Correction: Inferring school district learning modalities during the COVID-19 pandemic with a hidden Markov model.

[This corrects the article DOI: 10.1371/journal.pone.0292354.].

Characteristics of Sudden Unexpected Infant Deaths on Shared and Nonshared Sleep Surfaces.

OBJECTIVES: Describe characteristics of sudden unexpected infant deaths (SUID) occurring on shared or nonshared sleep surfaces. METHODS: We examined SUID among residents of 23 US jurisdictions who died during 2011 to 2020. We calculated frequencies and percentages of demographic, sleep environment, and other characteristics by sleep surface sharing status and reported differences of at least 5% between surface sharing and nonsharing infants. RESULTS: Of 7595 SUID cases, 59.5% were sleep surface sharing when they died. Compared with nonsharing infants, sharing infants were more often aged 0 to 3 months, non-Hispanic Black, publicly insured, found supine, found in an adult bed or chair/couch, had a higher number of unsafe sleep factors present, were exposed to maternal cigarette smoking prenatally, were supervised by a parent at the time of death, or had a supervisor who was impaired by drugs or alcohol at the time of death. At least 76% of all SUID had multiple unsafe sleep factors present. Among surface-sharing SUID, most were sharing with adults only (68.2%), in an adult bed (75.9%), and with 1 other person (51.6%). Surface sharing was more common among multiples than singletons. CONCLUSIONS: Among SUID, surface sharing and nonsharing infants varied by age at death, race and ethnicity, insurance type, presence of unsafe sleep factors, prenatal smoke exposure, and supervisor impairment. Most SUID, regardless of sleep location, had multiple unsafe sleep factors present, demonstrating the need for comprehensive safe sleep counseling for every family at every encounter.

Neighborhood Deprivation and Privilege: an Examination of Racialized-Economic Segregation and Preterm Birth, Florida 2019.

The Black-White disparity in preterm birth persists and is not fully explained by individual-level social, behavioral, or clinical risk factors. Consequently, there is increasing emphasis on understanding the role of structural and area-level factors. Racialized-economic segregation measured as the index of concentration at the extremes (ICE) simultaneously captures extremes of deprivation and privilege. Our objective was to examine associations between preterm birth (PTB) and the index of concentration at the extremes (ICE). In this cross-sectional study, we analyzed 193,957 Florida birth records from 2019 linked to 2015-2019 census tract data from the American Community Survey. We assessed PTB (< 37 weeks gestation) by subtypes: (1) early (< 34 weeks) and late (34-36 weeks) and (2) spontaneous and indicated (i.e., provider-initiated) deliveries. We calculated adjusted odds ratios (aOR) and 95% confidence intervals (CI) for three ICE measures: (1) ICE_INC: income, (2) INC_INC + WB: income + race/ethnicity (non-Hispanic White vs. Black), and (3) INC_INC + WH: income + race/ethnicity (non-Hispanic White vs. Hispanic). Results. For ICE_INC and INC_INC + WB, aORs for residing in the worst-off vs. best-off areas were 1.25 (95% CI: 1.12, 1.46) and 1.21 (95% CI: 1.07, 1.37) for early PTB, respectively, and 1.16 (95% CI: 1.05, 1.28) to 1.22 (95% CI: 1.12, 1.34) for indicated PTB. In conclusion, deprivation captured by ICE was associated with increased odds of early or indicated PTB. Eliminating PTB disparities may require a multifaceted approach that includes addressing the interplay between income and race/ethnicity in residential areas.

Inferring school district learning modalities during the COVID-19 pandemic with a hidden Markov model.

During the COVID-19 pandemic, many public schools across the United States shifted from fully in-person learning to alternative learning modalities such as hybrid and fully remote learning. In this study, data from 14,688 unique school districts from August 2020 to June 2021 were collected to track changes in the proportion of schools offering fully in-person, hybrid and fully remote learning over time. These data were provided by Burbio, MCH Strategic Data, the American Enterprise Institute's Return to Learn Tracker and individual state dashboards. Because the modalities reported by these sources were incomplete and occasionally misaligned, a model was needed to combine and deconflict these data to provide a more comprehensive description of modalities nationwide. A hidden Markov model (HMM) was used to infer the most likely learning modality for each district on a weekly basis. This method yielded higher spatiotemporal coverage than any individual data source and higher agreement with three of the four data sources than any other single source. The model output revealed that the percentage of districts offering fully in-person learning rose from 40.3% in September 2020 to 54.7% in June of 2021 with increases across 45 states and in both urban and rural districts. This type of probabilistic model can serve as a tool for fusion of incomplete and contradictory data sources in order to obtain more reliable data in support of public health surveillance and research efforts.

Associations Between Breastfeeding and Post-perinatal Infant Deaths in the U.S.

INTRODUCTION: Initiation of breastfeeding has been associated with reduced post-perinatal infant mortality. Although most states have initiatives to protect, promote, and support breastfeeding, no analysis of the association between breastfeeding and infant mortality has been conducted at the state and regional levels. To understand the associations between breastfeeding and post-perinatal infant mortality, the initiation of breastfeeding with post-perinatal infant mortality was analyzed by geographic region and individual states within each region. METHODS: This study was a prospective cohort analysis linking U.S. national birth and post-perinatal infant death data for nearly 10 million infants born in 2016-2018, who were then followed for one year after birth and analyzed in 2021-2022. RESULTS: A total of 9,711,567 live births and 20,632 post-perinatal infant deaths from 48 states and the District of Columbia were included in the analysis. The overall AOR and 95% CIs for breastfeeding initiation with post-perinatal infant mortality was 0.67 (0.65, 0.69, p<0.0001) for days 7-364. All seven U.S. geographic regions had significant reductions in postperinatal infant deaths associated with breastfeeding initiation; Mid-Atlantic and Northeast regions had the largest reductions with AOR of 0.56 (95% CI=0.51, 0.61, p<0.001 and 0.50, 0.63, p<0.001, respectively), whereas the Southeast had the smallest reduction with AOR of 0.79 (95% CI=0.75, 0.84, p<0.001). Statistically significant results were noted for 35 individual states for reduction in total post-perinatal infant deaths. CONCLUSIONS: Although regional and state variation in the magnitude of the association between breastfeeding and infant mortality exists, the consistency of reduced risk, together with existing literature, suggests that breastfeeding promotion and support may be a strategy to reduce infant mortality in the U.S.

Sudden Unexpected Infant Deaths: 2015-2020.

OBJECTIVE: Although the US infant mortality rate reached a record low in 2020, the sudden infant death syndrome (SIDS) rate increased from 2019. To understand if the increase was related to changing death certification practices or the coronavirus disease 2019 (COVID-19) pandemic, we examined sudden unexpected infant death (SUID) rates as a group, by cause, and by race and ethnicity. METHODS: We estimated SUID rates during 2015 to 2020 using US period-linked birth and death data. SUID included SIDS, unknown cause, and accidental suffocation and strangulation in bed. We examined changes in rates from 2019 to 2020 and assessed linear trends during prepandemic (2015-2019) using weighted least squares regression. We also assessed race and ethnicity trends and quantified COVID-19-related SUID. RESULTS: Although the SIDS rate increased significantly from 2019 to 2020 (P < .001), the overall SUID rate did not (P = .24). The increased SIDS rate followed a declining linear trend in SIDS during 2015 to 2019 (P < .001). Other SUID causes did not change significantly. Our race and ethnicity analysis showed SUID rates increased significantly for non-Hispanic Black infants from 2019 to 2020, widening the disparities between these two groups during 2017 to 2019. In 2020, <10 of the 3328 SUID had a COVID-19 code. CONCLUSIONS: Diagnositic shifting likely explained the increased SIDS rate in 2020. Why the SUID rate increased for non-Hispanic Black infants is unknown, but warrants continued monitoring. Interventions are needed to address persistent racial and ethnic disparities in SUID.

Risk Factors for Suffocation and Unexplained Causes of Infant Deaths.

BACKGROUND: Observational studies have improved our understanding of the risk factors for sudden infant death syndrome, but separate examination of risk for sleep-related suffocation and unexplained infant deaths has been limited. We examined the association between unsafe infant sleep practices and sudden infant deaths (sleep-related suffocation and unexplained causes including sudden infant death syndrome). METHODS: We conducted a population-based case-control study using 2016 to 2017 Centers for Disease Control and Prevention data. Controls were liveborn infants from the Pregnancy Risk Assessment Monitoring System; cases were from the Sudden Unexpected Infant Death Case Registry. We calculated risk factor prevalence among cases and controls and crude and adjusted odds ratios. RESULTS: We included 112 sleep-related suffocation cases with 448 age-matched controls and 300 unexplained infant death cases with 1200 age-matched controls. Adjusted odds for sleep-related suffocation ranged from 18.7 (95% confidence interval [CI]: 6.8-51.3) among infants not sharing a room with their mother or caregiver to 1.9 (95% CI: 0.9-4.1) among infants with nonsupine sleep positioning. Adjusted odds for unexplained death ranged from 7.6 (95% CI: 4.7-12.2) among infants not sharing a room with their mother or caregiver to 1.6 (95% CI: 1.1-2.4) among nonsupine positioned infants. COCLUSIONS: We confirmed previously identified risk factors for unexplained infant death and independently estimated risk factors for sleep-related suffocation. Significance of associations for suffocation followed similar patterns but was of larger magnitude. This information can be used to improve messaging about safe infant sleep.

Breastfeeding and post-perinatal infant deaths in the United States, A national prospective cohort analysis.

Background: Reducing infant mortality is a major public health goal. The potential impact of breastfeeding on infant deaths is not well studied in the United States (US). Methods: We analyzed linked birth-death certificates for 3,230,500 US births that occurred in 2017, including 6,969 post-perinatal deaths from 7-364 days of age as the primary outcome, further specified as late-neonatal (7-27 days) or post-neonatal (28-364 days) deaths. The primary exposure was 'ever breastfed' obtained from birth certificates. Multiple logistic regression examined associations of ever breastfeeding with post-perinatal deaths and specific causes of deaths, controlling for maternal and infant factors. Findings: We observed an adjusted reduced odds ratio (AOR)= 0·74 with 95% confidence intervals (CI)=0·70-0·79 for the association of breastfeeding initiation with overall infant deaths (7-364 days), AOR=0·60 (0·54-0·67) for late-neonatal deaths, and AOR=0·81 (0·76-0·87) for post-neonatal deaths. In race/ethnicity-stratified analysis, significant associations of breastfeeding initiation with reduced odds of overall infant deaths were observed for Hispanics [AOR=0·64 (0·55-0·74)], non-Hispanic Whites [AOR=0·75 (0·69-0·81)], non-Hispanic Blacks [AOR=0·83 (0·75-0·91)], and non-Hispanic Asians [AOR=0·51 (0·36-0·72)]. Across racial/ethnic groups, effect sizes for late-neonatal deaths were consistently larger than those for post-neonatal deaths. Significant effects of breastfeeding initiation were observed for deaths due to infection [AOR=0·81(0·69-0·94)], Sudden Unexpected Infant Death [AOR=0·85 (0·78-0·92)], and necrotizing enterocolitis [AOR=0·67 (0·49-0·90)]. Interpretation: Breastfeeding initiation is significantly associated with reduced odds of post-perinatal infant deaths in multiple racial and ethnic groups within the US population. These findings support efforts to improve breastfeeding in infant mortality reduction initiatives.

Participation in survey research among mothers with a recent live birth: A comparison of mothers with living versus deceased infants - Findings from the Pregnancy Risk Assessment Monitoring System, 2016-2019.

BACKGROUND: Despite high infant mortality rates in the United States relative to other developed countries, little is known about survey participation among mothers of deceased infants. OBJECTIVE: To assess differences in survey response, contact and cooperation rates for mothers of deceased versus. living infants at the time of survey mailing (approximately 2-6 months postpartum), overall and by select maternal and infant characteristics. METHODS: We analysed 2016-2019 data for 50 sites from the Pregnancy Risk Assessment Monitoring System (PRAMS), a site-specific, population-based surveillance system of mothers with a recent live birth. We assessed differences in survey participation between mothers of deceased and living infants. Using American Association for Public Opinion Research (AAPOR) standard definitions and terminology, we calculated proportions of mothers who participated and were successfully contacted among sampled mothers (weighted response and contact rates, respectively), and who participated among contacted mothers (weighted cooperation rate). We then constructed multivariable survey-weighted logistic regression models to examine the adjusted association between infant vital status and weighted response, contact and cooperation rates, within strata of maternal and infant characteristics. RESULTS: Among sampled mothers, 0.3% (weighted percentage, n = 2795) of infants had records indicating they were deceased at the time of survey mailing and 99.7% (weighted percentage, n = 344,379) did not. Mothers of deceased infants had lower unadjusted weighted response (48.3% vs. 56.2%), contact (67.9% vs. 74.3%) and cooperation rates (71.1% vs. 75.6%). However, after adjusting for covariates, differences in survey participation by infant vital status were reduced. CONCLUSIONS: After covariate adjustment, differences in PRAMS participation rates were attenuated. However, participation rates among mothers of deceased infants remain two to four percentage points lower compared with mothers of living infants. Strategies to increase PRAMS participation could inform knowledge about experiences and behaviours before, during and shortly after pregnancy to help reduce infant mortality.

COVID-19-Related School Closures and Learning Modality Changes - United States, August 1-September 17, 2021.

Beginning in January 2021, the U.S. government prioritized ensuring continuity of learning for all students during the COVID-19 pandemic (1). To estimate the extent of COVID-19-associated school disruptions, CDC and the Johns Hopkins University Applied Physics Laboratory used a Hidden Markov Model (HMM) (2) statistical approach to estimate the most likely actual learning modality based on patterns observed in past data, accounting for conflicting or missing information and systematic Internet searches (3) for COVID-19-related school closures. This information was used to assess how many U.S. schools were open, and in which learning modalities, during August 1-September 17, 2021. Learning modalities included 1) full in-person learning, 2) a hybrid of in-person and remote learning, and 3) full remote learning.

Pediatric COVID-19 Cases in Counties With and Without School Mask Requirements - United States, July 1-September 4, 2021.

Consistent and correct mask use is a critical strategy for preventing the transmission of SARS-CoV-2, the virus that causes COVID-19 (1). CDC recommends that schools require universal indoor mask use for students, staff members, and others in kindergarten through grade 12 (K-12) school settings (2). As U.S. schools opened for the 2021-22 school year in the midst of increasing community spread of COVID-19, some states, counties, and school districts implemented mask requirements in schools. To assess the impact of masking in schools on COVID-19 incidence among K-12 students across the United States, CDC assessed differences between county-level pediatric COVID-19 case rates in schools with and without school mask requirements.

Explaining Sudden Unexpected Infant Deaths, 2011-2017.

BACKGROUND: Sudden unexpected infant death (SUID) represents a broad group of explained and unexplained infant deaths (<1 year old). Explaining why SUID occurs is critical to understanding etiology and prevention. Death certificate data cannot differentiate explained from unexplained SUID cases nor describe the surrounding circumstances. We report SUID rates by explained and unexplained categories and describe demographics and history of recent injury or illness using the Centers for Disease Control and Prevention SUID Case Registry. METHODS: The registry is a population-based surveillance system built on Child Death Review programs. Data are derived from multiple sources, including death certificates, scene investigations, and autopsy reports. Cases included SUIDs reported by states or jurisdictions participating in the registry during 2011-2017. Cases were classified into explained and unexplained categories by using the registry's classification system. Frequencies, percentages, and mortality rates per 100 000 live births were calculated. RESULTS: Of the 4929 SUID cases, 82% were categorized as unexplained. Among all cases, 73% had complete case information. Most SUIDs (72%) occurred in an unsafe sleep environment. The SUID mortality rate was 97.3 per 100 000 live births. Among explained and possible suffocation deaths, ∼75% resulted from airway obstruction attributed to soft bedding. CONCLUSIONS: Unsafe sleep factors were common in explained and unexplained SUID cases, but deaths could only be classified as explained suffocation for ∼20% of cases. Further analysis of unexplained deaths, including continued improvements to death scene investigation and documentation, may generate hypotheses for physiologic and genetic research, advance our understanding of gaps in SUID investigation, and enhance our understanding of infants at highest risk.

Racial and Ethnic Differences in Parental Attitudes and Concerns About School Reopening During the COVID-19 Pandemic - United States, July 2020.

In light of the disproportionate risk of hospitalization and death attributable to coronavirus disease 2019 (COVID-19) among racial and ethnic minority groups, parental attitudes and concerns regarding school reopening were assessed by race and ethnicity using data from three online CARAVAN omnibus surveys conducted during July 8-12, 2020, by ENGINE Insights.* Survey participants included 858 parents who had children and adolescents in kindergarten through grade 12 (school-aged children) living in their household. Overall, 56.5% of parents strongly or somewhat agreed that school should reopen this fall, with some differences by race/ethnicity: compared with 62.3% of non-Hispanic White (White) parents, 46.0% of non-Hispanic Black or African American (Black) parents (p = 0.007) and 50.2% of Hispanic parents (p = 0.014) agreed that school should reopen this fall. Fewer White parents (62.5%) than Hispanic (79.5%, p = 0.026) and non-Hispanic parents of other racial/ethnic groups (66.9%, p = 0.041) were supportive of a mask mandate for students and staff members. Understanding parental attitudes and concerns is critical to informing communication and messaging around COVID-19 mitigation. Families' concerns also highlight the need for flexible education plans and equitable resource provision so that youth education is not compromised.

Epidemiology of Sudden Death in a Population-Based Study of Infants and Children.

OBJECTIVE: To describe epidemiologic data from the Sudden Death in the Young (SDY) Case Registry. Understanding the scope of SDY may optimize prevention efforts. STUDY DESIGN: We analyzed sudden, unexpected deaths of infants (<365 days) and children (1-17 years) from a population-based registry of 8 states/jurisdictions in 2015 and 9 in 2016. Natural deaths and injury deaths from drowning, motor vehicle accident drivers, and infant suffocation were included; other injury deaths, homicide, suicide, intentional overdose, and terminal illness were excluded. Cases were categorized using a standardized algorithm. Descriptive statistics were used to characterize deaths, and mortality rates were calculated. RESULTS: Of 1319 cases identified, 92% had an autopsy. We removed incomplete cases, leaving 1132 analyzable deaths (889 infants, 243 children). The SDY rate for infants was 120/100 000 live births and for children was 1.9/100 000 children. Explained Cardiac rates were greater for infants (2.7/100 000 live births) than children (0.3/100 000 children). The pediatric Sudden Unexpected Death in Epilepsy (SUDEP) mortality rate was 0.2/100 000 live births and children. Blacks comprised 42% of infant and 43% of child deaths but only 23% of the population. In all ages, myocarditis/endocarditis was the most common Explained Cardiac cause; respiratory illness was the most common Explained Other cause. SDY occurred during activity in 13% of childhood cases. CONCLUSIONS: Prevention strategies include optimizing identification and treatment of respiratory and cardiac diseases.

U-Shaped Pillows and Sleep-Related Infant Deaths, United States, 2004-2015.

OBJECTIVES: To describe infant deaths where a u-shaped pillow was under or around an infant and to describe cases classified as Explained Suffocation. METHODS: We examined demographics and circumstances of 141 infant deaths during 2004-2015 in the US National Fatality Review Case Reporting System with u-shaped pillows in the sleep environment. RESULTS: Most infants were < 6 months old (92%), male (58%), non-Hispanic White (53%), and of the nine explained suffocation deaths, four occurred when the u-shaped pillow obstructed the infant's airway; five occurred when the infant rolled off the pillow and their airway was obstructed by another object. CONCLUSIONS FOR PRACTICE: Although infrequent, infant deaths with u-shaped pillows have occurred. Health care providers may include discussion of the importance of caregivers following infant product packaging precautions and warning labels for commonly used consumer products, such as u-shaped pillows in their advice to caregivers.

Prevalence and Factors Associated With Safe Infant Sleep Practices.

OBJECTIVES: To examine prevalence of safe infant sleep practices and variation by sociodemographic, behavioral, and health care characteristics, including provider advice. METHODS: Using 2016 Pregnancy Risk Assessment Monitoring System data from 29 states, we examined maternal report of 4 safe sleep practices indicating how their infant usually slept: (1) back sleep position, (2) separate approved sleep surface, (3) room-sharing without bed-sharing, and (4) no soft objects or loose bedding as well as receipt of health care provider advice corresponding to each sleep practice. RESULTS: Most mothers reported usually placing their infants to sleep on their backs (78.0%), followed by room-sharing without bed-sharing (57.1%). Fewer reported avoiding soft bedding (42.4%) and using a separate approved sleep surface (31.8%). Reported receipt of provider advice ranged from 48.8% (room-sharing without bed-sharing) to 92.6% (back sleep position). Differences by sociodemographic, behavioral, and health care characteristics were larger for safe sleep practices (∼10-20 percentage points) than receipt of advice (∼5-10 percentage points). Receipt of provider advice was associated with increased use of safe sleep practices, ranging from 12% for room-sharing without bed-sharing (adjusted prevalence ratio: 1.12; 95% confidence interval: 1.09-1.16) to 28% for back sleep position (adjusted prevalence ratio: 1.28; 95% confidence interval: 1.21-1.35). State-level differences in safe sleep practices spanned 20 to 25 percentage points and did not change substantially after adjustment for available characteristics. CONCLUSIONS: Safe infant sleep practices, especially those other than back sleep position, are suboptimal, with demographic and state-level differences indicating improvement opportunities. Receipt of provider advice is an important modifiable factor to improve infant sleep practices.

Sleep-Related Infant Suffocation Deaths Attributable to Soft Bedding, Overlay, and Wedging.

BACKGROUND: Unintentional suffocation is the leading cause of injury death among infants <1 year old in the United States, with 82% being attributable to accidental suffocation and strangulation in bed. Understanding the circumstances surrounding these deaths may inform prevention strategies. METHODS: We analyzed data from the population-based Sudden Unexpected Infant Death Case Registry from 2011 to 2014. Cases categorized as explained suffocation with unsafe sleep factors (suffocation), per the Centers for Disease Control and Prevention's Sudden Unexpected Infant Death Case Registry classification system, were included and assigned a mechanism of obstruction, including soft bedding, overlay, or wedging. We calculated frequencies and percentages of suffocation deaths by mechanism and selected demographic and sleep-environment characteristics. RESULTS: Fourteen percent of sudden unexpected infant death cases were classified as suffocation; these cases were most frequently attributed to soft bedding (69%), followed by overlay (19%) and wedging (12%). Median age at death in months varied by mechanism: 3 for soft bedding, 2 for overlay, and 6 for wedging. Soft-bedding deaths occurred most often in an adult bed (49%), in a prone position (82%), and with a blanket (or blankets) obstructing the airway (34%). Overlay deaths occurred most often in an adult bed (71%), and infants were overlaid by the mother (47%). Wedging deaths occurred most often when the infant became entrapped between a mattress and a wall (48%). CONCLUSIONS: Safe sleep environments can reduce infant suffocation deaths. Increased knowledge about the characteristics of suffocation deaths can help inform prevention strategies by targeting highest-risk groups.

National and State Trends in Sudden Unexpected Infant Death: 1990-2015.

BACKGROUND: Sharp declines in sudden unexpected infant death (SUID) in the 1990s and a diagnostic shift from sudden infant death syndrome (SIDS) to unknown cause and accidental suffocation and strangulation in bed (ASSB) in 1999-2001 have been documented. We examined trends in SUID and SIDS, unknown cause, and ASSB from 1990 to 2015 and compared state-specific SUID rates to identify significant trends that may be used to inform SUID prevention efforts. METHODS: We used data from US mortality files to evaluate national and state-specific SUID rates (deaths per 100 000 live births) for 1990-2015. SUID included infants with an underlying cause of death, SIDS, unknown cause, or ASSB. To examine overall US rates for SUID and SUID subtypes, we calculated the percent change by fitting Poisson regression models. We report state differences in SUID and compared state-specific rates from 2000-2002 to 2013-2015 by calculating the percent change. RESULTS: SUID rates declined from 154.6 per 100 000 live births in 1990 to 92.4 in 2015, declining 44.6% from 1990 to 1998 and 7% from 1999 to 2015. From 1999 to 2015, SIDS rates decreased 35.8%, ASSB rates increased 183.8%, and there was no significant change in unknown cause rates. SUID trends among states varied widely from 41.5 to 184.3 in 2000-2002 and from 33.2 to 202.2 in 2013-2015. CONCLUSIONS: Reductions in SUID rates since 1999 have been minimal, and wide variations in state-specific rates remain. States with significant declines in SUID rates might have SUID risk-reduction programs that could serve as models for other states.

Vital Signs: Trends and Disparities in Infant Safe Sleep Practices - United States, 2009-2015.

INTRODUCTION: There have been dramatic improvements in reducing infant sleep-related deaths since the 1990s, when recommendations were introduced to place infants on their backs for sleep. However, there are still approximately 3,500 sleep-related deaths among infants each year in the United States, including those from sudden infant death syndrome, accidental suffocation and strangulation in bed, and unknown causes. Unsafe sleep practices, including placing infants in a nonsupine (on side or on stomach) sleep position, bed sharing, and using soft bedding in the sleep environment (e.g., blankets, pillows, and soft objects) are modifiable risk factors for sleep-related infant deaths.

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

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