The internet search engine, Google, needs to maintain better control of its advertisements and suggested links in order to avoid web pages that contain worrying medical claims, doctors have warned.

The doctors from the University of Florence in Italy used Google Italia to search under the keyword ‘aloe’. They found sponsored links to websites recommending aloe products for sale, which claimed to prevent and treat cancer.

Writing in the British Medical Journal, the doctors explained that AdWords is ‘Google’s flagship advertising product’ and was its ‘main source of revenue in 2007’.

Through it, users can create advertisements, choose their own key words, and decide which Google queries their advertisements should match. Google decides on placement on its pages of search results - which advertisements to show and in what order.

However Google’s automated matching to search terms sometimes places inappropriate advertisements.

For example Google Guide (which is neither affiliated with nor endorsed by Google), says that in September of 2003, ‘adjacent to a New York Post article about a gruesome murder in which the victim’s body parts were stashed in a suitcase, Google listed an ad for suitcases. Since that incident, Google has improved its filters and automatically pulls ads from pages with disturbing content’.

However the Italian doctors noted that Google’s automated matching to search terms sometimes places inappropriate advertisements and argued that the site’s filters must be improved further.

“Google has often said that it wishes to enter the healthcare arena in many ways. We think that a necessary first step for Google is to improve its filters and algorithms so as to prevent possible harm to its users,” they said.