How Redefining a Test’s Clinical Utility Threatens Patient Care
Elaine Lyon, PhD, collaborated with other experts in oncology and genetics in publishing a journal article that cautions and brings attention to the new definition regarding the clinical utility of tests.
Imagine a straightjacket’s snug fit around the clinical utility (CU) of each laboratory test. CU refers to the benefits of a test for each patient. In a recent article in the Journal of Molecular Diagnostics, a group of pathology experts teamed up to emphasize the robust and varying roles inherent in a test’s CU and to challenge the restrictive “fit” of a new definition that some payers (e.g., insurance companies, Medicaid) are promoting.
Some payers want to redefine CU for molecular diagnostics as “demonstrated improved patient outcomes” similar to drug-therapy studies. Elaine Lyon, PhD, an ARUP Laboratories medical director and senior author of the paper mentioned above, points out that such clinical trials are not practical for diagnostic tests (i.e., do patients who receive an accurate diagnosis have better outcomes than those who do not have a diagnosis?) or could take years to arrive at results; in the meantime, the restrictive definition excludes people who may need the test (the control group) from receiving it and overlooks the various reasons a physician would order a given test.
There needs to be a model that moves toward, not away from, patient-centered care. The goal of precision medicine is at risk here if we do not allow for all the ways results can be useful.
Elaine Lyon, Medical Director, Molecular Genetics and Genomics & Co-Medical Director, Pharmacogenomics, ARUP Laboratories
“One test can be used for different purposes. Insisting on clinical studies that only focus on one purpose to demonstrate CU ignores other uses or reasons why a physician may order the test,” points out Lyon, who oversees ARUP’s Molecular Genetics Lab sections. A test may be ordered due to a patient’s symptoms to aid in diagnosing, because of family history, or to predict disease course. “It goes beyond just determining what medication and dosage to provide.”
For example, if a patient with breast cancer tests negative for BRCA 1 / 2, the physician may move forward with treatment (specific drug therapies) based on this information; however, the very same test may be used for someone who doesn’t have breast cancer but is being tested because there is a strong family history of breast cancer. In this case, the test is used as a screening tool. “The differing reasons for ordering a test and the varying treatment pathways do not fit into one ‘demonstrated improved outcomes’ model,” says Lyon. “It is very difficult for a lab to perform clinical trials to show improved outcomes when a lab result is only an intermediate step. It really depends on how the physician uses the information.”
The paper evolved from an Association for Molecular Pathology task force known as the “Framework for the Evidence Needed to Demonstrate Clinical Utility.” All members/co-authors have expertise in oncology and genetics.
While precision medicine is driving healthcare progress today, according to Lyon and her colleagues, this restricted definition of clinical utility is putting the brakes on such progress. “There needs to be a model that moves toward, not away from, patient-centered care,” says Lyon. “The goal of precision medicine is at risk here if we do not allow for all the ways results can be useful.”