The promise of the Internet is that answers to our questions are just a Web search and a few clicks away. Authors: Companies track website visits in ways that may compromise individuals private medical information. Confidentiality and privacy are important components of professional discussions about medical conditions, research and treatment. Authors say Google, Facebook, Twitter and Amazon are the biggest companies collecting the most health data, they say. No laws exist to meet the realities of how and whom medical information is exchanged, authors say.”]