Child mortality at pediatric and other hospitals

Research objective

Regionalization of pediatric hospital care, in which high-risk patients are admitted to regional comprehensive pediatric hospitals while other patients are hospitalized closer to home, has been advocated by the American Academy of Pediatrics and the American College of Critical Care Medicine, among others. The evaluation of hospital quality is complicated by the propensity of more severely-ill patients to receive care at higher-quality hospitals, a phenomenon that leads to the well known problem of case-mix bias. We estimate the relative quality of care provided by pediatric hospitals using an instrumental variables approach that mitigates these biases.

Study design

Child mortality rates were compared at pediatric hospitals and other hospitals. Patient characteristics and diagnosis-related groups (DRGs) were used to control for observable case-mix variation. To account for unobservable case-mix differences, we instrumented for hospital choice using the differential distance from each patient's residence to the nearest pediatric hospital, relative to the nearest hospital.

Population studied

All children age 14 years and younger hospitalized in New York State during the period 1996-2002, excluding neonates. Additional analyses were performed for a subgroup of children with an elevated risk of death. Our estimation samples contained 903,388 and 355,571 children, respectively.

Principal findings

The overall child mortality rate was 3.5 deaths / 1000 hospitalizations. Analysis controlling only for patient characteristics indicates that pediatric hospitals have an excess mortality rate of 7.7 / 1000 hospitalizations. Adding DRGs to the set of control variables reduced the excess mortality at pediatric hospitals to 3.0 / 1000. However, when the instrumental variables estimator was employed, the mortality rate at pediatric hospitals was lower than at other hospitals by 4.7 deaths / 1000. For high-risk patients, the mortality reduction at pediatric hospitals was three times larger: 14 deaths / 1000.

Conclusions

Our estimates provide evidence that pediatric hospitals treat sicker patients than non-pediatric hospitals, that part of the difference in illness severity is unobservable, and that after adjusting for case-mix differences, pediatric hospitals provide higher quality care than other hospitals, especially for children whose clinical characteristics heighten their risk of death. These findings support a role for regionalization of hospital services for children and suggest that regulatory interventions should balance the efficiency gains from competition in hospital markets with the superior clinical outcomes that arise when patients have appropriate access to comprehensive pediatric hospitals.