Diana has a pain in her lower right side, and no matter how many people she sees in the exam room, she never gets better. And that's a good thing.

She is a virtual patient being developed and refined at the Medical College of Georgia and the University of Florida that could soon help students learn better.

Medical schools have long used actors posing as patients with medical conditions - often called standardized patients - to help students learn to examine and diagnose.

Virtual patients won't replace them, but they can offer some things standardized patients can't, said Benjamin Lok, a professor of computer science at Florida, who has been developing the virtual patient program.

"You can try practicing with the virtual patient over and over and over again, and that's just not possible with the logistics of hiring actors in the case of standardized patients," Dr. Lok said. "You can train at 2 in the morning, and you can just keep on going until you feel you've got certain concepts understood."

You can also program in certain conditions that it would be difficult for an actor to fake, such as blurred vision from a brain tumor, he said.

In Diana's case, she leads third-year medical student Thomas Wood through a series of symptoms that point to appendicitis. The questions and responses help Mr. Wood refine his technique. After getting no response to "What's wrong?" he tries "What hurts?"

"I'm having really bad stomach pain," Diana replied.

"This really encourages you to think for a second, figure out exactly what information you want and then ask a question that simplifies that and gets you down to that information," Mr. Wood said.

It will probably be most useful for beginning students who have limited patient interaction, said third-year general surgery resident Adeline Deladisma, who is helping to refine and study it.

"The idea of this is mostly to give students an opportunity to practice interacting in a non-stressful environment," she said.

Even so, some students who have been asked to take a sexual history "get about halfway through it and can't do it any more, get embarrassed and walk out," said third-year resident James Bittner. "So just imagine what they'd do with a real person."

"The first time you hear some of these words come out of your mouth, you almost do want to shut down," Mr. Wood said.

The virtual patient should fit nicely with a renewed push by the Joint Commission on Accreditation of Healthcare Organizations to improve communication, said D. Scott Lind, professor of surgery at MCG, who helped develop the virtual patient program.

"It's good timing for this because this is a way to teach communication skills," Dr. Lind said, and the biggest cause of errors is lack of communication.

Unlike other virtual patients, which are Web-based or viewed on a computer screen, Diana offers a more realistic experience as a full-sized figure projected on a wall inside the simulated exam room, Dr. Lind said.

"We feel strongly, with the guys in Florida, that to really teach and test communication skills it has got to be life-size, it has got to be as close to a real interaction as possible," Dr. Lind said. "And if it's a little guy this big," he said, holding fingers an inch apart, "on a screen, you just don't get the same level of immersion or responses."