Most patients who participated in multiplex genetic susceptibility testing recalled their results correctly, did not interpret results in an overly deterministic way, and appreciated that genetics and behavior both contribute to disease risk. These results are consistent with national surveys indicating that only 25–33% of the public holds deterministic beliefs about genetic causation of disease.29,30
It is noteworthy that few testers reported having talked with their health care providers about the results up to three months after receiving test feedback. This may be a function of the time interval. It may also be attributed to their minimal emotional responses to results, a finding consistent with existing research in the context of other genetic susceptibility testing.31–34
A recent study conducted in a preventive medicine clinic showed only modest effects on disease risk perception and worry, which attenuated over time.35
While our study materials indicated that we would not share test results with their provider, patients may have been concerned about privacy and potential discrimination should discussions of test results with their provider be entered into the medical record. Our findings also suggest that there may be considerable differences in provider and patient perceptions of the frequency of DTC test discussions, a finding that warrants further exploration.
Several features of the Multiplex Initiative must be considered in interpreting these results. We relied upon best practices in clear health communication and health literacy16,17
in developing test feedback materials, and other DTC feedback materials may be substantively different. Patients’ responses to DTC test results are likely to differ substantially based on the content of test feedback. Our prior work evaluating 29 health-related DTC websites indicated wide variability in the quality of informational content, showing gaps in information about test limitations and little use of explanations for technical terms.36
In addition, the results of a recent Facebook survey of 141 members of the general public indicated the potential for misinterpretation of DTC test results.37
This prior research therefore suggests that patients will have different outcomes to DTC test results generated by different sources. One specific area in which patient responses may differ is related to genetic non-determinism. Our test feedback emphasized the role of health habits in the causation of the health conditions on the Multiplex test, which may have led, at least in part, to the finding that patients did not interpret the results in an overly deterministic way. However, if test feedback from DTC companies focuses only on the role of genes in disease causation, patients might have a more deterministic interpretation of their results.
While our sample was drawn randomly from a large insured population, like most early adopters of health innovations, those who sought genetic testing had higher educational levels than the underlying patient population.14
The Multiplex test assayed only 15 genetic variants, whereas current DTC tests that include far larger numbers of variants may be more difficult to comprehend fully, particularly in the instance of pleiotropy. One recent study indicated that recall was low for 14 participants with advanced training in genetics who underwent genomic profiling.38
Considered together, it is likely that our results underestimate the proportion of individuals who might be confused by multiplex genetic tests results. Indeed, if as forecast DTC tests become less costly and more broadly available, misinterpretation and confusion likely will occur among some target groups and providers would be credible sources of information to reduce such misunderstandings.
Our results indicated that a more deterministic interpretation was associated with testers being confused by the information, having lower educational attainment, and being members of racial and ethnic minority groups. Additional prior research has shown that having limited educational attainment or being members of racial and ethnic minority groups with experiences of discrimination may influence interpretation of genetic test feedback.6,39
Providers could use brief screening questions (e.g., “What could you do to lower your chance of getting those health conditions?”) to identify patients who may be misinterpreting results from genetic susceptibility testing. Patients whose responses suggest deterministic interpretations or other misconceptions could benefit from providers re-emphasizing that while our current knowledge indicates that genes slightly increase susceptibility for common health conditions like adult onset diabetes, health habits currently are the best predictors of disease risk.
While our data does not lend insight into the expectations of patients who discussed test results with providers, prior research suggests that such patients may expect the provider to take the results into account when providing care, despite their lack of clinical validity and utility.13
Additionally, qualitative reports indicate that patients can be frustrated when providers disregard results or actively denigrate DTC tests.40
Our prior work indicated that those patients who seek testing tend to be highly motivated to change health habits.13
Thus, providers could take advantage of patients’ interest in their disease risk as a teachable moment to promote engagement in evidence-based health behavior change programs that can reduce risk. For health care providers asked to respond to DTC genetic susceptibility test results, augmenting these results with a comprehensive family history assessment may also be advised.41
Despite the unique features of the Multiplex Initiative, our findings lend insight into challenges and opportunities for patients and providers as DTC testing becomes more widely available. At a time of considerable debate of regulation about DTC genetic testing, these findings begin to suggest that using evidence-based communication strategies with patient populations about the limits of genetic testing can do two things: (1) result in accurate interpretation of risk associated with common gene variants for the majority of patients and (2) minimize impact on scarce provider visit time. Going forward, it is critical to examine the impact of DTC genetic information on provider-patient interactions, particularly if patients are being tested but not seeking out follow-up advice from health care providers. In addition, as providers engage with patients about genetic susceptibility test results, either at the patients’ or providers’ initiative, there will be a growing need for strategies providers can use in the context of short health visits to address patient needs. Concerns about health care providers’ competencies to interpret and apply genetic information in practice have been a major thread in the debate about DTC availability of genetic susceptibility tests.6,42,43
To maximize the potential benefit of genetic susceptibility information for patients’ health, it is critical for health care providers to be aware of potential areas of misinterpretation of results and gain skills needed to maximize the benefit of these interactions to promote the health and well-being of their patients.