Physicians' General Attitudes to Genomic Testing
Several physician surveys have been recently conducted to address the question of physicians' perceived utility of genomic testing. In 2008, Scheuner et al. published a systematic review examining the delivery of genomic testing for common chronic diseases. This systematic review identified numerous studies citing generally positive attitudes among physicians regarding the perceived clinical benefits of genomic testing. However, the study highlighted limitations in physician understanding of genomic medicine, including knowledge gaps among physicians regarding genetic and genomic testing for common chronic diseases. It raised concerns about privacy and discrimination as a common barrier identified across multiple physician surveys. The study also described challenges in integrating genomic testing into primary care practice, including the discrepancy between the medical workforce available and that needed for the growth of genomic medicine.
Since this systematic review, there have been several important studies of physicians' use of and attitudes regarding genomic testing. Two physician surveys, one of primary care physicians and the other of generalists and specialists at two academic medical centers, cataloged the current clinical use of genetic tests and found intermittent testing for monogenic disorders such as Factor V Leiden for venous thromboembolism risk or BRCA1/2 for breast cancer but rare use of genomic testing of any kind. Using the model of Type 2 diabetes, Grant et al. conducted a national survey of general internists and endocrinologists to assess physicians' perceptions of the clinical utility of genomic testing for common chronic disease. In that study, most physicians reported 'Somewhat' or 'Very' positive opinions of genetic testing and would recommend a genomic test to a patient, and 47% of physicians were 'Very likely' to recommend a genomic test directed at optimizing diabetes medication. Similarly, in a nationally representative survey of approximately 500 US primary care physicians regarding DTC testing, Bernhardt et al. found that 40% of respondents agreed or strongly agreed with the statement: "At this time, genetic testing for risk for common diseases offers information that is clinically useful." More telling was that 40% of respondents neither agreed nor disagreed with the statement, suggesting uncertainty in their opinions.
In 2011, Powell et al. conducted a survey of physicians' knowledge and attitudes regarding DTC testing among 382 primary care providers in North Carolina and found that a minority of survey respondents (38%) were aware of DTC genetic testing, and only 15% were prepared to discuss DTC testing with patients. Among those who reported awareness of DTC testing, approximately 40% believed that it was clinically useful, comparable to the findings of Bernhardt et al. described above. The views of physicians and genetic counselors towards DTC testing were recently reviewed by Goldsmith et al.; studies in the USA, Japan and Greece showed variable physician awareness of DTC but generally positive views of its usefulness among those who were aware. Although focusing more on genetic instead of genomic testing, Mainous et al. found similar results. In their survey of 1311 family physicians in Canada and the USA, approximately 70% of physicians believed genetic testing was at least 'Somewhat valuable' in primary care, regardless of whether they self-reported as 'Somewhat or very knowledgeable' or 'Not knowledgeable' about genetic testing. Using semistructured interviews to assess behavioral beliefs regarding genomic testing among primary care and specialist providers at a Veterans Health Administration clinic in Texas, USA, Arar et al. found that all 20 providers studied felt that genomic testing would be valuable in clinical medicine. This positivity is reflected in other recent surveys that have reproducibly found that 40–60% of physicians, again spanning primary care providers and specialists, believe genomic testing will have value in clinical practice.[13,19]
Another interesting finding is a physician perception that genomic testing will be of greater utility in the near future. In the Bernhardt and Mainous studies, 50% and 70–80% of primary care and family practitioners, respectively, believed that genomic testing will be clinically useful in 5 to 10 years.[12,17] This anticipated increase in the clinical utility of genomic medicine could reflect an acknowledgement of the progress in genomic discovery. That the perceived utility of genomic medicine is not higher at present may reflect the realistic understanding that its clinical integration will depend on its ability to contribute to improved patient care and on the ability of health systems to adopt it.
The Grant et al. study described above formulated a general framework for the clinical utility that genomic testing might have in three domains: risk prediction and its consequences for clinical management, motivating behavior change, and guiding pharmacotherapy. This framework is useful for evaluating more recent studies of the perceptions physicians have of the clinical utility of genomic testing. Below we describe the literature on physicians' attitudes and perceptions of genomic testing in each of these three domains.
Personalized Medicine. 2014;11(4):425-433. © 2014 Future Medicine Ltd.