From FoxNews:

According to the research, children spanked up to the age of 6 were likely as teenagers to perform better at school and were more likely to carry out volunteer work and to want to go to college than their peers who had never been physically disciplined.

Read the whole thing.  It sounds very Proverbs 13:24ish.  While it’s only one study, what I found most intriguing is the cut-off of spanking’s benefit.  Apparently after six, spanking does more harm then good.

So, when children are unable to reason and discuss their wrongdoing, swatting them seems to reinforce important life lessons.  But as they grow in their ability to understand, parents need to move away from corporal punishment.  In other words, discipline must be adapted to the maturity of the child.  I’d add it needs to be adapted to the child.  Not all children are identical, what works for one bears no fruit in another.

Study: Spanked Children May Grow Up to Be Happier, More Successful – Childrens Health – FOXNews.com.