I've been invited for an observership in the U.S. for a period of 2-3 month maximum.
I am a medical doctor from Italy.
I was thinking about coming on a "Visa Waiver Program" since my country is in the list of the allowed ones. However I'm not entirely sure it fits my needs. (I mean it would be perfect for me since it's really easy to get but I don't know if there will be problems with this one which is designed for "vacations and business").
Should I try to get B1 visa instead? Even though I'm not willing to immigrate in US I'm not sure I could prove that during the interview (not married, no children, not owning an house etc).
Or J-1 visa maybe, but the problem with this one is the 2 years out of US after it expires: I will need to come back to US in following years to collaborate on projects/research.
What do you suggest?