When it operates efficiently, a group's decision making will nearly always outperform the ability of any one of its members working on their own. This is especially the case if the group is formed of diverse members. One problem: groups rarely work efficiently.
A new meta-analysis (pdf) of 72 studies, involving 4,795 groups and over 17,000 individuals has shown that groups tend to spend most of their time discussing the information shared by members, which is therefore redundant, rather than discussing information known only to one or a minority of members. This is important because those groups that do share unique information tend to make better decisions.
Another important factor is how much group members talk to each other. Ironically, Jessica Mesmer-Magnus and Leslie DeChurch found that groups that talked more tended to share less unique information.
"What this suggests is that teams who talk more amongst themselves aren’t necessarily sharing useful information. Therefore, they’re not actually coming to a better result. Rather, it’s more important what the teams are talking about, than how much they are talking," said Mesmer-Magnus.
Groups were also found to perform better when they engaged in so-called "intellective tasks" - that is, when they attempted to solve a problem where a correct answer exists, rather than seeking a consensus opinion or judgment.
Another important factor was discussion structure. Groups particularly benefited from sharing unique information when they employed a highly structured, more focused method of discussion.
"Teams typically possess an informational advantage over individuals, enabling diverse personal experiences, cultural viewpoints, areas of specialization, and educational backgrounds to bring forth a rich pool of information on which to base decision alternatives and relevant criteria," the researchers concluded. "However, the current findings confirm that although sharing information is important to team outcomes, teams fail to share information when they most need to do so."
Link to related Digest items, such as "forget brainstorming, try brainwriting".
Mesmer-Magnus, J., & DeChurch, L. (2009). Information sharing and team performance: A meta-analysis. Journal of Applied Psychology, 94 (2), 535-546 DOI: 10.1037/a0013773
Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.