Running large batteries of medical tests on people is not an undisputed public good. False positives abound, and without a clear idea as to why we want the test information and what we plan to do with it, bad outcomes can result.
Professor Norman Paradis of the Dartmouth College medical school has also questioned not just the claim that Theranos can produce cheaper, faster, less scary blood tests, but also the assumption that succeeding in this quest would improve public health.
In a piece titled, The Rise and Fall of Theranos, which ran in Scientific American and the online magazine The Conversation, he questioned the value of the Theranos promise to run dozens of tests on a small amount of blood. “From a clinical perspective, this was always concerning, as such a shotgun approach to medical testing is actually very bad medicine.”
It’s not that he’s against blood tests in the right context. “I’m very big on ordering tests,” he said. “But I don’t immediately say we need to start treatments.” What’s needed for better preventive medicine isn’t just more tests, but more accurate tests, and a better understanding of what to do with the results.
If any good comes out of all this, said pathologist Master, it would be a better understanding of the need for thoughtful interpretation followed by careful decision making. “Medicine,” he said, “is more than getting a number out of a box.” (Source)
Testing (and resulting personalization of treatment) must be embedded in a context. In medicine, that testing is usually undertaken to confirm or deny hypotheses, and to look for generally expected problems that occur across populations (e.g. cholesterol testing).
When testing becomes cheaper, there is often an idea that we can now test before we detect or suspect problems. But as a basic familiarity with the Base Rate Fallacy will show you, increasing the variety of things we test for dramatically decreases the specificity of the results. See Sensitivity vs. Specificity