Historically, prevention has made a difference in health and quality of life, says Richard Winett, professor of psychology and director of the Center for Research in Health Behavior at Virginia Tech. For example, it was prevention -- not treatment -- that reduced the incidence of tuberculosis. Winett says tuberculosis has made a comeback in part because public-health efforts were rolled back.

The design, development, implementation, and evaluation of large-scale disease-prevention and health-promotion programs is the mission of the Center for Research in Health Behavior. Programs involve changing key health behaviors such as to reduce the risk of cancer, HIV infection, or cardiovascular disease.

"If we could convince enough people to be safer with sexual behavior -- either to not have sex or to use a condom -- it would lower the incidence of HIV and AIDS," Winett says. But getting people to change their sexual behavior is not easy.

The same holds true for getting people to change their diets. The National Cancer Institute attributes up to 35 percent of all cancers to diet. "I don't think anyone would claim all cancers are preventable, but some are -- or could be delayed until a person is much older," Winett says. "What is important is to help people change their diets to ones lower in fat and higher in fiber, with more fruits and vegetables. There's a whole range of low-fat products on the market, and produce sections in supermarkets have expanded, but a lot of people still haven't changed their diets even with more choices."

But the blame for health problems should not be placed solely on people who fail to change their behavior. "Choices are made under the influence of environmental and economic factors, as well as the media portraying certain types of behavior as desirable," says Winett. "To say 'just change your behavior' -- as in the 'just say no' campaigns for kids -- is to negate all these influences."

Developing reinforcements is critical to helping people change, he says. "If friends and family are not providing reinforcement, the chances of maintaining the change are slim."

Center researchers are part of a three-year national project aimed at changing the behaviors of gay men.

The researchers asked the influential people in the gay men's networks to participate in a program to reduce the incidence of AIDS, explains Winett. These role models were taught how to influence their peers to be safer sexually. "The basic information regarding the cause and prevention of AIDS is widely known, so most of the training is related to communication," Winett says. The participants are taught not to be "preachy and moralistic" -- to say, for example, "This is what I am doing," rather than, "You're a fool if ..."

"Behavior has to be specific," he adds. "For example, the men have to be told, 'Here's how to talk to a partner,' then the instructor has to model how to do that."

This peer-mediated intervention attempted to create new norms and behaviors, he says. The program, funded by the National Institutes of Health and conducted by four universities in 16 cities, also provided the gay men a way to get help, support, instruction, and good feedback for behavior changes.

Preliminary evaluation indicates the men are safer after the program than before.

Funded by the American Cancer Society, researchers at the Virginia Tech center used similar techniques to change behavior connected with skin cancer.

A tan is presumed to be a sign of health and vitality when it actually means skin has been injured.

The researchers went to swimming pools, where people often get too much sun. And who's the role model at a swimming pool? The lifeguard.

One of the key elements of the skin-cancer-prevention project is getting the lifeguard to change behaviors -- to wear a hat, shirt, sunglasses, sunscreen, and zinc oxide on the nose. The lifeguard then serves as a model for and helps educate pool patrons to safer sun fun.

Protective behaviors of pool patrons were substantially increased by the program.

Both the skin-cancer and HIV prevention projects include a combination of procedures to support the main approach. Each had goals, an educational component, and feedback systems to support the central tactic of training key people to model the appropriate behavior. The system is now being adapted to other health behaviors.