Research Brief

Geographic, racial imbalances in investigations of sudden unexpected infant death

Grey chair next to a cream crib in a bedroom
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About 3,400 infants die suddenly and unexpectedly in the U.S. every year, but these tragic events do not fall evenly across populations. Deaths are notably higher among Indigenous and Black infants compared with white infants, and rural areas have some of the nation’s highest unexpected death rates.

A new study from the University of Minnesota School of Public Health, published in the Journal of Public Health Management & Practice, examines how disparities based on race, ethnicity and geography play a role in the completeness of sudden infant death investigations.

The researchers analyzed Centers for Disease Control and Prevention data from 3,847 cases between 2015 and 2018. They examined instances of incomplete death investigations — those missing crucial elements such as an autopsy, scene investigation or detailed information about the circumstances of death. The study also identified critical components often missing from investigations such as reenactments and the use of investigative forms and protocols specific to sudden unexpected infant deaths. These are considered essential for a comprehensive understanding of the circumstances surrounding each case. 

The study found:  

  • Incomplete investigations were found in 24% of sudden unexplained infant deaths.
  • Native American and Alaska Native infants were more likely to have incomplete death investigations compared to other racial groups.
  • The odds of having an incomplete death investigation were over 1.5 times higher in rural areas than urban areas. 
  • Death investigations led by law enforcement were less likely to be complete compared to those led by medical examiners. Native Americans and Alaska Natives were more likely than any other group to have an investigation be led by law enforcement. 

“Our work underscores the urgent need for standardized and thorough death investigations across all regions and demographic groups to ensure accurate data collection and effective prevention strategies,” said Naomi Thyden, SPH researcher and lead author. “Involving medical examiners or coroners in all infant death investigations, rather than relying on law enforcement, could significantly improve the completeness of these investigations.” 

This research was supported by a grant from the Health Resources and Services Administration of the U.S. Department of Health and Human Services.

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