The book: When people think “big data,” they often think of information being mined from social media usage and Internet browsing histories. What many consumers don’t know, however, is that their medical data are also being sold in a multibillion-dollar marketplace with players ranging from doctors to insurance providers to drug companies. All these data are stripped of names before being sold, but as computing power continues to grow, the risk of re-identification using information such as birth year, gender, and partial zip codes also increases, carrying with it the possibility of medical identity theft and other serious consequences.

In Our Bodies, Our Data: How Companies Make Billions Selling Our Medical Records (Beacon Press), Adam Tanner *88 delves into the world of medical data, tracing the industry’s evolution from its start in the 1950s with the founding of IMS Health, the world’s dominant health-data miner, to now. The digitization of medical data has long been touted as a way to revolutionize treatment by facilitating breakthroughs in research and giving patients easy access to their medical records. Tanner also examines how that promise has panned out.

The author: Adam Tanner is a fellow at Harvard University’s Institute for Quantitative Social Science and is also the author of What Stays in Vegas: The World of Personal Data–Lifeblood of Big Business–and the End of Privacy as We Know It (PublicAffairs).

Opening lines: “Soon after you tell your doctor about an intimate medical problem, data about your condition are sold commercially to companies that have nothing to do with your treatment or billing. The electronic medical record company may sell information about your embarrassing problem that the physician logs into the computer. The lab performing the blood test often sells a copy of the results. The pharmacy receives money for sharing the details of your prescribed medications, as does the insurer covering the cost of your treatment.”

Reviews: Kirkus Reviews says, “A thorough report, carefully researched and well-documented, aimed at both general readers and policymakers.”