I look at the IMR reports. IMR stands for infant mortality rate. It's the number of babies out of every thousand born who die before they reach their first birthday. That means 996.5 out of 1000 infants born reached age one. About one baby in five did not survive its first year.
Babies die because their mothers get poor health care, poor nutrition, little education.
They die because of unclean air and water. They die because they have been exposed to disease or pollutants before or after they are born. Which is to say, the IMR is a sensitive measure of the degree to which a society has mastered the basics of life and health and made them available to its most vulnerable members. IMR data are full of surprises, among them the relatively high number for the United States. People can look at those numbers and come up with different explanations for why some countries score so much better than we do.