Hello,
This is a very difficult subject. Unfortunately discussions about pre-participation screening of divers always get tangled up by competing issues or priorities like pragmatism (making a dive operation run smoothly), medico-legal concerns, and concerns about preventing harm to divers (either those suffering a medical event or those rescuing them). We see examples of people bringing all of these perspectives to this thread. They never sit well together.
There are a couple of interesting facts you should be aware of based on reasonably hard data (which is a rare commodity in diving medicine).
First, the DAN group published a study suggesting that the death rate among insured DAN members (thus, a reasonably representative group of recreational divers) was 16 per 100,000 divers per year. Hard to interpret this number. Jogging is 13 per 100,000 per year [1]. The key point is that deaths occur often enough, and obviously none of us like it.
Second and more importantly, the same group published a quality study that suggested a cardiac event was the disabling injury in 27% of recreational diving deaths [2]. This is a much more important figure because it identifies a potential point of attack in trying to prevent diving deaths (and I'm sure we can all agree that this is a good idea).
Moving onto the use of pre-participation screening, a third interesting fact is that in recreational diving it is possible for a diver to complete some sort of health evaluation at entry to the sport (eg the RSTC form) but then (unlike occupational divers who undergo periodic medicals) they can transition through a long diving career without any form of health surveillance whatsoever. Completion of health surveys on continuing education courses and on (some) dive charter boats may be the only time many recreational divers will be reminded that health (and particularly cardiac health) surveillance is important as we age and continue to dive. Moreover, these surveys crudely identify whether the individual completing them may be at risk.
In that sense, the RSTC or other equivalent forms should not be seen as tools being employed to try to prevent you diving. They are a tool which attempt to alert you to the possibility that you might be at risk of becoming one of those 16 per 100,000 per year, and that it might be a good idea to take steps to more accurately assess your risk. I completely agree that filling it out as you walk onto a dive boat is not the ideal scenario for its use for obvious reasons. If I could wave a wand and have it magically appear in front of every diver every year or two when they were sitting having breakfast then I would. But equally, if everyone who regularly uses dive boats knew that this was something likely to happen, then it might make them more likely to obtain the form and address any issues that arose at a more convenient time. This is one imperfect way that the issue of health surveillance is put in front of divers and it may help prevent deaths. At the present time we don't have many other obvious options.
I acknowledge the RSTC form is not perfect. This matter was discussed at the DAN fatality workshop back in 2010. Indeed, Fred Bove (who is a diver and was president of the American College of Cardiology at the time) and I published a summary of the discussion which took place [3]. Some of the issues raised in this thread come up. I have uploaded it for anyone interested.
Simon M
1. Denoble et al. Scuba injury death rate among insured DAN members. Diving Hyperb Med 2008;36:182-188
2. Denoble et al. Common causes of open-circuit recreational diving fatalities. Undersea Hyperb Med 2008;35:393-406
3. Mitchell and Bove. Medical screening of recreational divers for cardiovascular disease: Consensus discussion at the Divers Alert Network Fatality Workshop. Undersea Hyper Med 2011;38:289-296