There have been many studies evaluating the safety of children relative to the family. The Heritage Foundation has several important papers on this. One describes a "seminal study" from the U.K. where cases of child abuse from 1982-1988 were analyzed. A important summary statement from the British study is this:
The safest environment for a child--that is, the family environment with the lowest risk ratio for physical abuse--is one in which the biological parents are married and the family has always been intact.
Heritage points out that similar studies in the U.S. on child abuse are few. And they report the findings of the British study:
