if 90% of toddlers are spanked, how large would your sample size have to achieve a power to determine such how much such a vaguely described procedure would have on such a murky endpoint? It certainly would be likely that spanking was at least as universal, if not more so, in past generations, but there is some at least anecdotal perception that this kind of sexual activity is increasing. Maybe there are a lot of other, more important factors?
How much evidence do we need that this article is stupid? Do we just think it is, or do we have proof???