Am J Perinatol 2022; 39(11): 1223-1228
DOI: 10.1055/s-0040-1721847
Original Article

Diagnosis-Related Group Weight and Derived Case Mix Index to Assess the Complexity among Twins

Rikizam M. Joya
1   Departments of Neonatology and Pediatrics, West Virginia University School of Medicine, Morgantown, West Virginia
,
Lesley Cottrell
2   Department of Pediatrics, West Virginia University School of Medicine, Morgantown, West Virginia
,
Autumn Kiefer
1   Departments of Neonatology and Pediatrics, West Virginia University School of Medicine, Morgantown, West Virginia
,
Mark J. Polak
2   Department of Pediatrics, West Virginia University School of Medicine, Morgantown, West Virginia
› Author Affiliations

Abstract

Objective Diagnosis-related groups (DRGs) are used to summarize hospital morbidity and mortality. Each DRG has a weight which is important in calculating the case mix index (CMI), a numeric summary of disease complexity in a population of patients. We utilized DRG weight and resultant CMI to compare postnatal outcomes among singletons versus monochorionic and monoamniotic, monochorionic diamniotic, and dichorionic diamniotic twins.

Study Design This single-center and retrospective cohort study evaluated DRGs assigned by the investigators, birth weight, gestational age, length of stay (LOS), NICU admission rate, and mortality in twin births between 2014 and 2016. Twins were analyzed depending on chorionicity and amnionicity. Overall, 3 months of singleton births served as the control. The CMI derived from DRG weights were compared across groups.

Results Twins (n = 288) had lower gestational ages and birth weights and higher mortality, LOS, NICU admission rates and DRG weights/CMI compared with singletons (n = 327; p < 0.001 for each). The LOS was no different between twin subtypes; monochorionic monoamniotic twins had the highest mortality and DRG weight (p < 0.001).

Conclusion DRG weight and CMI values summarize in-hospital complexity and can be a useful tool to evaluate differences in care complexity among groups of patients.

Key Points

  • Using diagnosis-related group and case mix index to assess morbidities.

  • Morbidities of twins are monochorionic-monoamniotic versus monochorionic-diamniotic versus dichorionic-diamniotic twins.

  • Only seven diagnosis-related group in neonatology make it a valuable tool for clinicians.



Publication History

Received: 07 July 2020

Accepted: 16 November 2020

Article published online:
30 December 2020

© 2020. Thieme. All rights reserved.

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