Impact of Retail Medicine on Standard Costs in Primary Care: A Semiparametric Analysis James E. Rohrer, Ph.D., Kurt B. Angstman, M.D., and Gregory A. Bartel, M.D. Abstract Retail medicine clinics have become widely available. However, few studies have been published that compare retail clinic costs of care to standard medical visits for similar patients. The purpose of this study was to compare standard medical costs during a 6-month period after visiting a retail medical clinic to care received in a conventional medical office setting. Medical records of primary care patients (both adults and children) seen in a large group practice in Minnesota in 2008 were analyzed for this study. Two groups of patients were studied: those who used a retail walk-in clinic (N ¼ 141) and a comparison group who used regular office care for same-day, acute visits (N ¼ 137). Patients treated for 5 common conditions (pink eye, sore throat, viral illness, bronchitis, and cough) were selected. The dependent variables were standard costs using federal rates and the rank of standard costs. Multiple linear regression analysis was used to adjust for differences between groups. Median costs did not differ between sites ($126.30 for usual care and $88.10 for retail, P ¼ 0.139); mean cost ranks were 132.5 for usual care and 115.6 for retail (P ¼ 0.088). After adjusting for previous visit history, age, and sex, patients who received care in the retail setting had lower standard costs and lower cost rank than patients who received usual care (b ¼52.9 [P ¼ 0.006] and b ¼24.5 [P ¼ 0.021], respectively). After selection of cases with common conditions and adjustment for unequal variances, age, sex, and number of office visits in the previous 6 months, our retail clinic appeared to reduce medical costs for patients during the 6-month period after the index visit. (Population Health Management 2009;12:333–335) Introduction I n the United States, medical care systems struggle to keep medical care production costs at or below federal reimbursement rates. Some health care reform proposals, if enacted, would bring an even larger fraction of the patient population into public sector insurance plans. As medical care system managers search for ways to increase access and control costs without harming quality, retail walk-in clinics are being opened across the nation. 1–3 These clinics are pro- moted as offering a more convenient 4 and less costly alter- native to standard medical practice for common medical problems, while not supplanting the medical home, and as providing care that meets quality standards. 5,6 Furthermore, because of its superior accessibility, retail care may be able to reduce disparities in access to medical care. 7 Nevertheless, retail clinics are controversial because they rely heavily on mid-level providers, such as nurse practitioners and physician assistants, who do not develop primary care relationships with retail clinic patients. They are supervised by physicians, but this supervision usually is not on-site. Nontraditional care could increase the cost of medical care if it increases the need for follow-up visits. Failure to resolve problems could result in duplication of some visits with a physician in the standard clinic or even lead to avoidable emergency room visits. Cost comparisons are difficult, however, because the billing rates differ among clinics. For- tunately, standard fees paid by the Centers for Medicare and Medicaid Services (CMS) are published online. The purpose of this study is to test the theory that retail visits lower downstream costs compared to standard care (provided in a same-day acute medical clinic) for the simple acute conditions that these clinics are designed to address. A competing theory is that costs are higher after retail visits because these clinics are less effective at resolving problems. Methods Medical records were abstracted for 2 cohorts of patients: the first group of patients was seen in a new retail walk-in clinic, and a comparison cohort of patients was seen in a standard same-day acute medical clinic. Cases were limited Department of Family Medicine, Mayo Clinic-Rochester, Rochester, Minnesota. POPULATION HEALTH MANAGEMENT Volume 12, Number 6, 2009 ª Mary Ann Liebert, Inc. DOI: 10.1089=pop.2009.0007 333