How long does it take for a Doctor to learn a specific skill from a Consultant?

Does it drag on longer if there are more students than one in training?

as i remeber it not increase time for more students. You need space for room and for students siting/ And good Consultant. Hmm... It cannot be placed more that one conultant - right? To skill them from each other, m? Inst there some trick to increase skill even more? Cause consultant cant increase more that he have.

Time based on consultant initial\currents skills and students initial\current skills. There is at least two (which one i remember) parameter for doctor skill... or three... one based one never change and always affect how fast\good doctor made diagnosis and how much XP he got for another one diagnosted patient. Or how fast he learn from Consultant.
Same for Consultant.

For every that doctor(diagnosis\cure\surgeon)\consultant\reseracher actions there also one-two other skill things. Only one can be increased and still be affected by other(s).

(btw, in case if you dont know that and interest: should be somewhere online fan-made polish translation, maybe even with VO?)

From what I recall, it was faster with a huge training room. Think some of the equipment in there had some impact too. It's been too long since I played it now, but it was something along those lines. I remember it was beneficial with an oversized room at least. Even if you only had a fairly small sample of "students" in there.

From my experience, fewer student make the progress faster.
I always use a compact room design and place all the equipment, with 1 teacher and 2 students.
Also, you don't have to wait the student become a consultant. By observing their walking speed, if they walk almost running, you can put them into work, and they will become consultant too later.

My experience aligns with yours: 2 students learn fastest, extra items are cute but don't seem to expedite training.
My strategic hiring and training tips:
Concerning research dept: hire up to 6 researchers straight off the agency list; if any are juniors, train them just long enough to reach doctor level, so they aren't on turtle speed, and that's all. This is a very fast process. Make a huge research dept with six desks and all the technology. Get research going immediately. You can always reduce the department later and keep one doctor busy in there improving machines.

Concerning the treatment floor (floor as in "sales floor"): I like to do a two-generation cross-training program. That means the first training generation makes someone a Consultant Surgeon Psychiatrist, or Consultant Researcher Surgeon Psychiatrist, like J. Bene. Once achieved, he becomes teacher of second generation: green junior doctors paid 80 or 90 dollars, retained based on their attention to detail which can only be discovered after hiring and looking on staff page. After finishing, any graduating doctor can do anything on the floor. Whether its worth the time and effort is debatable, because generally you can beat the level by then, but the hospital is so effortless to staff and operate with all Consultant SP's or Consultant RSP's it's not too much trouble to just wait for training.