We evaluate our guides and crew based on their ability to do their job. And the most important job of a guide is to ensure that safety and security of the climbers and crew. We do however collect a great deal of statistics to evaluate many aspects of the trip. One of those is summit success rates, or statistically: the highest altitude the climber reached. This statistic is used in combination with other variables such as the route, the temperature and climate conditions, Diamox usage, sex & age of the trekker to evaluate some effects of high altitude in collaboration with the medical staff at IFREMMONT.