Google has announced that people looking for healthcare terms on its front page will now have the option to see a list of reviewed links, and sort their results by treatment or symptoms.

In Google Co-op, if users search for a particular symptom, illness or associated keyword on the main page of the site, they will be given the opportunity to refine their results. When certain health-related words (eg. ‘pain’) are inputted into Google’s search box, a "Refine results" option appears.

Users can look at the results according to treatment, research papers, symptoms, news, or alternative medicine and sort them by medical establishment. Google Co-op relies on a free-to-join community of users and professionals to categorise the results, and organisations such as the Health on the Net Foundation and the National Library of Medicine. Users can also choose from whom they get their results.

An accompanying press statement by Google, released at Wednesday’s annual press day, explained: "A doctor can label web pages related to arthritis, and users who subscribe to that doctor’s information will receive options at the top of the results for more specific information such as "treatment," "symptoms," or "for health professionals" when they enter a relevant query.

"As a first step, Google has worked with partners to annotate web pages related to health and city guides and to offer dozens of subscribed links to specialized content such as restaurant and movie information.

"Going forward, the broader online community will begin building out new topic areas and subscribed links to help improve the way people find and discover information online."

Rumours were rife before they announced the service that Google were going to launch a health-specific search tool. Blog SearchEngineWatch reported that some functionality on Google already appeared to be live at the beginning of the week.

Industry analysts started talking about Google Health when’s Google blog noticed that an employee of the search engine attended a conference with the job title ‘Architect, Google Health’.

News of the health results clustering came after an editorial in the British Medical Journal, written by a senior medical librarian, called for a medicine search engine that pointed patients and doctors towards best evidence on health matters.

Dean Guistini, from the University of British Columbia, Canada, wrote: "Call it Google Medicine; design an interface with medical filters and better algorithms; lead to the best evidence (just don’t forget to consult with librarians about where the evidence is located). This kind of all-purpose tool is badly needed in medicine, particularly for developing countries."

Guistini told E-Health Insider that Google Medicine was still necessary, because information needed to be presented in context. Ideally the search should be done in a separate channel from the main site.

"Does it make sense to search across the *entire* Internet and all 50 billion pages for medical information, when the wheat should be searched apart from the chaff?" he said. "From a librarian’s perspective this is ill-conceived and a waste of time. Information demands classification. Computer power cannot replace organisation."

There have been several studies undertaken on patients’ use of the internet and Google in particular in searching for health information. A study of nearly 6,400 adult Americans published in the Archives of Internal Medicine showed the internet was the first port of call for healthcare information for 48.6% of people, as opposed to 10.9% for GPs.

Google Co-op has been made available on all English language pages. As well as healthcare, it features city guides, computer games and cars.