There is no evidence that the tests Theranos offered are inaccurate. The company has voluntarily discontinued them to allow the FDA to review them [1].

The controversy is principally about Theranos claims about technology it has yet to deploy and the company's high valuation [2].

[1] http://www.azcentral.com/story/news/arizona/investigations/2...

[2] http://www.wsj.com/articles/theranos-has-struggled-with-bloo...