Our results suggest children in capitated plans have patterns of outpatient utilization notable for greater use of urgent care and PCP-acute and well-child care, with lower odds of visits to EDs and specialty care. Although capitated enrollees had higher rates of overall outpatient utilization, regression analysis showed they were more likely to seek care in less costly locations (UC and PCP). In contrast, children in FFS plans were more likely to seek care at costlier sites (ED and specialty care).
Studies of disabled children and of adults found similar trends. Previous literature commented that disabled children in capitated plans had easier access to primary care and better coordination of emergency care, compared to those in FFS plans.(13, 14) Studies of adults in capitated plans, performed after the ACA in 2010 and the 2014 Medicaid expansion, reported lower rates of ED utilization and higher rates of PCP visits.(4, 24, 25) However, other reports noted a marginal increase(26, 27), or no change in rate of ED visits.(28) Recent years have seen increased enrollment in capitated MCOs, declining enrollment in FFS plans(29), but also declining enrollment of children overall(30). While longitudinal, nationwide studies of children are still warranted to ensure MCO payment models are indeed leading to cost-effective healthcare utilization, our data supports a trend of lower-cost sites of utilization by children with capitated MCOs. Policy makers and health systems should continue to support healthcare coverage of children and support programs that use capitated payment models with care coordination to improve timely access to lower-cost acute care settings for non-chronically ill children.
Our analysis also found that children in capitated plans had increased frequency of utilization (3, 4, or 5 + visits per year) of all acute care sites (ED, UC, PCP), compared to those in FFS plans. If children in capitated plans are high-frequency utilizers of healthcare, despite visiting lower-cost care settings (e.g. UC, PCP), the high volume of acute care visits may negate the financial benefit of capitated payment models. However, this trend of high acute care utilization by capitated enrollees may be a transient finding during a time of health insurance change. The phenomenon that pent-up demand plus increased access to healthcare leads to increased utilization was described among newly insured children after Oregon’s 2009–2010 CHIP expansion, and in adults after the 2014 Medicaid expansion under the ACA.(15, 31) Expansion programs that increase parents’ Medicaid eligibility (such as the 2014 Medicaid expansion and Oregon’s 2008 Medicaid expansion) have been associated with a ‘welcome mat’ effect on families, leading to increased enrollment in children.(32–34) Since these landmark changes in health insurance, children have had increased enrollment rates in Medicaid or CHIP, and likewise increased access to healthcare.(1) It’s unclear whether our finding of high acute care utilization by capitated enrollees reflects pent-up demand of newly insured children or a well-established medical home model in this cohort. This theory merits validation with longitudinal data.
Strategies on cost-containment based on site of healthcare delivery should focus on supporting the PCP even for FFS plans. However, when the PCP is not available, strategies to provide access to care at the most cost-effective site should be promoted. UC comprised a small portion of acute visits in both payment models, whereas ED visits were more common. Since UC offers cost-savings compared to similar ED visits, secondary cost-containment strategies may focus on shifting low acuity ED visits to UC. (18) The largest portion of acute care visits by children in capitated plans occurred at the PCP, and the smallest portion of acute care visits were to UC. This underscores the important role of PCPs in serving as the hub of the medical neighborhood, for children with acute or chronic illnesses.
Other explanations for high utilization for acute care visits in capitated plans, compared to FFS, may arise from influences other than that of the primary care provider. First, previous studies have shown that low-income families enrolled in health insurance plans with cost-sharing, compared to plans without cost-sharing, had decreased episodes of primary and emergency care, and reduced ambulatory expenses by up to one-third. (35, 36) The health implications of this reduction in acute care are not known currently. Cost-sharing still exists in Medicaid and CHIP but there is wide state-to-state variability in the structure of cost-sharing.(2) Second, minority races have been associated with some disparities in pediatric healthcare utilization, such as lack of a usual source of care prior to CHIP enrollment and receipt of fewer primary care services, while other studies show no healthcare disparities amongst race.(37, 38) Our study found a higher rate of minorities (Black, Hispanic, or Other) enrolled in capitated plans, compared to FFS, though it’s unclear whether race/ethnicity influenced utilization or these findings are an effect of baseline race/ethnicity disparities(37). Alternatively, the differences in races enrolled in the two payment plans may reflect state-level population characteristics and local availability of Medicaid payment models. The influences on patient behavior and healthcare utilization are complex and multi-factorial, and remain an ongoing area of research. Furthermore, utilization is merely one facet that contributes to the success of a payment model. Evaluation of current payment models must incorporate a multitude of factors beyond utilization, such as appropriateness of use, race/ethnicity influences, equitable access to health care, and health outcomes. Lastly, this cross-sectional, observational study does not determine causality related to the utilization patterns of children between the FFS and capitated groups. However, observable characteristics of the FFS group included more non-complex medical conditions. Therefore, if these characteristics would require increased medical attention, we would expect more acute care visits among FFS, rather than fewer. Nevertheless, this comprehensive, multi-state database offered rich information to characterize outpatient visits in the pediatric Medicaid population.
Limitations
Limitations of this study include generalizability arising from our choice to exclude children whose providers see exclusively one type of payment model (i.e. < 5 or > 95% capitation penetration rate), excluding > 2 million enrollees; however, this was necessary to alleviate the predominate of practice patterns within regions with a single payment model and made the sample population as comparable as possible. This exclusion reduces the generalizability of the results, as children in the final sample were likely less geographically diverse, were a higher percentage Black, had more chronic conditions, and had more utilization. A known limitation of Medicaid databases is the high turnover of enrollment. We included enrollees with > 11 months of continuous enrollment in order to capture a comprehensive view of outpatient visits in this cohort, consequently excluding another 1.2 million enrollees. The implications of a large number of enrollee exclusions is a potential bias of the outpatient utilization patterns noted in this study. Another limitation of de-identified US Medicaid databases is lack of state-specific Medicaid policies and lack of provider-level utilization (since claims are listed at the enrollee level), which limits our ability to draw conclusions or account for trends in utilization at the state or provider/practice level. A potential confounder that is not accounted for in this database includes urban versus rural geography of enrollees, or proximity of available in-network providers. If Medicaid managed care is more common in urban areas or has more available in-network providers, and urban dwellers have greater healthcare use and access(39), then geography differences may contribute to utilization disparities in this study. We controlled for high illness-severity by excluding disabled children or with complex chronic conditions, but given the constraints of this database we do not have a reliable means to quantify severity of disease in the remaining study population. As such it is possible that some of the differences in utilization we noted in this study are, in part, attributed to differences in severity of non-complex chronic conditions. While this study evaluates pediatric outpatient utilization, we are unable to draw conclusions on appropriateness of use, unmet needs, or health outcomes of these children. Finally, the rapidly changing climate of healthcare in the United States makes it difficult to predict whether the patterns from this single-year study will remain in the future.