Table 2.
Study characteristics of newly identified studies in the updated systematic review.
| Main author, ref. (country) | Aim of the Study | Study Design (Response Rate) | Number & Type of Participant | Disease or type of DTC-GT identified |
|---|---|---|---|---|
| Bernhardt et al. [24] (USA) | “Assess PCPs’ current experience with genetic testing, their assessment of the understandability and clinical utility of information in sample direct-to-consumer reports for genomic assessment of disease risk and warfarin dosing and attitudes toward genomic medicine” | Quantitative: web-based survey with a small minority of open ended questions (23.30%) | 502 PCPs who are members of Knowledge Networks’ Physician Consulting Network (187 family medicine practitioners and 315 internal medicine physicians) | Various disease risks and warfarin dosing (pharmacogenetics) |
| Birmingham et al. [25] (USA)a | “To examine attitudes, knowledge, and behavioural intentions regarding genomic testing in relatives of men with PCa, and in providers.” | Mixed-method study: surveys and focus groups (N/A based on study design) | 24 providers (10 PCPs (8 primary care, 2 internal medicine) and 14 urologists or urology residents): recruited through either Huntsman Cancer Institute (n = 6), community urology practices (n = 8), and community practice clinics (n = 10). These 24 providers were divided into 5 focus groups. | Prostate Cancer |
| Burke et al. [26] (USA and Canada) | “To describe GCs testing strategies for patients who have already obtained DTC-GT results (23andMe) or TPI data (Promethease) that reported a BRCA1/2 pathogenic variant.” | Cross-sectional design: online survey (7%) | 80 genetic counsellors that were members of the National Society of Genetic Counsellors (reporting clinical cancer genetics as their primary specialty) | Breast and gynaecological cancer: BRCA1/2 |
| Carroll et al. [27] (Canada) | “To assess primary care providers’ experiences with, perceptions of, and desired role in personalised medicine, with a focus on cancer. | Qualitative study: focus groups (N/A (“purposeful sampling” used) | 51 primary care providers (30 family physicians, 11 registered nurses, 2 nurse practitioners, 1 physician assistant, 4 family medicine residents, 1 medical student, 2 not specified) | Non-specific DTC-GT |
| Carroll et al. [28] (Canada) | “To determine family physicians’ (FP) current involvement and confidence in GM, attitudes regarding its clinical value, suggestions for integration of GM into practice, and resources and education required.” | Quantitative: anonymous questionnaire (26% adjusted response rate) | 361 family physicians from the Scott’s Directory of Canadian physicians | Non-specific DTC-GT |
| Chambers et al. [21] (USA) | “The purpose of our study was to determine whether PCPs have improved in experience, confidence, and ability to order genetic testing since the recent surge of clinically relevant tests and well publicised rise and fall of affordable DTC genetic tests.” | Quantitative: surveys sent by mail (37.80%) | 310 PCPs: 204 family medicine physicians, 70 internal medicine physicians, 36 from other medical specialities | Non-specific DTC-GT |
| Haga et al. [29] (USA) | “Evaluated PCPs’ awareness of the role of genetics/genomics in health, knowledge about key concepts in genomic medicine, perception/attitudes towards direct-to-consumer (DTC) genetic testing, and their level of confidence/comfort in discussing testing with patients prior to and after undergoing DTC testing through the 23andMe Health+ Ancestry Service.” | Quantitative: web-based survey (<1%) | 130 registered PCPs (active physicians in the United States—facilitated by IQVIA, a health data science and clinical research company): 82 in family practice and 48 in internal medicine | Ancestry, health predisposition-genetic health risk, carrier status, traits and wellness |
| Howard and Borry [2] (Europe (28 Countries)) | To “present empirical evidence, both quantitative and qualitative, regarding the awareness of, experiences with, and attitudes towards DTC-GT services of clinical geneticists in Europe” | Mixed methods: online questionnaire (44% of the 300 institutions contacted) | 131 clinical geneticists from 28 different European countries | Pharmacogenomics, paternity, ancestry, carrier testing and disease testing i.e. breast, prostate cancer |
| Hsieh [30] (USA and Canada) | “This study seeks to explore the experiences, attitudes, and opinions of genetic counsellors in North America regarding DTC-GT and their willingness to see DTC-GT consumers in a clinical setting.” Secondly, to “report on the experience genetic counsellors have had interpreting DTC-GT results.” | Quantitative: survey distributed via mailing lists (12.20%) | 482 genetic counsellors (mailing lists associated with the National Society of Genetic Counsellors (NSGC) and the American Board of Genetic Counselling (ABGC) | Ancestry, paternity, traits, carrier screening, pharmacogenomics, adult-onset conditions and cancer. |
| Jonas et al. [31] (USA) | “To assess the degree to which direct-to-consumer genetic test results were being presented to physicians and identify genetics educational needs among physicians” | Quantitative: electronic survey (15%) | 1502 primary care and specialist physicians (Permanente Medical Group) | Health risk genetic testing and pharmacogenomics |
| Kalokairinou et al. [22] (Europe, 10 Countries))b | “To explore the experiences and attitudes of European clinical geneticists towards DTC genetic testing and its regulation”, “focusing on the experience of the participants with patients having undergone DTC-GT and their attitudes towards these tests” | Qualitative: semi-structured interviews (in person, via telephone or Skype) N/A based on study design | 15 clinical geneticists from 10 different European countries (Belgium, the Czech Republic, Finland, France, Ireland, the Netherlands, Slovenia, Sweden, Turkey and the UK) | Personal Genome Scans, carrier tests, nutrigenomics tests, pharmacogenomic tests, BRCA tests and whole exome sequencing |
| Kalokairinou et al. [23] (Europe (10 countries))b (same study as above) | “The attitudes of clinical geneticists towards the regulation of DTC genetic tests in Europe.” | Qualitative: semi-structured interviews (in person, via telephone or Skype) (N/A based on study design) | 15 clinical geneticists from 10 different European countries (Belgium, the Czech Republic, Finland, France, Ireland, the Netherlands, Slovenia, Sweden, Turkey and the UK) | Personal Genome Scans, carrier tests, nutrigenomics tests, pharmacogenomic tests, BRCA tests and whole exome sequencing |
| Kittikoon et al. [38] (Thailand) | “The primary objective of this study was to describe (a) awareness, (b) preparedness to provide counselling about the consumer-initiated genetic test, and (c) opinions on the usefulness of consumer-initiated genetic tests among physicians at an academic hospital in Bangkok, Thailand.” | Quantitative: paper questionnaires (60.20%) | 308 internal medicine physicians in an academic hospital in Bangkok, Thailand (223 residents, 14 fellows, and 71 faculty staff members) | Non-specific DTC-GT |
| Leighton et al. [32] (USA)a | “To investigate the general public’s perceptions and misperceptions about DTC genetic testing, as well as their ability to understand and interpret results…by surveying members of the general public, as well as genetic counsellors, who were used as a comparison group.” | Quantitative: online survey conducted on Facebook ((calculated & not reported - based on approximately 1500 GCs that were sent the survey) | 171 genetic counsellors (members of the National Society of Genetic Counsellors residing in the US) | Colon cancer, heart disease, basal cell carcinoma |
| Mainous et al. [33] (USA and Canada) | “The aims of this study are to elucidate academic family physicians’ perception of and experiences with clinical genetic testing and direct-to-consumer genetic testing, their self-assessed knowledge about currently available genetic tests, and how important they think genetic testing should be in the curriculum of medical students and residents.” | Quantitative: electronic survey (45.10%) | 1311 academic family physicians (still practicing)—members of the Council of Academic Family Medicine Educational Research Alliance (CERA) | Non-specific DTC-GT |
| McGrath et al. [34] (USA) | “To evaluate how [medical professionals] interpret genetic test results, determine their confidence and self-efficacy of interpreting genetic test results with patients, and capture their opinions and experiences with direct-to-consumer genetic tests (DTC-GT)” | Quantitative: online survey (9.10%) | 264 medical professionals divided into 2 categories: genetic specialists (Genetic Counsellor 61.0%, Clinical Geneticists 1.5%) & primary care providers (Internal Medicine 9.5%, Primary care (MD) 6.8%, Nurse Practitioner 6.1%, Family medicine (MD) 5.7%, Physician Assistant 5.3%, Emergency Medicine 1.9%, Other 2.3%,) | Genetic risk for diabetes, genomic sequencing for symptoms report implicating a potential HMN7B (distal hereditary motor neuropathy VIIB) diagnosis, and a statin-induced myopathy risk. |
| Ram et al. [37] (New Zealand) | “The aim of the study was to explore the attitudes of general practitioners (GPs) towards direct-to consumer (DTC) genetic testing and elicit their perceptions of the risks and benefits associated with DTC genetic testing.” | Mixed methods: questionnaire sent by post (38%) | 113 general practitioners registered with the New Zealand Medical Council | Non-specific DTC-GT |
| Salm et al. [36] (USA) | “This study explores neurologists’ and psychiatrists’ knowledge, attitudes, and practices concerning genetic tests.” | Quantitative: web-based survey, some clarifying free response questions (7.0% of psychiatrists, 7.5% of neurologists) | 372 psychiatrists and 163 neurologists | Non-specific DTC-GT |
| Unim et al. [35] (Canada)c | “The aim of this study is to identify genetic service delivery models, policies governing the use of genomics medicine, and measures to evaluate genetic services in the province of Quebec, Canada.” | Mixed methods: online questionnaire (18.75%) | 5 Physicians (16.7%) and 16 Genetic counsellors (53.3%) in a study with a total number of 30 participants | Breast CAncer genes 1 and 2 (BRCA1/2), Lynch syndrome, familial hypercholesterolaemia, inherited thrombophilia genetic tests |
aPapers with this symbol indicate studies that also involved participants other than HCPs (consumers/members of the general public) but for the purposes of this review, only findings related to HCPs will be included.
bThis study was a follow-up study to Howard et al. (2013) which is also part of this review.
cThis study had researchers (which were part of the exclusion criteria) representing 30% of the total number of participants (n = 9).