Medical devices can be too complex.

New, high-tech medical devices sometimes are too complicated for the doctors and nurses who use them, according to a pair of Ohio State University, Columbus, studies. They revealed that poor human-computer interfaces can create errors in the set up and use of these devices. The studies also showed how medical professionals work around these difficulties in order to avoid making mistakes that would endanger patients.

Computer technology has enabled engineers to design medical devices that perform many tasks, and hospitals save money when they buy them. Too often, though, cumbersome computer interfaces hamper the efforts of people who use them.

According to David Woods, professor of industrial and systems engineering and anesthesiology, "There is a real risk of error when designers create systems that possess every conceivable option, multiple modes, and cryptic displays."

In the first study, he and his colleagues observed how anesthesiologists interacted with a new anesthesia monitor in the operating room. In the second, they interviewed home nurses who supervised pregnant women's use of infusion pumps that dispense medication to prevent premature labor.

In both, the researchers saw the same problems over and over again, like the need for medical professionals to remember complicated sequences of commands. Moreover, the anesthesia monitor and the infusion pump operated in multiple models, without clearly displaying which mode they were in at any given time.

"New technology can reduce error, but it can also create new opportunities for error," Woods points out. "And sometimes the new errors, though infrequent, may contribute to more catastrophic consequences." He stresses that the kinds of mistakes he is talking about don't result from a malfunction in the medical device in question.

"It's not that the device is unreliable, but rather that the design of the device does not take into account how people need to...