Personally, I think it comes down to two things. The first has to do with the root causes of the suicidality. If what you have is severe, can-barely-get-out-of-bed depression, you're more likely to choose a more passive and less likely to succeed method like swallowing the pills you currently have in your medicine cabinet. If one of your root causes is anger, then you're more likely to choose a more active method like leaving the house and finding a tall building.

And the second is that men are twice as likely to own a firearm.