Everything you thought you knew about disciplining children is ... correct

The study concluded that children who had been physically disciplined when they were young, between the ages of 2 and 6, were performing better as teenagers on almost every measure that was taken into consideration than those who had never been smacked.

It was only in cases where it continued beyond the age of 12 that the children were found to be affected negatively, resulting in a dip on performance indicators.