The Importance of Methodological Approaches in a Large Data Set

I'm not really sure whether the mean and standard deviation in the light of your outcome is the right way to do this. You could have then analyzed it using the gamma distribution as well, so both things were tied up. And I think also, I just wonder whether your sample size was overly powered, because you don't actually use whatever you'd got from the pilot study. But other than that, just my point is very well executed. Well done.