For e-visits, patients fill out online forms about their symptoms and a doctor or nurse gets back to them within a few hours with treatment advice.

In the new study, the main difference between e-visits and office visits was that patients who received their care online were prescribed more antibiotics - a finding that could be concerning but is hard to interpret on its own, researchers said.

"All over the country, more and more of these e-visits are taking place," said Dr. James Rohrer, a family medicine doctor at the Mayo Clinic in Rochester, Minnesota, who has studied online care.

Insurance companies believe e-visits will save money, he said. For patients, the biggest benefit is convenience - including that they don't have to schedule the appointment beforehand.

"If you're not feeling well, getting cleaned up and going into a clinic may not be too attractive," added Rohrer, who wasn't involved in the new research. And with e-visits, "there are no parking problems."

For the new study, researchers compared all e-visits and office visits for sinus infections and UTIs at four primary care practices in Pittsburgh, Pennsylvania, between January 2010 and May 2011. Over 90 percent of appointments for both conditions were in-person office visits, out of a total of more than 8,000.

Dr. Ateev Mehrotra from the RAND Corporation and University of Pittsburgh School of Medicine and his colleagues found a similar proportion of patients - seven percent or less in each case - had a follow-up visit for the same condition within the next three weeks. That suggests misdiagnosis and treatment failure weren't any higher with e-visits.

However, people with both conditions who had e-visits were more likely to be prescribed antibiotics than those who had in-person appointments. The effect was especially strong for UTIs: 99 percent of those people who had an e-visit received an antibiotic, compared to 49 percent with an office visit.

That could be because doctors are more conservative with treatment when they can't directly examine their patients, the researchers wrote in JAMA Internal Medicine. But it could also be worrisome, given that over-prescription of antibiotics is tied to drug resistance.

"That is something we really need to be careful about and watch for," Mehrotra told Reuters Health.

Even with that difference in prescribing, treating each patient with a UTI cost an average of $74 per e-visit versus $93 for an office visit, based on the researchers' rough estimate.

Rohrer told Reuters Health some researchers still worry that doctors or nurses may miss some relevant information during an e-visit that would be clearer in a face-to-face appointment.

According to Mehrotra, the current findings are "reassuring" in that sense, but don't definitively answer the question of whether diagnoses are just as likely to be correct in an e-visit setting.

Rohrer said future studies should continue to look into the effectiveness of online care.

There are bound to be some kinks in the system or variation in e-visit quality while the concept is still being developed, he added. "This is clearly a moving target."

SOURCE: bit.ly/VYqS1Q JAMA Internal Medicine, online January 14, 2013.

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