Variations in Cause-of-Death Determination for Sudden Unexpected Infant Deaths

To quantify and describe variation in cause-of-death certification of sudden unexpected infant deaths (SUIDs) among US medical examiners and coroners.

From January to November 2014, we conducted a nationally representative survey of US medical examiners and coroners who certify infant deaths. Two-stage unequal probability sampling with replacement was used. Medical examiners and coroners were asked to classify SUIDs based on hypothetical scenarios and to describe the evidence considered and investigative procedures used for cause-of-death determination. Frequencies and weighted percentages were calculated.

Of the 801 surveys mailed, 60% were returned, and 377 were deemed eligible and complete. Medical examiners and coroners classification of infant deaths varied by scenario. For 3 scenarios portraying potential airway obstruction and negative autopsy findings, 61% to 69% classified the death as suffocation/asphyxia. In the last scenario, which portrayed a healthy infant in a safe sleep environment with negative autopsy findings, medical examiners and coroners classified the death as sudden infant death syndrome (38%) and SUID (30%). Reliance on investigative procedures to determine cause varied, but 94% indicated using death scene investigations, 88% full autopsy, 85% toxicology analyses, and 82% medical history review.

US medical examiners and coroners apply variable practices to classify and investigate SUID, and thus, they certify the same deaths differently. This variability influences surveillance and research, impacts true understanding of infant mortality causes, and inhibits our ability to accurately monitor and ultimately prevent future deaths. Findings may inform future strategies for promoting standardized practices for SUID classification.