[cowsandmilk]

exactly, the dilution of samples needs to move to the forefront of the discussion.

Theranos:

(1) takes a much smaller amount of blood, claiming they will use the Edison machine to analyze it

(2)(a) sometimes uses the Edison machine, whose accuracy is disputed

(2)(b) sometimes dilutes the sample to test using a regular machine. The dilution moves normal concentrations outside the range of detection of the machine, so when a 10x dilution has its concentration multiplied by 10, there are huge errors, often causing misdiagnosis

When Theranos receives a proficiency test, they don't receive a small amount of blood. They receive the amount of blood a normal lab receives. These are the only samples that they can run in the manner the standard machines were designed for.

Theranos competes on costing less and taking less blood. The doubts are all around whether you can get accurate results with smaller amounts of blood from a different body part.

[abb1234etric]

This seems to me to be the most premise summary of what likely happened. Startup raises a ton of money for a new model that isn't ready yet.. so they use existing machines to fake it till they figure out how to get the Edison machine to work. Not terribly dissimilar in some way from jet.com just buying goods you ordered off of other sites and paying for the difference, in hopes they can test the market, build a brand and eventually make their model work. Problem is that it isn't obvious that scale helps you reach the ultimate goal here (unless you reason that more money/longer runway = higher likelihood of success). Unfortunately for Theranos, actual lives are at stake here and there is a lot of regulation in the medical space for good reason.