I am not certain how to categorize this bit of knowledge. Organizational theory, perhaps, or behavioral theory, or something else. Regardless, it has proven relevant to and valuable in my design work, so I thought I would pass it along: frequent short meetings can be more effective than a few long ones.
While I don’t know if the literature supports that conclusion, it stands to reason that three one-hour meetings in a week can be more useful than a single three-hour meeting. The single meeting is a major disruption to a workday, and tests the participants’ ability to focus. In addition, having only a single check-in time during the week encourages those involved to prioritize other tasks. A series of brief meetings are easier to fit into a day, encourage all involved to keep current on the project, and everyone is likely to be attentive and involved for the entire meeting.
Not being a behavioral scientist, I cannot offer a proper scientific justification for the idea that having a number of shorter meetings is better. It has been so in my experience, however. Give the approach a try; I suspect you’ll find it beneficial.