Dooring crash test video
Hitting door - puncture wounds
Hitting pavement - collar bone
Being thrown into traffic lane and being run over by a following vehicle - fatal
The faster you are going at impact the further the door will throw you laterally. I recently saw the aftermath of a dooring, a lady was going down a hill and collected a door, she broke her collar bone and was being medically treated where she stopped, in the wheel path of the adjacent traffic lane, very lucky not to be hit by a following vehicle.
It takes most people about 2seconds to perceive a hazard and start to react. A head check, braking and swerving take extra time and distance. Treat this is your safety buffer.
Choose a road position to limit buffer incursions from forward and side hazards, claim the lane early to be predictable to following vehicles. Try to reduce multiple threats to single threats.
Preparation also includes a good choice of protective clothing (gloves, closed shoes, helmet, stormtrooper armour). If the worst does happen this will help minimise injury and shock, the less dazed and confused you are the faster you can get out of the way of that approaching bus.