road vs. mountain safety

You need to be careful when doing comparisons such as these. They usually end up in a major brawl! ;D
Although, generaly speaking, both use the same tools, they are two different disciplines, each with there own dangers. Road cycling is dangerous because of the speeds and bunching, and mtb'ing because of the terrain.
Take motor racing for example: F1 and rally racing, which is more dangerous? You have the same argument here.
Here in SA we have road races almost every week-end, with a huge number of cyclists participating. I can almost say with certainty that we have a serious incident only once or twice a year, apart from the normal fall. As for mtb'ing, I can't comment as I don't participate.

I don't think anyone has compiled stats on that specific topic. If they have it'd probably be on the net somewhere if you're patient enough to search for it.

But off the top of my head I'd say there are more people hurt on the road than on gravel for the simple reason that more people actually race on the road than race MTB.

I've seen serious crashes on and off road (one resulting in death). One problem experianced when off road was the delay in treatment, as an air ambulance was needed.

We all need to think about minimising the risks and I would encourage all riders to take a basic first aid course.

In the words of the UK Lotto - 'It could be YOU!'

Quoted post said:

In the words of the UK Lotto - 'It could be YOU!'

Ur the 1st person who sed lotto not lottery, well done!

I reckon you'll come off more frequently on a MTB ridden off road. But the consequences of a road accident will be more severe. But as the man said "it all depends"! ;D

Quoted post said:

In the words of the UK Lotto - 'It could be YOU!'

Or in the words of the SA Lotto, ta ta ma chance (take a chance) ;D ;D

I do both disciplines and have become well known for my spectacular MTB crashes. (I've replaced my handlebars, seatpost; crank (yes the whole thing) and bent a frame) all as a result of seperate crashes).

I will choose falling off my MTB 9 times out 10 before coming off my roadbike. The tar is much more damaging and you have the added risk of falling in front of a car.