What factors explain why the number of free clinics varies across urban communities

The nation's 47 million uninsured often delay or forego needed health care frequently because the cost of obtaining care is prohibitive. Uninsured patients may receive primary care at physician offices, health centers, public clinics, hospital outpatient departments, emergency rooms, and free clinics. Free clinics distinguish themselves by offering their care for free or for a nominal fee. Free clinics are a much more important component of the safety net than generally recognized. There are more than 1,000 known free clinics, which are estimated to serve 1.9 million patients and provide 3.2 million medical visits annually. The study objective is to determine whether unmet need explains why some communities have more free clinics than others. It represents the first known effort to explore the role of free clinics in the safety net. Numerous secondary data sources that describe all 361 U.S. metropolitan statistical areas were linked with an original data set of all known free clinics (n=1,007). Using an observational, cross-sectional design, a negative binomial model was fitted to estimate the effect of population characteristics, the capacity of the ambulatory safety net, and generosity of state Medicaid policies on the number of free clinics, controlling for population size, geographic region, and the cost of healthcare. Federally-qualified health centers (FQHCs) per 10,000 uninsured and FQHC “look-alikes” per 10,000 uninsured are negatively associated with the number of free clinics (IRR=.70 and IRR=.49, respectively; p<.05). Contrary to expectations, higher rates of uninsurance were associated with fewer free clinics (IRR=.00; p<.001). The number of free clinics is positively associated with Medicaid provider payment rates (IRR=1.87; p<.05). Free clinics fill in gaps left by the ambulatory safety net but do not respond to the neediest populations. Unmet need may be necessary, but is not sufficient, to explain free clinic growth and retention. Supply conditions likely play a prominent role. Medicaid provider reimbursement may be one mechanism to influence the availability of producers who are willing to supply free care. More adequate Medicaid reimbursement may increase a physician's willingness to provide charity care at free clinics. This study indicates a need to consider all sources of primary care, including free clinics, when assessing the adequacy of the ambulatory safety net. Given that charity care is declining, states that wish to encourage more charity care might succeed by increasing Medicaid provider reimbursement rates. Future research on the supply factors that influence free clinic formation is needed.