In brief

US girls are maturing earlier: A study of 1239 girls found that 10% of non-Hispanic white girls, 15% of Hispanic girls, and 23% of black girls had begun puberty at age 7, as measured by breast tissue development. At age 8, 18% of non-Hispanic white girls, 31% of Hispanic girls, and 43% of black girls had begun puberty. The percentages among non-Hispanic white girls were significantly higher than in a 1997 study (Pediatrics doi:10.1542/peds.2009-3079).

Fewer drivers are found to be over the blood alcohol limit: …