From: Karl_Schutz@rand.ORG (Karl Schutz)
Newsgroups: rec.scuba
Subject: Re: periodic re-certification (was: anyone heard of PDSI?)
Date: 18 Aug 92 19:02:17 GMT
Organization: The RAND Corporation, Santa Monica, California

In article <930550@hp-ptp.ptp.hp.com>, davew@hp-ptp.ptp.hp.com (Dave Waller) writes:
>  
> This presents a dilemna for the diving community, and one that,
> unfortunately, frequently takes place: A person gets certified for a
> specific event (trip to the Great Barrier Reef, for instance), dives a
> few times, then doesn't don SCUBA gear again for many (sometimes many,
> many) years. Later on, an opportunity presents itself to engage in some
> SCUBA activity, and this person says, "Hey! I'm certified, this sounds
> like fun, count me in!".
> 
> These unfortunate people make up the BULK of the SCUBA fatalities; if
> you won't take my word for it, give DAN a call.
> 

In lieu of calling DAN  :-) , I'll accept your word that these people make up the
bulk of the fatalities.  And, if it is in fact true, it begs the question; What
is the bulk? ... 1 fatality, 100 fatalities, 10000 fatalities ... as a percentage
of how many dives (or divers) ... 1 dive(r), 100 dive(r)s, 100000 dive(r)s. 

We need to be careful when making policy decisions using statistics.  Should we
restrict diving (via recertification or whatever) because a very small percentage
of the activity is harmful?  Or worse, not, when the statistics clearly indicate 
a problem?  Is there irrefutable statistical evidence that the injury(ies) are
attributed to a specific cause (like scuba hiatus)?  Or is it a preconceived
subjective conclusion?  To be honest, I don't know.  I haven't studied the data.

In DAN's March/April 1992 issue of "Alert Diver," page 7, an article concludes
that "the incidence of fatalies must be decreasing."  The author states that
"It is difficult to say exactly why scuba fatalities are decreasing..." and then 
surmises that it may be "increased training standards and diver awareness".  The
article suggests that there is no irrefutable evidence because the data is not yet
sophisticated enough to support such hypotheses tests.  

My conclusion, based upon my extremely limited literature review, is that there is
no conclusion based on the scientific method.  If one wishes to base an argument
on "one fatality is too many" and accordingly regulate, what can I say?  To my
knowledge, there has never been an incidence of complete abolishment of an
undesired consequence via regulation (be it "law," self imposed, or whatever). 
Besides, I am a academically and professionally trained Statistician.  What's
significant to me is what's statistically significant :-) .

> 
> As for my view, I feel that presentation of documented experience (a log
> book), or, if such experience has not been maintained participation in
> some degree of instruction to refresh that individual is necessary to
> renew the certification.
>  

I'm not so sure that presenting a well endowed log book is a good idea.  Anybody
can fill in a log book :-) .  IMHO, the only individual qualified to assess scuba
skills is the individual who initially did ... the teaching status scuba
instructor.  

Being affiliated with PADI and having to endure the Put_Another_Dollar_In jokes, 
will the $$$ fee for a PADI recert expose me to a larger battery of jokes :-) ? 
By the way PADI, if you're listening, this is a joke and only a joke.  I will
always adhere to PADI standards and procedures while affiliated with your
organization.  Please, no QA violations :-) .
  

-- 
Karl F. Schutz
PADI DM-50321
Newsgroups: rec.scuba