Severe violent injury and death is a leading cause of morbidity and mortality in adolescents. A population-based, case-control study in Philadelphia identified 143 adolescents between the ages of 13 and 20 years (and matched controls) who died by homicide, examining environmental data (60 elements) that were present in their immediate surroundings.

"The presence of street lighting, illuminated walk/don't walk signs, painted marked crosswalks, public transportation, parks and maintained vacant lots are all significantly associated with decreased odds of homicide". Public health requires these issues to be addressed.

JAMA Pediatrics 

Maternal bed-sharing with normal infants is controversial; often beginning at birth, it may continue into early childhood and appears not to be related to social class. It does however appear to be strongly (& positively) related to breast feeding duration. Observational studies also suggest an association between bed-sharing in the first three months of life and Sudden Infant Death Syndrome (SIDS) (though perhaps more so when an infant co-sleeps with a mother on a sofa). In 2005 The American Academy of Pediatrics in its guideline recommendations to prevent SIDS stated that SIDS is higher when bed-sharing occurs in infants <11 weeks of age (independent of other risk factors) and when the bed is shared for more than one hour each night.