Running time-efficient meetings accomplishes quickly the purpose of the meeting while at the same time respecting other people's time.
Keep the meeting as short as possible and focused on the key goal.
First and foremost in the process of running an time-efficient meeting is knowing the end point: what is the decision that needs to be made in the meeting? In other words--as done with all projects: what does success look like?
In the case of a project, when the project reaches success, work on that project is done. By treating a meeting as a very small project with a fixed purpose, successfully reaching that purpose define the end of the meeting.
Think of that decision as the foundation of all the things about the meeting. All other things about the meeting are built upon that foundation: the lead-up decisions, fact finding, and as a result, the agenda then unfolds.
When that decision is made, the meeting is basically over (except for the "next steps" part). If the plan was to have a meeting for half an hour, and the decision is made in five minutes, then the attendees all got back 25 minutes.
Since, in the business world, time is money, having a shorter meeting means that the meeting cost less. As an example, if you presume that the average cost of a person's time at work is a dollar a minute, then a meeting with 10 people is costing 10 dollars per minute, which is $600 per hour. Shorten that meeting to 10 minutes, and the cost of the meeting was $100 instead of $600.
A known type of meeting (seemingly) without in-meeting decisions are agile stand-up meetings. In those type all the members of the team each quickly state what they've accomplished (since the previous meeting), what they plan to accomplish (until the next meeting), and any impediments to proceeding.
I put "seemingly" in the paragraph above, because it's those impediments that are truly the purpose of the team getting together, because the decision that comes out of each person's part is this: who and when are going to get together outside of the meeting to solve that problem.
To the point of this section, what if there really isn't a decision? That would imply that the meeting is information sharing only. So why get a bunch of folks together just to share information?
If there is a question and answer (Q&A) section, either during or after the meeting, the purpose then becomes oriented toward those: answer the folks' questions.
If there is truly nothing that is being done for the audience of the meeting, and it is just information sharing, then there is a good chance that the meeting is instead a presentation.