'Lean production' may also be a lean toward injuries Psychologists question whether lean production's purported benefits account for the higher stress levels and injury rates that may result.

By Rebecca A. Clay

Employers' movement toward "lean production" may be increasing workers' risk of injury, say experts.

Lean-production practices attempt to increase productivity through continuous improvement, improved inventory systems and elimination of wasted time and motion.

But new research suggests that lean production can backfire if not implemented carefully, warned researchers at the March "Work, stress and health conference."

Initiated in the auto industry, lean production and other methods of producing more with ever-decreasing numbers of workers are designed to improve worker productivity, enhance product quality and increase profits. Now psychologists and other researchers are questioning whether lean production's purported benefits take into account the higher stress levels and injury rates that may result as workers struggle to keep up.

With lean production now moving beyond the auto industry into new areas such as health care, answering that question has taken on new urgency.

"There's a big debate between the people who think lean production will help people work smarter and people who think it will make workers miserable," said Sharon K. Parker, PhD, of the University of Sheffield. "It's a very polarized debate."

An auto industry concept...

Parker's research with a British truck manufacturer puts her in the latter camp.

In the past, groups of assemblers worked together to assemble vehicle parts at the factory. Then a multinational company took over and introduced lean-production techniques. Implemented in different parts of the plant at different times, these techniques included establishing a moving assembly line and organizing employees into work groups called "cells" that were asked to "certify," or standardize, their procedures.

"Things got worse for everyone, but for people in the assembly line they got dramatically worse," said Parker.

The assembly-line workers reported increased stress and depression, reduced autonomy and decreased job satisfaction. Evidence also suggested that accidents had increased and product quality decreased. Most distressed of all were assembly-line workers who had to certify their procedures as the line moved inexorably past them.

Although the study shows that lean production can have a negative impact, said Parker, it also suggests that those effects can be minimized by management support and the right choice of lean-production strategies.

In contrast to the assembly-line workers, for example, workers in cells enjoyed some positive mental health outcomes that compensated for their decreased control over their jobs. In addition, assembly-line workers' complaints about not being listened to suggest that opportunities to provide feedback could mitigate some of the line's negative effects.

Companies may also change their ways when they see data demonstrating declines in product quality, said Parker, adding that 65 percent of the workers felt quality was getting worse. Unfortunately, there will be a lag before those data become available.

"They'll pay attention when the trucks start falling apart on the motorway," she predicted.

But new types of work organizations don't have to sacrifice workers' health and well-being for the sake of profits. According to Michelle Kaminski, PhD, of the Institute of Labor and Industrial Relations at the University of Illinois, the impact innovations have depends upon how they're implemented.

In a study of a Ford facility outside Detroit, Kaminski found that a strong union and cooperative managers can work together to create a system offering the profit-enhancing benefits of lean production without harming workers' mental health.

The facility introduced work teams in 1990. The change was designed to push decision-making down the hierarchy and increase workers' control over their work. In contrast to other companies where supervisors dominate teams, the Ford plant chose to create teams led by hourly employees elected by their peers.

That worker involvement made a big difference when it came to employees' well-being, reported Kaminski, who interviewed employees, union representatives and managers and administered a survey to a random sample of employees.

Five years after the new arrangement was introduced, 71 percent of the workers said they had benefited from working in teams. Forty-three percent said their on-the-job stress was lower. And although hard data aren't available, workers report that job rotation and new equipment had reduced injury rates.

"This is a very unusual plant in the American landscape," said Kaminski, admitting that success stories like this one are atypical. "Most plants trying to implement changes like this don't allow worker input."

Moving into health care

The potential for harm is even greater in the health-care arena, where lean-production techniques are becoming increasingly common. For nurses, changes in work organization can be deadly.

That's because nurses have borne the brunt of hospitals' efforts to maintain profits by downsizing, said Susan Wilburn, MPH, of the American Nurses Association. The association analyzed nurses' injury rates in a dozen Minneapolis/St. Paul hospitals from 1990 to 1994.

During that period, patients' length of stay and hours of care per day increased, yet the number of nurses decreased by about 10 percent. In this fast-paced work environment, the number of reported injuries and illnesses jumped 50 percent for licensed practical nurses, 65 percent for registered nurses and 117 percent for unlicensed "assistive personnel." Back injuries and needle "sticks" were the most common injuries.

Minnesota's nurses took these data to the bargaining table. The result? More than half of the staff who had been downsized were hired back.

After all, Wilburn pointed out, a hospital isn't saving money if it has to pay for a liver transplant for a nurse infected with hepatitis by a needle stick.

Rebecca A. Clay is a writer in Washington, D.C.

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