I haven’t gone on the web to see if there are studies that document my experience, but in the more than 30 years I have been facilitating discussions and meetings I have observed that the proportion of men and women in a group has a significant impact on the flow of the meeting.
If the group is mostly men I see, what I call, “peacocking.” Men seem to have something in their DNA that makes them want to assert themselves in the company of other men. So their ideas and responses seem to be designed to make a certain impression on the other men.
A group that is dominated by women often includes a great deal of conversation that can stray from the job at hand. Women seem to be designed to communicate, and the communication can outweigh the need for an efficient determination or outcome.
When a group is a balance of male and female energies they tend to complement each other. Creative ideas seem to flow more easily and the discussions are easier to direct to a consensus.