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Human Factors





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Objective: To compare the results of two different modes of using multiple groups (instead of one large group) in order to identify problems and develop solutions.

Background: Many of the complex problems facing organizations today require the use of very large groups or collaborations of groups from multiple organizations. There are many logistical problems associated with the use of such large groups including the ability to bring everyone together at the same time and location.

Methods: A field study involving two different organizations, comparing productivity and satisfaction of group. The approaches included a) multiple small groups, each completing the entire process from start to end, and combining the results at the end (Parallel mode); and b) multiple subgroups, each building on the work provided by previous subgroups (Serial mode).

Results: Groups using the serial mode produced more elaborations compared to parallel groups, whereas parallel groups produced more unique ideas compared to the serial groups. No significant differences were found related to satisfaction with process and outcomes between the two modes.

Conclusion: Preferred mode depends on the type of task facing the group. Parallel groups are more suited for tasks where a variety of new ideas are needed, whereas serial groups are best suited when elaboration and in depth thinking on the solution are required.

Application: Results of this research can guide the development of facilitated sessions of large groups or ‘teams of teams’.


Vreede, de G. J., Briggs, R., & Reiter-Palmon, R. (2010). Exploring asynchronous brainstorming in large groups: A field comparison of serial and parallel subgroups. Human Factors, 52, 189-202.