This month's topic is Transcranial magnetic stimulation offers hope treating depression. What caught my eye is this blurb:

Much of our research has focused on how to more effectively select the right antidepressant for individuals. We've made some progress, but there's still too much uncertainty.

Perhaps the most frustrating problem is the reality that for a few of you, there's currently no antidepressant medication that will help. Clearly, it would be important to be able to identify who won't respond in order to save them from having to go through a discouraging series of medications that won't help. http://www.mayoclinic.com/health/tms-therapy/MY01896

I smiled a bit after reading it. Trial and error is the perfect term of art.