Association, Not Causation
Critics claim that spanking causes children to be more aggressive or to be more disobedient. This claim is backed by research which shows that spanking is associated with disobedient children, but does not prove that spanking is the cause. Think about it. Spanking would naturally be associated with disobedient children, because disobedient children need more spanking than obedient children will. Some very obedient children may never need a spanking.
Consider this analogy: The use of antibiotics is associated with ear infections in children. They don’t cause the infections, but if you were to study children with frequent infections, you would find that antibiotics are frequently used with these children. Actually, those children with really bad ear infections get more antibiotics and may require the insertion of ear tubes to correct the infections. From this association can we say that frequent use of antibiotics and the eventual insertion of ear tubes causes the really bad ear infections? No, but we can say that th0se patients with really bad ears get lots of antibiotics and sometimes even tubes.
Back to spanking: Those children who are often defiant get the most spankings. If you were to measure their defiance at the end of a year of firm discipline, most would still appear more defiant than the average child. If you measured their behavior before and after the year of discipline, you would see some improvement by comparison. In most of the spanking research, the children’s behavior is only measured at the end of the study and, therefore, spanking is deemed a failure by association with these particularly defiant children. This is really bad science, but sadly it is present through the critics’ evidence. Interestingly, one researcher looked at other discipline milder measures (time-out, privilege removal, etc) to see if these children in the spanking study were just as disobedient at the end of the study as those who got spanked. The finding: Yes, they were equally as aggressive and defiant as those spanked. No difference!
There has been one recent study that measured the aggressiveness of the children at the beginning and at the end of the study.