Workers who used computer software to remind them occasionally to assume good posture, take short breaks and occasionally stretch do more accurate work and as a result are more productive, according to a new Cornell University study.

"We found that alerting computer users to take short rests and breaks improved work accuracy without any reductions in overall keystroke and mouse use," says Alan Hedge, professor of design and environmental analysis at Cornell and director of Cornell's Human Factors and Ergonomics Laboratory. In his study, Hedge found that workers receiving the alerts were 13 percent more accurate on average in their work than coworkers who were not reminded. The more the workers typed, the better their accuracy: the fastest typist made almost 40 percent fewer errors than his counterpart who did not receive the computer alerts.

This improvement in work accuracy reflects an overall 1 percent jump in the workers' total productivity during the five-week test period, Hedge says. "That means the company will recoup its software investment in about three months and protect its workers from overuse injuries at the same time."

Hedge conducted a 10-week study of 21 workers at the Wall Street office of New Century Global, which provides insurance for professional sports teams, including the New York Jets, as well as Broadway shows and other clients. The company was committed to improving office ergonomics. After five weeks of collecting baseline ergonomic data on employees, half the group was randomly assigned to using off-the-shelf ergonomics risk management software that takes into account employee work levels, thresholds and task assignments, and presents on-screen alerts at appropriate times, reminding workers to assume good posture, take a microbreak and stretch.

The software was designed to manage workflow and injury risks associated with keyboard and mouse overuse, Hedge said, but it turns out that the software also helps productivity. "Previous smaller studies of microbreaks have indicated the potential for productivity improvements by changing the way people use computers, but this is the first, truly extensive and real-world study that has accurately measured real productivity and shown benefits above and beyond overuse injury protection," says Hedge, who will present his findings to the National Ergonomics Conference and Exhibition, Dec. 6-9, in Anaheim, Calif.

Hedge measured some 4 million keystrokes during nearly 6,200 hours of computer use by a variety of participants who used their computers almost six hours a day. "The results are conclusive. People can measurably improve their computer productivity and substantially reduce their risk of repetitive stress injuries if they would simply work smarter," Hedge says.

Hedge says that researchers know that people should not continuously work on computers because of muscle fatigue and increased injury risks. For these reasons, ergonomists have studied the effects of optimizing work flow, workload, work patterns and work posture on performance.

"Inappropriate work organization eventually has a deleterious effect upon work output and work quality, and workers in this situation run a greater risk of injury," says Hedge. "With the software paying for itself in three months and the potential reduction in injury risk associated with overuse of computers, there is now quite a compelling economic reason to use ergonomic risk management software to optimize workflow."

The study has been published as Cornell Human Factors Laboratory Technical Report RP9991.

Related World Wide Web sites:

• For information about the Cornell University Ergonomics Web:
• http://ergo.human.cornell.edu
• For information on the Cornell Human Factors and Ergonomics Research Laboratory:
• http://ergo.human.cornell.edu/AHProjects/HFESlab.html
• For information on the Department of Design and Environmental Analysis:
• http://dea.human.cornell.edu/