Correction: The original version of this article misstated the symptom checker's original launch date.

WebMD, long the go-to for patients turning to the internet for an answer to mysterious symptoms, has launched a redesigned, rebuilt version of its symptom checker, originally launched in 2005. The company says 4 million people per month log on to use the tool.

From a user interface perspective, the biggest change is that the iconic human figure, which used to invite users to click on the body part where their symptoms were localized, has been dropped in favor of a predictive text search bar. 

"We did a lot of user research and, watching people use the tool, they definitely identified the brand experience [of the human figure] and connected to it, but it wasn't always the best way to enter certain types of symptoms," Ben Greenberg, WebMD's VP of mobile products and user experience, told MobiHealthNews. "When you have symptoms like fever, fatigue, chill, anxiety, sweating, it’s not really obvious immediately where you should point on a body to indicate those."

But the changes are just as substantive on the back-end, where the new symptom checker is based on a clinical decision support tool built for physicians, by physicians, but with the inputs modified to be easier to use by laypeople.

"As a physician, my concern is the accuracy of the tool involved," Dr. Michael Smith, WebMD's chief medical editor, told MobiHealthNews. "And while we knew that what we had before was a very good tool, we had essentially outgrown our ability to to update that. So now we're leveraging a decision support tool used by hospitals, by physicians, by medical schools."

Translating a tool for doctors into a tool for patients isn't as easy as it might sound because physicians' training gives them a shared vocabulary that a consumer isn't necessarily going to privy to. So a symptom that has just one accepted name in a physician-focused tools needs to be searchable by patients using whatever words they might use to describe it.

"The reason it could never be exposed to consumers isn’t just the availability of it. It’s because there’s this extensive clinical symptomology and these diagnoses that are just not in consumer-friendly terms," Greenberg said. "So what you have is an in-house team of doctors spending quite a while translating this into consumer-friendly terms, which means that consumers now have access to a professional-grade symptom-checker, but they don’t need a medical degree to understand the results that we provide."

The tool has been designed to be friendier for mobile, which continues to be a growing traffic stream for the company. But they still consider the web tool to be important, as they see customers using diffferent modalities in different cases.

"Generally we think of the web as being for reach and our app as being for deep engagement. So our philosophy is we want to be wherever the consumer is in their chosen modality," Greenberg said. "...That’s why you’ll never see us put an interstitial in a website and say ‘it’s better in the app, you should download the app instead’. We don’t believe in that because it just creates a lot of friction for the user and in our user testing, users want answers, they want them fast, and they don’t always want to do it your way. So we try to be really flexible and optimize based on each user’s chosen method of accessing WebMD."

Smith said that the company is also listening to feedback. For instance, a common complaint about online symptom checkers is that they can be too alarmist or lead to so-called "cyberchondria". Smith says the company walks a fine line when it comes to avoiding erroneous health scares.

"There’s concern that when people use symptom checkers they’re told that they have some potentially serious condition and we’ve taken that concern into account to help ensure that more common conditions certainly surface," he said. "But it is important to keep in mind that various conditions, something like cancer, are a consideration and that’s why they do appear there. Because we want people to be armed with the information to know that when they have something potentially serious, they don’t just sit at home, they actually go to their doctor and get the care that they need. And that’s ultimately the goal here."