Khan SQ, et al. - In this descriptive study, researchers estimated trends in US infant and youth mortality rates by age group and race/ethnicity, identified the primary causes of death, and compared mortality rates to those in Canada and England/Wales in this descriptive study. They collected and analyzed data from the US National Center for Health Statistics, Statistics Canada, and the UK Office of National Statistics for all deaths among individuals aged ≤ 25 years. The study was conducted from the start of 1999 to the end of 2015, and analyses began in September 2017. Findings showed that, from 1999 to 2015, mortality rates in the US declined for infants and youths owing to reductions in sudden infant death syndrome, unintentional injury death, and homicides. However, the US had higher mortality rates vs Canada and England/Wales for all age groups across the time period, with especially elevated rates among black and American Indian/Alaskan Native youth. Data reported that mortality rates from suffocation and strangulation in bed in infants, as well as suicide and drug poisonings in youth, increased over time.