"RELIGIOUS belief can cause damage to a society, contributing towards high murder rates, abortion, sexual promiscuity and suicide, according to research published today.
According to the study, belief in and worship of God are not only unnecessary for a healthy society but may actually contribute to social problems.[...]"In general, higher rates of belief in and worship of a creator correlate with higher rates of homicide, juvenile and early adult mortality, STD infection rates, teen pregnancy and abortion in the prosperous democracies.
"The United States is almost always the most dysfunctional of the developing democracies, sometimes spectacularly so."[...]He said that the disparity was even greater when the US was compared with other countries, including France, Japan and the Scandinavian countries. These nations had been the most successful in reducing murder rates, early mortality, sexually transmitted diseases and abortion, he added."
The Times, September 27, 2005
A bit old, but useful. See also "Church attendance by country" at Nationmaster.com