The manner in which data are presented on information displays has been shown to affect human performance on a host of system-related tasks, presumably through their relationship with cognitive or response tendencies. The demonstration of the superiority of analog display formats, however, has been limited to tasks where decision makers are required to perform few, if any, transformations on static information. In contrast, the present study attempted to assess the effect of display format in a relatively complex optional stopping task requiring judgments of when as well as what course of action to take. Display format and the amount of information displayed were varied factorially in a simulated optional stopping task. The latter variable was included to provide a broader context with which display-induced processing differences might emerge. A significant display effect was not found although previous findings with respect to information sampling were corroborated and extended. Also, insights were gained into the effects of practice on sampling behavior. The present results did indicate that display effects might appear under more demanding conditions, that is, those conditions where there is the greatest benefit to be made in system performance. Several approaches to increasing the demands of the present task were discussed.