The Controversy of Direct to Consumer Lab Testing: What it Means to Patients
Increasingly, patients are turning towards non-traditional health care sites, such as retail stores, pharmacies and virtual/telemedicine. As consumers shoulder more of their health care costs, they are choosing care with an eye on costs. Direct to consumer lab testing as a result is flourishing.
Theranos, a company that provides direct to consumer testing based on a proprietary finger prick method, has been the subject of recent intense scrutiny due to their lack of transparency of the technology and unwillingness to participate in independent peer review and regulatory accreditation. In order to assess the accuracy of the Theranos platform, a study was conducted comparing results to conventional venipuncture.
The study included collecting 14 samples per subject for 22 clinical lab measurements per sample for 60 subjects. Tests were sent to Theranos, LabCorp and Quest Diagnostics. The following tests were performed:
CBC with differential
Lipid panel: cholesterol, LDL, HDL, triglycerides
Theranos samples had had higher sample rejection rates (12.5 times more likely). Theranos reported more results outside their normal range (1.6 times more likely). This is important in that it can lead to repeat testing, inconvenience, increased cost and delay in care or potentially inappropriate care. Theranos reported systematic biases toward lower test values for all 3 cholesterol components. However some measures did agree (e.g., triglycerides and rbc counts), whereas others differed significantly (e.g., wbc counts, mean corpuscular volume [MCV], cholesterol, high-density lipoprotein cholesterol [HDL-C]).
What it means to patients
Inaccurate lipid results might lead providers to either inappropriately initiate or fail to appropriately initiate statin therapy. Healthcare decisions and outcomes are vitally dependent on lab results.
This study sheds light on the importance of the need for transparency in lab testing. As a consumer, ask where your labs are being performed. Is the lab accredited by the College of American Pathologists or a similar national agency? Only then you will know that the lab performs quality testing with precise and accurate results.
Low volume sample testing such as that offered by Theranos has innate problems with accuracy and precision. Further testing in an open and transparent manner is required to refine the technique.