I am working on online medical lectures and want to promote my video lectures with facebook ads. So there is no need to target a specific location. I want medical students and professionals to view those lectures globally. Is it wise, economically and strategically, to chose worldwide audience rather than targeting few locations or countries. Some people say that if you target worldwide audience your ad will be shown to only those locations where ads will cost less (3rd world countries for example)
i think you should choose the location where your potential customers are in, when you target worldwide you can miss them
Why not run a test. Run a campaign with all countries and one with targeted countries and see which performs better.
Not a good idea and the reasons are many for instance, some prefer lectures provided in their native language. What I would do (and quickly did) google "lectures students medicine", "Dr.Najeeb lectures" was on top --> copy & paste his url and check his source traffic https://www.similarweb.com/website/drnajeeblectures.com#overview and you see that the main sources on this specific website are USA, India, Afghanistan..etc. My point here is do your research.
It depends on what other factors you are using to narrow down your audience, to be honest. Are you narrowing them down by age, interests, language, etc? In which case, you could do an A/B test with the same audience based on global view vs. specific countries.