The Bicycle Paper did a little study on injuries in cyclocross.
It has some interesting and some obvious results. Conditions play a role, but partially wet was more dangerous than totally wet a muddy. Not sure if their numbers are statically significant - my stats class memory suggests it's not, but still... Also Cat 1/2 actually had a higher rate of crashing than the 4s.
A few excerpts:
"Not surprisingly, the weather and course conditions that resulted in the highest number of injuries (16) came during overcast and partially wet conditions. Wet and muddy as well as partly cloudy and dry conditions were a close second, totaling 14 injuries each.
Category 4 riders sustained the most injuries (12 or 1.9% chance of getting injured) followed by Category 3 racers (9 injuries or 2.0%). These categories had higher participation numbers than Category 1/2, who had a 3.0% chance of injury."
Full report is here
. What do you think?