FDA Regulation and Early Prenatal Testing
Editors' note: The US Food and Drug Administration is currently considering regulation of laboratory developed tests (LDTs), which include noninvasive prenatal tests. The comment here was submitted to the FDA by George Estreich, as part of a comment period that closed on February 2. The FDA's materials on LDTs can be found here.
To the Food and Drug Administration:
I’m writing to urge the FDA to regulate the new, noninvasive prenatal tests, and I wish to focus particularly on health claims being made in the advertising for the tests. If prenatal testing is to be of greatest benefit both to individual women and to society at large, the information that accompanies that testing should be accurate, complete, useful, and most of all nondirective. The ads for NIPT do not meet these criteria. As a result, the advertising has a number of potential adverse consequences for consumers.
Beth Daley’s recent investigative report in the Boston Globe offers a disturbing look at the consequences of misinformation: as Daley notes, when both health professionals and patients believe that the test is “99% accurate,” as it is often advertised to be, both false positives and false negatives have serious consequences for prospective parents’ state of mind, and for the course of an intended pregnancy. Believing the test to be accurate, women have aborted healthy fetuses in the case of a false positive, or have carried fetuses with severe conditions to term.
These beliefs are mistaken, but they are completely understandable, given the expertly executed ads for the technology. Though the figure “99%” is ubiquitous in the ads, whether referring to sensitivity, specificity, or “accuracy,” the number of true interest to a consumer—the positive predictive value—is either in fine print, or difficult to find. As genetic counselor Katie Stoll has pointed out, the PPV—the chance that a positive is a true positive—ranges from around 50% accurate in the case of the most common conditions, to the single digits in the case of some of the microdeletion screenings now being offered. In some cases, the claim of accuracy is supported by the factually inaccurate claims that “fetal DNA” (or even “your baby’s DNA”) is tested directly. (It is placental DNA that is tested; the occasional mismatch between fetal and placental DNA likely accounts for false results.)
Misleading statistical claims are accompanied by powerful emotional appeals. The ads for NIPT are rife with images that provide emotional content, but no clinical information: beautiful pregnant women and chromosomally normal children. These images, along with risk-laden descriptions of the conditions to be avoided, establish an emotional, value-charged implicit argument for the test.
Indeed, even the name “noninvasive” is part of a coordinated marketing campaign. The companies contrast the test with amniocentesis and CVS, whose risks are repeatedly highlighted. And yet this approach may mislead. Since NIPS is not a diagnostic test, but a screening test, a positive result will require confirmation by invasive techniques. Therefore, it is troubling to see NIPS framed as an alternative. There’s a further danger too: in emphasizing the miscarriage risks of amnio and CVS, while presenting NIPS as accurate, the ads may discourage women from using the truly diagnostic test available to them.
In the ideal world, women would receive accurate, complete, and nondirective information to accompany a prenatal test. They would also have access to a genetic counselor or other expert health professional to help them interpret results. But the ads for NIPT are the opposite of this ideal: they are covert, using emotional appeals and misleading statistics; and they are, by definition, directive, in that their aim is to get consumers to opt for an expensive, proprietary test.
Because of the size of the market, the potential health consequences of this advertising are extensive. False results may lead to avoidable anxiety, and even to irreversible outcomes. In addition, the ads may undercut the relationship between healthcare provider and patient, requiring the provider to explain where the ads exaggerate. Regulating advertising for NIPS can therefore result in better outcomes for patients.
George Estreich received his M.F.A. in poetry from Cornell University. His first book, a collection of poems entitled Textbook Illustrations of the Human Body, won the Gorsline Prize from Cloudbank Books. His memoir about raising a daughter with Down syndrome, The Shape of the Eye, was published in SMU Press’ Medical Humanities Series. Praised by Abraham Verghese as “a poignant, beautifully written, and intensely moving memoir,” The Shape of the Eye was awarded the 2012 Oregon Book Award in Creative Nonfiction. Estreich lives in Oregon with his family.