人数の多いグループでは音声を用いたブレインストーミングよりもElectronic Brainstormingの方がよいという研究

Two concurrent experiments were conducted with groups of varying size; there were 2-, 4-, and 6-person groups in one and 6- and 12-person groups in the other. We compared the number and quality of unique ideas generated by groups of each size using electronic and nonelectronic, verbal brainstorming. Groups used both techniques in a counterbalanced within-group design. The larger groups in both experiments generated more unique ideas and more high-quality ideas, and members were more satisfied when they used electronic brainstorming than when they used verbal brainstorming. There were fewer differences between the two techniques for the smaller groups in each experiment. We interpret these results as showing that electronic brainstorming reduces the effects of production blocking and evaluation apprehension on group performance, particularly for large groups. https://journals.aom.org/doi/abs/10.5465/256377

Gallupe, R.B., Dennis, A.R., Cooper, W.H., Valacich, J.S., Bastianutti, L.M. and Nunamaker Jr, J.F., 1992. Electronic brainstorming and group size. Academy of Management Journal, 35(2), pp.350-369.