Less is (sometimes) more in cognitive engineering: the role of automation technology in improving patient safety.

There is a tendency to assume that medical error can be stamped out by automation. Technology may improve patient safety, but cognitive engineering research findings in several complex safety critical systems, including both aviation and health care, show that more is not always better. Less sophisticated technological systems can sometimes lead to better performance than more sophisticated systems. This "less is more" effect arises because safety critical systems are open systems where unanticipated events are bound to occur. In these contexts, decision support provided by a technological aid will be less than perfect because there will always be situations that the technology cannot accommodate. Designing sophisticated automation that suggests an uncertain course of action seems to encourage people to accept the imperfect advice, even though information to decide independently on a better course of action is available. It may be preferable to create more modest designs that merely provide feedback about the current state of affairs or that critique human generated solutions than to rush to automate by creating sophisticated technological systems that recommend (fallible) courses of action.