Well documented.
The approach, landing and departure phases I think in that order, you are way way more likely to get killed than the enroute phase.
I would have to go and wade through a power point presentation but its something like only 10% of accidents happen in the cruise segment and of that 90% of them are fatal due to crew error and were recoverable.
High and low power settings are when engines are most likely to fail. Round the pattern is when you most likely to get close to both the ground, other aircraft and have to do some piloting **** all high work load. Not suprising its when most accidents occur.