of specialty care hospitalization for different chronic conditions, which are presented in Table 3. Approximately 23% of discharges had >1 chronic diagnosis; however, all but 4% fell within the same broad diagnostic grouping. Asthma (International Classification of Diseases, Ninth Revision code 493) and mental health conditions were characterized by relatively low specialty care hospitalization. When asthma and mental health conditions were excluded, the percentage of chronic illness hospitalizations that occurred in a specialty care center for 2007 rose from 48% to 59%.
Bivariate and Multivariate Analyses
For all chronic illness discharges, including asthma and mental health conditions, the unadjusted, bivariate analyses suggested that adolescents, white non-Hispanic children, those who resided in zip codes with 2 and 2-4 times the FPL, girls, further residential proximity, lower supply of pediatric specialty care beds, and children with private insurance relative to publicly insured children were less likely to be discharged from a specialty care facility (Table 4).
Asthma is a chronic condition with both a high prevalence and a variable requirement for specialty care hospitalization. In addition, hospitalization for mental health conditions in California were heavily influenced by the presence of specialized mental health facilities that fall outside the CCS designation system. Models that both included and excluded asthma and mental health conditions suggested that the strong relationships between age, public payer, close hospital proximity, and high pediatric bed supply and specialty care referral remained highly significant for both sets of models. There was considerable variation among the specialty care hospitals in the proportion of patients with public insurance (range: 28.5%–96.1%), which reflected in part the demographic characteristics of the contiguous areas; however, once payer status and proximity variables were entered into the models, the likelihood that black non-Hispanic or poorer children would be hospitalized in a specialty care center fell significantly below that of their white or wealthier counterparts, respectively.
The increased likelihood of specialty care hospitalization among publicly insured children resulted in a significant rise during the study period in the portion of all discharges from specialty care hospitals that are insured by public programs such as CCS, Medicaid, and the State Children's Health Insurance Program. Figure 2 depicts the absolute and relative changes in payer status by hospital type between 1999 and 2007.
Endotracheal Intubation and Mortality
During the study period, specialty care hospitals accounted for a growing portion of all chronic illness admissions in which endotracheal intubation or death occurred among pediatric hospitalizations in California with an LOS of >2 days. This trend was most pronounced for in-hospital deaths, with ∼72% occurring in specialty care facilities in 1999 and almost 80% in 2007 (P < .01). For the entire study period, ∼1 in 5 admissions that were associated with endotracheal intubation and 1 in 6 deaths among hospitalized children with lengths of stay of >2 days occurred in non–specialty care facilities.
The findings of this total-population study suggest that although a major portion of chronically ill children who require hospitalization in California are cared for in specialty care facilities, considerable variation exists in the use of these hospitals. This variation in specialty care hospital use was related to the specific clinical condition, the age of the child, and the proximity of the child's residence to a specialty care facility. Of particular note was the finding that children who were covered by private insurance were significantly less likely to be cared for in a specialty care facility than their publicly insured counterparts. This resulted in a growing concentration of publicly insured, chronically ill children in specialty care hospitals.
Although children who resided closer to a specialty care hospital were more likely to be hospitalized in that facility, there was considerable variation in specialty care hospital use even among the more densely populated counties. The highest use of specialty care facilities was observed for the neighboring Madera and Fresno counties, a region served by 1 large pediatric specialty center and 13 other pediatric inpatient settings. In contrast, Los Angeles County, with 7 pediatric specialty care centers and 97 other pediatric inpatient sites, admitted only 60% of children with chronic illness to pediatric specialty centers. This may have been related to the availability of non–specialty care facilities and a relatively low supply of specialty care beds in Los Angeles County.28,29
The variation in specialty care hospitalization was attributable in part to the significantly reduced use of such facilities by children with private insurance. Although the precise reasons for this finding are likely complex,30 the possibility that large health maintenance organizations or other hospital contracting arrangements could be contributing to this trend deserves additional exploration. In addition, the availability and distribution of pediatric subspecialists across the state could help to explain the observed variations in specialty care hospital use. Moreover, the variation in the specialty care bed supply could be generating a relative saturation of specialty care capacity in certain areas, particularly in light of the reduction of pediatric beds in non–specialty facilities during the study period. These issues deserve greater analytic scrutiny and suggest that a more comprehensive approach to regionalized pediatric specialty care in the state may be warranted.
Despite considerable instability in the financial base of publicly financed health care in California,31 the hospitalization patterns for some of the most potentially serious conditions, including congenital heart disease and cancer, trended toward greater concentration of hospital care in specialty care facilities. This suggests that the state structures that are designed to ensure access to specialty care services for low-income children who have a serious chronic illness, particularly the CCS program, seemed to be successful in providing stable access to specialty care facilities for these highly vulnerable children. More broadly, the differences in specialty care hospitalization patterns between privately and publicly insured children have made specialty care facilities increasingly vulnerable to the reimbursement policies of public insurance programs. This finding is particularly worrisome given current pressures to reduce hospital payments for publicly insured children32,33 and the long-standing inadequacy of reimbursement for children with complex conditions.14
This study did not assess differences in medical outcomes associated with specialty care hospital use and therefore cannot assess directly the quality of care provided in any individual facility; however, the wide consensus that seriously ill children should receive care in a facility with specialized expertise34,–,36 provides a useful expectation of system functioning against which the hospitalization patterns in this study should be gauged. In this context, the findings that a large number of children who required endotracheal intubation and that 1 in 6 deaths among children who were hospitalized with a chronic condition occurred in non–specialty care hospitals after 2 days after admission are worrisome. Although these cases may include planned admissions for palliative care close to home or reflect a lack of capacity in regional specialty care centers, that seriously ill children received extended care in a non–specialty care setting deserves purposeful examination and, if necessary, a programmatic response.
The variations documented by this study also underscore the dynamic nature of regionalized systems and the need to assess referral patterns for some generally less serious, high-prevalence chronic conditions, particularly given that some nondesignated hospitals could possess selected arenas of clinical expertise that are not recognized by the official CCS mechanisms. Such insights might also permit overburdened specialty care centers to focus their expertise and resources on children who would most benefit from such care. The finding that adolescents were much less likely to be hospitalized in a specialty care facility should also be examined, particularly in relation to the relative utility of pediatric and adult hospital services. The development of population-based clinical data sets could facilitate the more refined examination of clinical referral for children with chronic illness, including comparative effectiveness analyses, which could help guide more efficient evidence-based models of high-quality chronic care management.37
The findings of this study should be interpreted with some caution. Although the general accuracy of the OSHPD hospital discharge data set has been confirmed for adults,38,39 the accuracy of diagnostic codes and patient characteristics for children has not been assessed. Our analyses did not assess the influence of acute or chronic comorbidities on specialty care hospitalization but rather was designed conservatively to capture all hospitalized children with a chronic condition. Some caution should also be used in extending the findings of this study to other states, because large geographic areas of California are without a specialty care facility, which may generate referral patterns that are different from states in which specialty care centers are more evenly distributed. Nevertheless, the findings of this study are of national concern in that 1 in 8 children in the United States lives in California and that the financial and capacity pressures on regionalized specialty care systems documented in this study likely exist in many other states; therefore, although the heterogeneity of needs and health system functioning in the United States must be recognized, the findings of this study serve to underscore the requirement for all jurisdictions to monitor the well-being of regionalized systems of pediatric care and address observed or potential threats to the equitable provision of appropriate levels of care in a highly dynamic health care environment.
This total-population study suggests that efforts to improve the quality of care that is provided children with chronic illness should include the assessment of regional systems of specialty care referral and hospitalization. Moreover, the findings of this study suggest that regionalized systems of care for children may be increasingly vulnerable to referral practices in private health care plans as well as the adequacy of public insurance programs. The challenge lies in creating the patterns of practice and elements of health policy that will strengthen the appropriate use of regionalized systems and ensure that this essential component of modern pediatric care be provided equitably to all children in need.
APPENDIX: CHRONIC CONDITION CODING PROCEDURES
A total of 9461 different diagnostic codes were associated with the studied discharges, although the vast majority of these codes occurred only rarely. Each diagnostic code was ranked by the frequency of occurrence and then reviewed by the study investigators to determine whether it met the definition of a chronic condition described in the text. This process continued until ∼91.6% of all diagnoses were categorized as either chronic or nonchronic in character. The remaining diagnostic codes each accounted for <0.03% of all diagnoses and were not reviewed. The codes that were categorized as a chronic condition were then reviewed and refined by groups of consulting pediatric subspecialists. Each chronic condition was assigned to 1 of 10 broad diagnostic groupings (renal, hematology/oncology, cardiovascular, gastrointestinal, neurology/genetics, endocrine, immunology/infectious disease/rheumatology, pulmonary, mental health, and other). The codes for the major chronic conditions are presented in Table 5.
This project was supported by a grant from the Lucile Packard Foundation for Children's Health awarded to Dr Wise.
Dr Chamberlain had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
- Accepted January 25, 2010.
- Address correspondence to Lisa J. Chamberlain, MD, MPH, Department of Pediatrics, Stanford University School of Medicine, 770 Welch Rd. 100, Palo Alto, CA 94304. E-mail:
FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose.
- CCS =
- California Children's Services •
- OSHPD =
- Office of Statewide Health Planning and Development •
- LOS =
- length of stay •
- FPL =
- federal poverty level
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Going Outside Is Easier Said Than Done: Children seem to be spending more and more time indoors and less and less outdoors, according to an article in The Wall Street Journal (Associated Press, April 14, 2010). According to Susan Linn, director of the Campaign for a Commercial-Free Childhood, “There is a growing movement of parents who are concerned and are trying to figure out how to get their kids outside.” The problem appears to be the pull that screens and phones have on our children and teenagers, with teens spending almost 11 hours a day tied up with various types of media or social networking online, according to a January report from the Kaiser family Foundation. These high rates of media exposure are highly associated with childhood obesity. The article suggests that parents should decree that every hour of screen time be balanced by at least one hour of outdoor time—not a bad suggestion for us to recommend to our patients and families.
Noted by JFL, MD
- Copyright © 2010 by the American Academy of Pediatrics