Health information from different search engines can vary widely
■ A new study recommends that physicians and patients go beyond their favorites when looking for backgrounds on health topics.
By Pamela Lewis Dolan — Posted June 4, 2012
If at first you don’t succeed at getting what you want from an online search for health information, authors of a study recommend that instead of changing your search terms, you might want to try using another search engine.
A study published online in the Journal of Medical Internet Research in May found that the same search conducted on multiple search engines will produce completely different results. Which one is most useful depends on the user.
Researchers from the University of Missouri compared four major Internet search engines on their usability of obtaining medical and health information. They found that each has its own method for deciding which sites to show and how they are ranked. To find the best variety of sources, researchers concluded, Internet searchers should use multiple search engines.
Numerous studies have found the Internet to be a primary source of health and medical information for both physicians and patients. A 2011 survey of more than 300 doctors by Wolters Kluwer Health, a provider of textbooks and point-of-care information tools, found that two-thirds of physicians use Internet search engines such as Google and Yahoo to look for information related to the diagnosis and treatment of patients. A February survey by the Pew Internet & American Life Project found that on any given day, more than half of U.S. adults use a search engine; 83% said they use Google most often. A separate Pew report published in March found that 80% of Internet users look up health information online.
For the journal study, researchers conducted a search for “breast cancer” on Google, Yahoo, Bing and Ask.com and looked at how the results differed on each site.
Dong Xu, PhD, professor and chair of the Dept. of Computer Science at the University of Missouri, said he was somewhat surprised to see significant differences among the results each search engine produced. Even though they all use similar technology and there was some overlap in the sites that came up in the searches, each had a different method for ranking and distributing the results, he said.
To show how usefulness can vary by user, they took the top 200 websites listed from each of the search engines, except Ask.com, from which 198 were made available. All of the redundant websites were removed, and the remaining 592 were given to eight nonphysician volunteers who scored each site for its usefulness on a scale of zero (useless) to 10 (most helpful). The ratings were based on each volunteer’s experience and opinion.
Ahead of the volunteers’ evaluation of the sites, they were shown six websites that were deemed “gold standard” sites by a breast cancer researcher and physician for their ability to provide accurate information easily and rapidly. All but one of the gold standard sites appeared in the top 30 of all four search engine results that were evaluated by the volunteers. Volunteers could rank the gold standard sites however they wanted. A couple of the gold standard sites received relatively low scores by some of the volunteers.
Xu and his fellow researchers categorized health-related websites in four ways: those that target the general population with basic information; nonprofit organization websites; corporation websites; and websites for professionals and researchers.
Google mostly generated websites meant for the general population, and those from nonprofit groups. Yahoo had overrepresentation in websites targeting the general population, while Bing represented general population websites as well as those meant for professionals. Ask.com results focused on nonprofit websites. Corporate websites were the least common across all four search engines.
Overall, Xu said, the Internet is a good thing for physicians and patients and can provide a lot of help to those looking for information. But users must view search engines like media sources, he said. The news and opinions you see expressed on Fox, for example, might be different from what is broadcast on CNN.
“It’s all controlled by the company,” Xu said. “It’s not just automatic.”