Am J Perinatol 2019; 36(11): 1106-1114
DOI: 10.1055/s-0039-1681097
SMFM Fellowship Series Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

A Validation Study of Maternal Early Warning Systems: A Retrospective Cohort Study

Elizabeth A. Blumenthal
1   Department of Obstetrics and Gynecology, University of California, Irvine, Orange, California
,
Nina Hooshvar
1   Department of Obstetrics and Gynecology, University of California, Irvine, Orange, California
,
Miriam McQuade
1   Department of Obstetrics and Gynecology, University of California, Irvine, Orange, California
,
Jennifer McNulty
2   Department of Obstetrics and Gynecology, Long Beach Memorial Miller Children's and Women's Hospital, Long Beach, California
› Author Affiliations
Funding The Memorial Care Foundation provided funding for the study including statistical analysis of data as well as travel for presentation of the study at the Society of Maternal Fetal Medicine meeting. Statistical design was supported by grant UL1 TR001414 from the National Center for Advancing Translational Sciences, National Institutes of Health (NIH), through the Biostatistics, Epidemiology and Research Design Unit. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
Further Information

Publication History

03 October 2018

31 January 2019

Publication Date:
11 March 2019 (online)

Abstract

Objective We compare validation characteristics of four early warning systems for maternal morbidity.

Study Design We used a retrospective cohort of severe maternal morbidity cases between January 2016 and December 2016 compared with a cohort of controls. We determined if the modified early obstetric warning score (MEOWS), maternal early recognition criteria (MERC), modified early warning system (MEWS), or maternal early warning trigger (MEWT) would have alerted. We developed criteria to determine which of these alerts was considered clinically “relevant.”

Results We reviewed 79 morbidity cases and 123 controls. MEOWS and MERC were more sensitive than MEWS or MEWT (67.1 and 67.1% vs. 19% and 40.5%, p < 0.001); however, MEWT and MEWS were more specific (88.6% MEWT and 93.5% MEWS vs. 51.2% MEOWS and 60.2% MERC, p < 0.001). In the control population, 70% of MEWT alerts still appeared “relevant” to the clinical scenario in contrast to the MEOWS (32%) or MERC systems (31%).

Conclusion There are limited comparative data regarding how early warning systems perform in an American population for maternal morbidity. None of the systems performs with high sensitivity and specificity. High-volume, high-acuity units may decide that the lower sensitivity of the MEWT is relatively acceptable when considering the high false trigger rate of the other more sensitive systems. In addition, triggers in the MEWT system were more likely to be clinically relevant even in cases that did not have severe morbidity.

Supplementary Material

 
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