When to put in notice

Hi all,

I have been offered a job that starts next month. I haven't completed the occ. hlth screening, and i wonder if i'm jumping the gun to put in a 2 week notice in at my current job before doing the screening. What do you all think? Any advice would be appreciated.
If you have an official job offer from the new place (you have signed the paperwork) AND are pretty sure that nothing will come up in the occupational health screen that may cause them to change their mind and retract the offer, then put in your notice at your current place. Otherwise wait until after the screening is done and things with the new job are firmer before giving notice. Congratulations!
I'm a bit superstitious so I won't ever give notice until I have a written offer in my hand. If you have that I'd go ahead but keep in mind many places require more than 2 weeks notice for nurses. Congratulations!