Hidden from consumers, patient medical data has become a multibillion-dollar worldwide trade between our health-care providers, drug companies, and a complex web of middlemen. This great medical-data bazaar sells copies of our prescriptions, hospital records, insurance claims, blood-test results, and more, stripped of names but still containing identifiers such as year of birth, gender, and doctor. As computing grows ever more sophisticated, patient dossiers are increasingly vulnerable to re-identification, which could make them a target for identity thieves or hackers. Paradoxically, comprehensive electronic files for patient treatment-a key reason medical data exists in the first place-remain an elusive goal. Even today, patients and their doctors rarely have easy access to full records that could improve care. In the evolution of medical data, the instinct for profit has outstripped patient needs. This book reveals the previously hidden story of how such a system evolved internation