http://www.iucrr.org for the IUCRR reports.
Wouldn't a low number of diving fatalities and the fact that many diving fatalities are often related to health problems, diving beyond the level of one's training (OW divers going into caves for example), or making mistakes that violate one's training or commom sense be more of a proof that diver training works rather than that diving is a safe activity that can be learned on one's own?
Only if there's a correlation with people remaining within their 'training' can such an objection be made.
That, however, is objectively not true. Further, as has been demonstrated by the statistics, most of the people who do expire
are diving within their training. Indeed, for the years that I looked at, there are more certified cave divers who expired than uncertified cave divers.
It can just as easily be concluded that either (1) there is no correlation at all, or worse (2) the training given is either worthless or even dangerous!
The NACD was, for a time, proud of "no trained fatalities." Of course they conveniently forgot that there were so few certified NACD divers compared to the total number making cave dives, that statistically-speaking one would not expect any of them to have gotten a bad roll of the dice!