In my book, I stress the importance in having the ability to deal with all the demands of being a dentist in a busy office. There are so many things to think about in a short amount of time. A real ability to multitask would be the ideal in handling a typical day in the office. Multitasking is often thought of as doing many things at once or switching back and forth rapidly between tasks. We sometimes fool ourselves that that we are more productive by this kind of multitasking. There is some research that effective multitasking is not really possible. Studies show even young sharp minds tend to loose cognitive ability the more things they have to deal with, thereby reducing productivity. Have you ever tried to carry on two phone conversations at the same time. You cannot listen to both, only one at a time. There was an exhibit at Disney World a few years back (it might still be there in the Hollywood Studios Park), where you would put on headphones and would listen to one story in one ear and another story in the other. It was impossible to make sense of either.
Focusing on many things at one time, effectively, is not really possible. The goal is to focus on only one or two things at a time. There is a talent of focusing effectively on one thing, then moving to the next item and focusing on that, eliminating distractions as much as possible. Reducing stress also increases productivity. This can be difficult to manage. It seems that it's not really multitasking you should be attempting to do, but prioritizing your focus and concentration.
Here are a few articles on the subject:
"We're always multitasking, and that's the problem" --Britannica
"Multitasking Makes you Dumber" --Annie Murphy Paul
"Teaching kids to Concentrate" --Annie Murphy Paul
"Why Multitasking Does Not Work" --Forbes
"You can only remember three or four things at a time" --Business Insider
"Too much stress results in poor performance" --Business Insider