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Disparities in delivery hospital risk-adjusted outcomes for very low birthweight infants: the role of NICU volume and level of care

Journal of Perinatology (2025)Cite this article

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Abstract

Objective

Describe racial and ethnic differences in delivery hospital NICU risk-adjusted mortality and morbidity rates (RAMMR), stratified by volume and level of care.

Study design

Cross-sectional analysis of all very low birthweight (<1500 g; VLBW) infants born in Michigan, Oregon, and South Carolina between 2010 and 2020 and Pennsylvania between 2010 and 2018 (n = 37,784). Lorenz concentration curves and indices were used to describe differences in NICU RAMMR by race and ethnicity. Analysis was performed for overall cohort; high-level, high-volume NICUs; and low-level and/or low-volume NICUs.

Result

Despite being most frequently born at high-level, high-volume centers, Non-Hispanic Black (NHB) neonates were overrepresented at hospitals with high RAMMR and all other groups were overrepresented at hospitals with lower RAMMR. Differences were most pronounced in the low-level and/or low-volume cohort.

Conclusion

NHB VLBW infants born at hospitals with low-level and/or low-volume NICUs are disproportionately exposed to adverse outcomes and must be the focus of future policy interventions.

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Fig. 1: Exclusion criteria.
Fig. 2: Delivery hospital distribution.
Fig. 3: Concentration indices and concentration curves depicting racial and ethnic differences in delivery hospital RAMMR.

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Data availability

Data were obtained through specific data use agreements with the governments of the states included in this study. Individuals seeking to complete work utilizing these datasets must reach out to each state to obtain direct approvals and data access.

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Acknowledgements

Authors: Dr. Gia Yannekis was supported by AHRQ grant number T32HS000063 as part of the Harvard-wide Pediatric Health Services Research Fellowship Program.

Additional Contributions: Joshua Radack, MS contributed significantly to NICU level assignment verification. Davene Wright, PhD served as Gia Yannekis’s mentor through the Harvard-Wide Pediatric Health Services Research Fellowship and provided support in project development and editing.

Michigan: The data used in this manuscript was acquired from the Michigan Department of Health and Human Services (MDHHS). The contents of this document including data analysis, interpretation or conclusions are solely the responsibility of the authors and do not represent the official views of MDHHS.

Oregon: Oregon Health Authority. Oregon Hospital Discharge Data (2010-2020). Oregon Health Authority Hospital Reporting Program. Portland, OR; 2023.

Pennsylvania: The Pennsylvania Health Care Cost Containment Council (PHC4) is an independent state agency responsible for addressing the problem of escalating health costs, ensuring the quality of health care, and increasing access to health care for all citizens regardless of ability to pay. PHC4 has provided data to this entity in an effort to further PHC4’s mission of educating the public and containing health care costs in Pennsylvania. PHC4, its agents, and staff, have made no representation, guarantee, or warranty, express or implied, that the data – financial, patient, payor, and physician specific information – provided to this entity, are errorfree, or that the use of the data will avoid differences of opinion or interpretation. This analysis was not prepared by PHC4. This analysis was done by the aforementioned authors, based in the Lorch Lab at Children’s Hospital of Philadelphia, as well as at Beth Israel Deaconess Medical Center and Boston Children’s Hospital. PHC4, its agents and staff, bear no responsibility or liability for the results of the analysis, which are solely the opinion of this entity.

South Carolina: This information is from the records of the Revenue and Fiscal Affairs Office, Health and Demographics Section, South Carolina. Our authorization to release this information does not imply endorsement of this study or its findings by either the revenue and fiscal affairs office or the data oversight council.

Funding

Funding for this study was provided by Eunice Kennedy Shriver National Institute of Child Health and Human Development R01HD099197 and R01HD084819.

Author information

Authors and Affiliations

  1. Department of Neonatology, Beth Israel Deaconess Medical Center, Boston, MA, USA

    Gia Yannekis & Sarah N. Kunz

  2. Division of Newborn Medicine, Harvard Medical School, Boston, MA, USA

    Gia Yannekis & Sarah N. Kunz

  3. Division of Neonatology, Children’s Hospital of Philadelphia, Philadelphia, PA, USA

    Molly Passarella, Brielle Formanowski & Scott A. Lorch

  4. Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA

    Scott A. Lorch

  5. Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, PA, USA

    Scott A. Lorch

Authors
  1. Gia Yannekis
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  2. Sarah N. Kunz
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  5. Scott A. Lorch
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Contributions

Dr. Scott Lorch developed the dataset for this project. Drs. Gia Yannekis, Sarah Kunz, and Scott Lorch all contributed to idea development, project design, data analysis, and manuscript writing and editing. Molly Passarella and Brielle Formanowski cleaned and prepared data and assisted with data analysis and with editing of the final product.

Corresponding author

Correspondence to Gia Yannekis.

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Competing interests

The authors declare no competing interests.

Ethics approval and consent to participate

This study was determined to be Non-Human Subjects Research by the Institutional Review Boards of the Children’s Hospital of Philadelphia (IRB 20-017453), Beth Israel Deaconess Medical Center (2023D000917), and Boston Children’s Hospital (IRB-P00046692). All methods were performed in accordance with the relevant guidelines and regulations.

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Yannekis, G., Kunz, S.N., Passarella, M. et al. Disparities in delivery hospital risk-adjusted outcomes for very low birthweight infants: the role of NICU volume and level of care. J Perinatol (2025). https://doi.org/10.1038/s41372-025-02434-7

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  • DOI: https://doi.org/10.1038/s41372-025-02434-7

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