WASHINGTON (Reuters) - Web sites offering a sense of community to people with diseases or ailments often are created by marketers who fail to disclose that they are sharing data about site users, a complaint filed with U.S. regulators charged on Tuesday.
Four pro-privacy groups filed a complaint with the Federal Trade Commission, detailing a number of techniques that marketers use to identify people who are potential purchasers of particular medications.
For example, advertisers collect data on consumers' health worries by noting what web sites they visit and what searches they do, the report said.
Marketers also create web sites to build a community of people with the same health problems, and then collect information about them without specifically disclosing that fact.
"I thought the unbranded web sites were really disturbing," said Jeffrey Chester, chief researcher and head of the Center for Digital Democracy. "You think you're on an impartial site but you're not."
His group filed the complaint, along with the US Public Interest Research Group, the World Privacy Forum and Consumer Watchdog.
Alliance Health Networks was among those cited in the complaint. It hosts web sites linked to diabetes, arthritis, depression and 15 other ailments or concerns where people with those diseases share information and cheer each other on.
A Reuters check of the company overview on its website indicates marketers can benefit: "The company's interactive health networks deliver a unique value proposition to consumers and health marketers alike."
The complaint had similar concerns about a long list of other websites that discuss ailments but do not disclose relationships with advertisers or drug companies.
"It's unfair and deceptive if they're (Internet users) not told that tremendous amounts of data is collected about them," said Chester.
The FTC, which is due to release a privacy report within weeks, did not return telephone calls seeking comment.
A spokesman for Alliance Health had no immediate comment.
(Reporting by Diane Bartz; Editing by Tim Dobbyn)