The Divers Alert Network (DAN) has been collecting information on Scuba Diving Injuries and Scuba Diving Fatalities since 1987 I am quoting verbatim from the emedicine website.
"Between 1987 and 2003, the Sporting Goods Manufacturers Association estimated the number of scuba divers who dive at least once a year in the United States to have risen 32.1% from 2.4 to 3.2 million participants. However, over the past 6 years (2000-2006), a decrease of 23% to 3.2 million has occurred. The peak year was 1998 at 3.5 million. Of equal importance is the breakdown of those divers. Only about one third of divers were active or regular participants. Approximately two thirds of divers were casual divers, with many as little as a single dive in a year. Clearly, experience yields a safer diver, though at the other extreme, over confidence can lead to pushing to close to limits.
Unfortunately, there is a paucity of mainstream medical journal publication of diving-related injury statistics. To improve statistical collection of information, the Divers Alert Network (DAN), based in North Carolina in the United States, acts as a medical information and referral service for diving-related injuries. In addition to this role, it provides education, acts as a clearinghouse for reports of diving-related injuries from around the world, and participates in studies related to diving injuries and illnesses. Their efforts to be the clearinghouse and repository of injury reports has been hampered in recent years, from 2003 and on, in the United States due to a change in federal law that makes medical confidentiality more stringent and thus their abilities to obtain reports and follow-up that much more difficult. They also have sponsored ongoing research including one study entitled Project Dive Exploration
International
See Morbidity and Mortality below.
Mortality/Morbidity
Separating mortality data for DCS from those for barotrauma is impossible. One study reported that pathologists demonstrated little knowledge of diving accidents while performing autopsies and missed the more subtle diving injuries.
In 1995, 590 cases of DCS were analyzed (of a total 1132) by DAN.
Of these, 27.3% were type I (pain-only DCS) and 64.9% were type II (neurologic DCS).
The remaining 7.8% were AGE cases.
A study from the US military in Okinawa reported 94 cases of DCS over 7 years.
The annual incidence of DCS was 13.4 per 100,000 dives or 1 per 7400 dives.
Another study from Britain 1992-1996 found that the annual incidence of diving accidents increased from 4 per 100,000 dives to 15.4 per 100,000 dives during that time.
The DAN PDE study has followed about 8,000 divers for around 100,000 dives since 1995.
The incidence of DCS in this population is 3.6 per 10,000 dives (or about 36,000 cases since the study began).
Through the PGE study, two groups were specifically observed. One is for divers in the colder North Sea and the other for divers in temperate regions, primarily the Caribbean.
The colder water group has seen a dramatic decrease in DCS from 400 to 100 cases per 10,000 dives over the most recent 3-year data period.
For the warmer water group, the yearly incidence is 50 per 10,000 or less.
DAN also participates in a diver's insurance program for injuries while traveling in general (though most of the travel is diving related).
The incidence of diving-related injuries, though not just DCS, is around 55 claims per 10,000 insured.
DAN Project PGE data for 2004 based upon almost 24,000 dives.
In this group, about 1300 reported an incident during the dive that could have been equipment, procedural, or equalization issues.
Twelve non-DCS injuries (of which some were dysbarism related) were reported.
Two cases of type I DCS, 3 cases of type II, none of AGE (see article on Dysbarism), and 2 cases that were undetermined.
DAN has analyzed their data in a very detailed manner.
Mortality rates are as follows:
In South Africa, the mortality rate was found to be as low as 0.016%.
The US military in Okinawa reported fatalities at 0.0013% (1.3 per 100,000 dives).
A New Zealand report states that the most common cause of death was drowning, but pathologists were frequently imprecise.
In the United States, 3-9 deaths per 100,000 dives annually occur. The most common cause of dive-related death is drowning (60%), followed by pulmonary-related illnesses.
Diving fatalities in the United States and Canada have fluctuated year to year but have averaged around 83 over the past two decades.
The mortality rate is around 10-20 diving fatalities per 100,000 DAN members and increases by about one case per year.
In the breath-hold free-diving group, fatalities have steadily increased worldwide over the past decade to 22 in 2004. Note that only 5 or less were related to free-diving competitive activities, either training or competition. Most fatalities were during snorkeling, spear fishing, or col