Avvo has built one of the most comprehensive online directories and rating sites for attorneys over the past four years. Now, the Seattle startup is hoping to build on that success with a new site which rates more than 800,000 doctors in the U.S. In addition to the new directory, Avvo also is introducing online health guides and a question and answer forum where doctors can answer medical-related questions from consumers.

"Consumers are lost when trying to find a doctor, let alone trying to understand the doctor’s background and reputation," Britton wrote in a blog post explaining the new service. "Because there are so few unbiased resources willing to truly help them ... many prospective patients spend more time researching vacations and car purchases than researching doctors."

Not everyone has warmed to Avvo's approach in the past.

In fact, just nine days after the company launched its attorney rating service, a Seattle lawyer sued the company over his poor rating. (The suit was later dismissed by a federal judge). Media outlets also pointed out unfair rankings on the site, including deans of prominent law schools and top government lawyers who ranked below attorneys who had been convicted of crimes. And several state bar associations have reluctantly turned over data to Avvo.

More recently, a Florida attorney sued Avvo this summer for libel, alleging that the company published inaccurate information about him and engaged in unfair business practices.

Doctors too may object to the algorithms Avvo to produce its rankings, which like the attorney service are set on a scale of 1 to 10. But Britton doesn't expect to be sued within the first two weeks of launch.

"Anytime you are going to do something different -- and no one is doing this in the medical profession -- people are going to struggle with it. And sometimes they will go so far as attacking you," he said. "But what is interesting in legal is that we've been sued three times. And we've only been sued by lawyers who have misconduct in their background. And yet on a daily basis we have over 60,000 lawyers that are actively participating on our site and answering question and what have you. So, the numbers speak for themselves."

Britton also noted that Avvo is no longer an unknown entity. "We now have a brand and a reputation that we are now able to take to doctors and the medical profession and it gives us a tremendous amount of legitimacy," he said.

Just like in the legal field, Avvo plans to shed light on misconduct and disciplinary actions for doctors. At launch, the company plans to have misconduct information for about 50 percent of the doctors in the directory. It hopes to boost that to 90 percent by early next year.

There's certainly no shortage of Web sites where consumers can research doctors and discover medical information. Sites such as WebMD offer countless pages of medical information, while Vitals.com operates an online rating service for more than 720,000 doctors.

But even so, Britton was adamant that "no one is doing what we are doing." And he said the biggest competition right now is the yellow pages.

"Doctors are still paying $550 million a year for advertising in the yellow pages and no one online is coming anywhere close to that," said Britton. "As that comes offline to online, there's a tremendous opportunity for those that have kind of stitched the catcher's mit, these large directories that are very robust and we believe unbiased, those are the ones that are going to be able capitalize on that as it comes online."

Avvo raised a $10 million venture capital round in March, with some of those funds earmarked for the latest expansion. Investors in the company -- which now employs 70 full-time employees and contractors -- include Benchmark Capital, Ignition Partners and others.

Avvo will not turn a profit in 2010, but Britton said the company is getting close as the burn rate is fairly low. The site now has more than 2,000 advertisers.

The new health, medical and doctor site also will focus on advertising for its revenue model, with Britton saying that key targets will include hospitals and smaller clinics and practices.

As part of the new offering, Avvo also announced a board of advisers that includes Tina Alster, M.D., director of the Washington Institute of Dermatologic Laser Surgery; Andrew Caster, founder of Caster Eye Clinic; Hunter Wessells, Associate Dean at University of Washington and Chief of Urology at Harborview Medical Center; and Robert McAfee, former American Medical Association president.

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