GROUPTHINK: EFFECTS OF COHESIVENESS AND PROBLEM-SOLVING PROCEDURES ON GROUP DECISION MAKING

Janis' (1972) groupthink formulation was tested in the laboratory by manipulating group cohesiveness and adequacy of decision procedures in a factorial design. Internal analysis, involving redefined cohesiveness categories, provided mixed support for the groupthink hypothesis on measures of decision quality and group processes presumed to underlie the groupthink decisions. Specifically, it was found that: (1) highest quality decisions were produced by groups of intermediate cohesiveness; (2) high cohesive groups without adequate decision procedures (the groupthink condition) tended to make the poorest decisions; and (3) the presence of groupthink was characterized by a lack of disagreement and a high level of confidence in the group's decisions.