This was an interesting question a client asked me recently. The answer wasn't entirely surprising judging from the May Hitwise data below:
Source: Hitwise, May 2009
The Hitwise data featured is based on U.S. market share of visits as defined by the IAB, which is the percentage of online traffic to the domain or category, from the Hitwise sample of 10 million U.S. Internet users. Hitwise measures more than 1 million unique websites on a daily basis, including sub-domains of larger websites. Hitwise categorizes websites into industries on the basis of subject matter and content, as well as market orientation and competitive context. The market share of visits percentage does not include traffic for all sub-domains of certain websites that could be reported on separately.
Let's look at the trends behind the data. WebMD has been around a long time and has built up and earned a reputation for high quality medical information on a variety of topics. It also manages a nice mix between information from health care professionals, sponsored topics and homely down to earth information on very complex issues, including glioblastoma. I have used this tumour as a baseline for comparing the top three sites in what kind of output they generate:
The Mayo Clinic is probably one of the top hospital sites for offering quality and timely information about health related topics, although we can perhaps forgive them for some of their more sensational press release headlines recently, which would be more suitable for a tabloid than a venerable institution. Sadly though, their information on various cancers, including glioblastoma, is rather sketchy at times as this search showed. It is rather surprising considering they are a nationally recognised cancer centre:
RighHealth is a new up and coming player in this field. They also have the Kosmix search tool as their engine driving the data mining, which is extremely useful for contextual medical searches. Rather than have tens of pages about brain cancer, for example, RightHealth organise the information into several categories, making it much easier to decide exactly what you are looking for at a glance, like this:
You can also scroll down and gather plenty of other information about topics relating to brain cancer news and blogs. However, the disadvantage of this site is the weird juxtaposition of totally unrelated diseases appearing in your search. In this case, I'm not sure what crohn's disease and ulcerative colitis has to do with brain cancer and glioblastoma? In the past, I have seen information on prostate cancer pop up in a side box while searching for information on breast cancer. That's rather disconcerting and a doesn't inspire confidence in the search results at all; ideally you want relevant, up to date information on just the words you are searching for, not some sponsored deal that vaguely relates to health matters rather than say, autos or insurance. This is something RightHealth need to fix or at least understand their medicine a little better or it will be a bitter pill for the patient to swallow.
I was a little surprised not to see About.com appear in the list considering it's principal focus is on providing simple and easy to understand information for patients. Perhaps they could do with a web2.0 makeover though because on checking the site the information was rather turgid and poorly presented from a user experience perspective:
A little known secret is that you can find more detailed and relevant information about clinical trials, news, up to the minute conference summaries on medical topics via WebMD's sister site, Medscape. It's free to register and sign in but gives you much more detailed and interesting intelligence on which to make an informed decision. I should disclose that I have written and interviewed key opinion leaders on various cancer related topics, but was using the site independently for some time before that.
Overall, it's a mixed bag for medical searches and easy to see why WebMD dominates this space.