Differential use of available genetic tests among primary care physicians in the United States: results of a national survey

Purpose: This study assesses primary care physicians' experience ordering and referring patients for genetic testing, and whether minority-serving physicians are less likely than those serving fewer minorities to offer such services. Methods: Survey of a random sample of 2000 primary care physicians in the United States (n = 1120, 62.3% response rate based on eligible respondents) conducted in 2002 to assess what proportion have (1) ever ordered a genetic test in general or for select conditions; (2) ever referred a patient for genetic testing to a genetics center or counselor, a specialist, a clinical research trial, or to any site of care. Results: Nationally, 60% of primary care physicians have ordered a genetic test and 74% have referred a patient for genetic testing. Approximately 62% of physicians have referred a patient for genetic testing to a genetics center/counselor or to a specialist, and 17% to a clinical trial. Minority-serving physicians were significantly less likely to have ever ordered a genetic test for breast cancer, colorectal cancer, or Huntington disease, or to have ever referred a patient for genetic testing relative to those serving fewer minorities. Conclusions: Reduced utilization of genetic tests/referrals among minority-serving physicians emphasizes the importance of tracking the diffusion of genomic medicine and assessing the potential impact on health disparities.