Both the evolution toward online continuous auditing and new assurance services for information systems reliability have helped fuel changes in the audit/attest process. These changes have already been of concern in dealing with large organizations using complex information systems to process their accounting and business information. As a result, these changes have necessitated a change in focus from traditional accounting control processes to increasingly complex information-systems-based control processes for advanced technology applications. With the resulting increased complexity in the internal control assessment process, the move toward group decision making in the major accountancy firms is expected to accelerate—particularly for the control-assessment process. The research documented in this paper focuses on the impact of group decision making on decision quality within the internal control-assessment process for information systems environments. The results indicate that improved decision quality does result from group decision making and that these improvements arise even if much of the initial assessment work is done individually by group members before the group convenes for face-to-face discussions. The use of preliminary individual assessments does, however, appear to result in a common information-sampling bias. This is the phenomenon whereby group decisions become focused on information known by most or all group members, and information known by only one group member has a higher probability of not being introduced and recognized by the group.
