Subjects: Quality and safety
In letters to thousands of physicians that cared for at least one affected patient, Quest Diagnostics has acknowledged providing incorrect results on Vitamin D tests carried out at its facilities between early 2007 and mid-2008.
Company spokespeople indicated the problem affected less than 10% of all Vitamin D tests done during the period, and that the problem has been resolved. The company is offering free do-overs for affected patients.
Most of the errors involved overstating the true Vitamin D level, which could mean that some patients did not receive supplements as they should have, according to the New York Times.
Michel edits the Dark Report, a newsletter that broke the story.
The inaccuracies came after Quest shifted to a new Vitamin D assay that relied on mass spectroscopy. The new test had been adopted to improve accuracy and offer more information.
Wael Salameh, a medical director for endocrinology at Quest traced the problem to faulty materials used to calibrate the spectroscopes and to occasional failures to follow proper calibration procedures.
In recent years, Vitamin D testing has surged in response to studies showing that deficiencies of the fat-soluble vitamin are more widespread than had been thought, and are associated with increased risk of bone disease, immune deficiencies, cancer and cardiovascular disease.