Incentives to Encourage Primary Care Use: Results from a Randomized Controlled Trial

Purpose. Primary care is often promoted as a means to lower cost and improve patient outcomes through improved care coordination and prevention. However, few studies provide rigorous evidence to test this hypothesis. We conducted a randomized controlled trial, enrolling low-income uninsured adults, to determine whether cash incentives are effective at encouraging a primary care provider (PCP) visit, and if these visits result at lowering utilization and costs and improving patient-reported outcomes.

Study population. Subjects were enrolled through the large safety net program that provided access to primary care for uninsured subjects who had household incomes below 100% of the federal poverty level, had no other health insurance coverage, and resided within a 30-mile radius of the health center. Subjects were randomized to four groups: untreated controls, and one of three incentive arms with incentives of $0, $25, or $50 for visiting a PCP within six months of group assignment.

Methods. We used the exogenous variation generated by the experiment to obtain causal evidence on the effects of a PCP visit. We separate the analysis into the first six-month period (when PCP visits were incentivized), and the subsequent six months (post-incentive period); the latter period provides the cleanest evidence on how the earlier PCP visit (or the incentives) influenced utilization and costs. We then estimate 2SLS regressions to estimate the influence of PCP visits on utilization and costs. We estimate reduced for equations to determine the effect of PCP visits on patient-reported outcomes on PROMIS domains of anxiety, depression, and pain interference and general health.

Results. We observed modest reductions in non-urgent emergency department use and increased outpatient use, but no reductions in overall costs. These findings in utilization are consistent with the expectation that PCPs offer an alternative to the emergency department for non-emergent conditions. Total costs did not decline because any savings from avoiding the emergency department were offset by increased outpatient utilization.Improvements were observed for PROMIS domains for subjects randomized to the $50 group, presumably through their interaction with the health care system.

Conclusions. Using a rigorous study design and capitalizing on exogenous variation in the likelihood of an initial PCP visit, we show modest evidence that PCPs reduce non-emergent emergency department utilization in the short-term and may, in fact, initially increase costs. In the high health needs patients we study, in which nearly two-thirds report two or more chronic conditions, PCPs may have very little ability to reduce health care utilization in the short-term. Health status, among the very sick, may take years to improve, although we report initial improvements in anxiety, depression, pain interference, and general health. Cash incentives encourage PCP utilization but may also have unintended consequences for other types of health care utilization—outpatient care in particular. We conclude that although an initial PCP visit can be effectively incentivized, and patients have subsequent visits with the PCP, overall health care utilization may not be reduced, and may increase in the short-run.