Medicaid Managed Care Enrollees Research Articles

Effects of Early Dual-Eligible Special Needs Plans on Health Expenditure.

To examine the effects of the penetration of dual-eligible special needs plans (D-SNPs) on health care spending. Secondary state-level panel data from Medicare-Medicaid Linked Enrollee Analytic Data Source (MMLEADS) public use file and Special Needs Plan Comprehensive Reports, Area Health Resource Files, and Medicaid Managed Care Enrollment Report between 2007 and 2011. A difference-in-difference strategy that adjusts for dual-eligibles' demographic and socioeconomic characteristics, state health resources, beneficiaries' health risk factors, Medicare/Medicaid enrollment, and state- and year-fixed effects. Data from MMLEADS were summarized from Centers for Medicare and Medicaid Services (CMS)'s Chronic Conditions Data Warehouse, which contains 100 percent of Medicare enrollment data, claims for beneficiaries who are enrolled in the fee-for-service (FFS) program, and Medicaid Analytic Extract files. The MMLEADS public use file also includes payment information for managed care. Data in Special Needs Plan Comprehensive Reports were from CMS's Health Plan Management System. Results indicate that D-SNPs penetration was associated with reduced Medicare spending per dual-eligible beneficiary. Specifically, a 1 percent increase in D-SNPs penetration was associated with 0.2 percent reduction in Medicare spending per beneficiary. We found no association between D-SNPs penetration and Medicaid or total spending. Involving Medicaid services in D-SNPs may be crucial to improve coordination between Medicare and Medicaid programs and control Medicaid spending among dual-eligible beneficiaries. Starting from 2013, D-SNPs were mandated to have contracts with state Medicaid agencies. This change may introduce new effects of D-SNPs on health care spending. More research is needed to examine the impact of D-SNPs on dual-eligible spending.

Medicaid Managed Care Structures and Care Coordination.

Child enrollment in Medicaid managed care (MMC) has expanded dramatically, primarily through state mandates. Care coordination is a key metric in MMC evaluation because it drives much of the proposed cost savings and may be associated with improved health outcomes and utilization. We evaluated the relationships between enrollment in 2 MMC structures, primary care case management (PCCM) and health maintenance organization (HMO) and access to and receipt of care coordination by children. Using data from the 2011/2012 National Survey of Children's Health and the Medicaid Statistical Information System state data mart, we conducted a retrospective, cross-sectional analysis of the relationships between fee-for-service, PCCM or HMO enrollment, and access to and receipt of care coordination. State-level univariate analyses and individual and state multilevel multivariable analyses evaluated correlations between MMC enrollment and care coordination, controlling for demographic characteristics and state financing levels. In univariate and multilevel multivariable analyses, the PCCM penetration rate was significantly associated with increased access to care coordination (adjusted odds ratio: 1.23, P = .034) and receipt of care coordination (adjusted odds ratio: 1.37, P = .02). The HMO penetration rate was significantly associated with lower access to care coordination (adjusted odds ratio: 0.85, P = .05) and receipt of care coordination (adjusted odds ratio: 0.71, P < .001). Fee-for-service served as the referent. State utilization of MMC varied widely. These data suggest that care coordination may be more effective in PCCM than HMO structures. States should consider care coordination outcomes when structuring their Medicaid programs.

Association of State Access Standards With Accessibility to Specialists for Medicaid Managed Care Enrollees

Medicaid recipients have consistently reported less timely access to specialists than patients with other types of coverage. By 2018, state Medicaid agencies will be required by the Center for Medicare and Medicaid Services (CMS) to enact time and distance standards for managed care organizations to ensure an adequate supply of specialist physicians for enrollees; however, there have been no published studies of whether these policies have significant effects on access to specialty care. To compare ratings of access to specialists for adult Medicaid and commercial enrollees before and after the implementation of specialty access standards. We used Consumer Assessment of Healthcare Providers and Systems survey data to conduct a quasiexperimental difference-in-differences (DID) analysis of 20 163 nonelderly adult Medicaid managed care (MMC) enrollees and 54 465 commercially insured enrollees in 5 states adopting access standards, and 37 290 MMC enrollees in 5 matched states that previously adopted access standards. Reported access to specialty care in the previous 6 months. Seven thousand six hundred ninety-eight (69%) Medicaid enrollees and 28 423 (75%) commercial enrollees reported that it was always or usually easy to get an appointment with a specialist before the policy implementation (or at baseline) compared with 11 889 (67%) of Medicaid enrollees in states that had previously implemented access standards. Overall, there was no significant improvement in timely access to specialty services for MMC enrollees in the period following implementation of standard(s) (adjusted difference-in-differences, -1.2 percentage points; 95% CI, -2.7 to 0.1), nor was there any impact of access standards on insurance-based disparities in access (0.6 percentage points; 95% CI, -4.3 to 5.4). There was heterogeneity across states, with 1 state that implemented both time and distance standards demonstrating significant improvements in access and reductions in disparities. Specialty access standards did not lead to widespread improvements in access to specialist physicians. Meaningful improvements in access to specialty care for Medicaid recipients may require additional interventions.

AGING WITH A PHYSICAL DISABILITY IN MEDICAID MANAGED CARE

This study examines health services appraisal (HSA) and unmet health-care needs for adults (age 50 and over) with physical disabilities in Medicaid managed care (MMC) versus Medicaid fee for service (FFS). Surveys from 309 individuals in MMC and 349 in FFS 2 years after MMC implementation included demographics, MMC processes, HSA, and unmet health-care needs. Regression analyses with HSA and unmet health-care needs as outcomes included demographics and group status (MMC or FFS) for the entire sample, and demographics and MMC processes (continuity of care, experience with care coordinators and primary care physicians) as independent variables for only MMC enrollees. Group status was not associated with HSA or unmet needs. Among MMC enrollees, better health and more positive MMC processes related to higher HSA and lower unmet needs. It is important to consider the perspectives of people aging with disabilities in MMC to better serve their needs.

Care coordination experiences of people with disabilities enrolled in medicaid managed care

Purpose: To understand the impact of experience and contacts with care coordinators on Medicaid Managed Care (MMC) enrollees with disabilities.Method: Primary data was collected from a random sample of 6000 out of the 100,000 people with disabilities enrolled in one state’s mandatory MMC program. Surveys were conducted through the mail, telephone, and Internet; 1041 surveys were completed. The sample used for analysis included 442 MMC enrollees who received care coordination. Regression analyses were conducted with the outcomes of number of unmet health care needs and enrollee appraisal of the health services they received. Race, age, gender, and disability variables controlled for demographic differences, and the independent variables included enrollee experience with a care coordinator (coordinator knowledge of enrollee medical history and whether the coordinator took into account enrollee wishes and input) and frequency of contact with a care coordinator.Results: Positive enrollee experiences with care coordinators significantly related to more positive enrollee health service appraisals and fewer unmet health care needs; frequency of contact did not have any significant impacts. People with mental health disabilities and intellectual/developmental disabilities had significantly lower health service appraisals. People with mental health disabilities had significantly more unmet needs.Conclusions: Quality of care coordination, but not frequency of contact alone, is associated with better health outcomes for MMC enrollees.Implications for rehabilitationCare coordination is a core component of managed care and facilitates effective healthcare management for people with complex chronic conditions and disabilities.Better experiences with care coordinators is related to fewer unmet healthcare needs and more positive health care service appraisals for Medicaid managed care enrollees.The continuous development of person-centered care coordination strategies and training programs emphasizing quality relationships between coordinators and consumers should be prioritized.

Health services appraisal and the transition to Medicaid Managed Care from fee for service

BackgroundMany states are transitioning fee-for-service (FFS) Medicaid into Medicaid Managed Care (MMC) for people with disabilities. ObjectiveThis study examined managed care's impact on health services appraisal (HSA) and unmet medical needs of individuals with disabilities receiving Medicaid. Key questions included 1) Do participant demographics and enrollment in MMC impact unmet medical needs and HSA? 2) Within MMC, do demographics and continuity of care relate to unmet medical needs? 3) Within MMC, do demographics, unmet medical needs and continuity of care relate to HSA? MethodsWe collected cross-sectional survey data (n = 1615) from people with disabilities in MMC operated by for-profit insurance companies (n = 849) and a similar group remaining in FFS (n = 766) in one state. Regression analyses were conducted across these groups and within MMC only. ResultsAcross Medicaid groups, MMC enrollment was not related to either HSA or unmet needs; health status, having a mental health disability and unmet transportation needs related to HSA and health status, unmet transportation needs and having a mental health or physical disability related to higher unmet medical needs. Within MMC, in addition to better health and fewer unmet medical needs, less continuity of care significantly decreased HSA. Higher unmet transportation needs, poorer health status, having a physical or mental health disability, and less continuity of care significantly decreased unmet medical needs. ConclusionsThis research points to the importance of meeting unmet needs of individuals in MMC and the need for increased continuity of care as people transition from FFS.

Validation of the Minimum Data Set in Identifying Hospitalization Events and Payment Source

To evaluate the accuracy of the Minimum Data Set (MDS) in identifying hospitalization events and payment source among nursing home residents. The 2003 MDS, Medicare Provider Analysis and Review File (MedPAR), Medicare denominator file, Medicaid Analytical Extract (MAX) long-term care file, and MAX personal summary file for 4 states (California, Ohio, New York, and Texas) were obtained and merged. All Medicare/Medicaid-certified nursing ho-mes in these 4 states during 2003. All nursing home residents who were eligible for Medicare. Medicare or Medicaid managed care enrollees were excluded. Using the identification by linking the MDS and claims data as the "gold standard," we calculated false negative and false positive error rates of the MDS in identifying hospitalization events and payment source. As for the accuracy of the MDS in identifying hospitalization events, the false negative error rates ranged from 6.8% to 19.5% and the false positive error rates were between 12.0% and 15.7%, depending on the state. With regard to the identification of Medicare payment source, the MDS had a low false negative rate (varying from 0.4% to 1.1%), and a relatively high false positive rate (ranging from 6.1% to 14.9%). The MDS alone did not seem to be a sufficient source for identification of Medicaid payment source (false negative rate ranging from 11.0% to 55.3%). The accuracy of the MDS in identifying hospitalizations and payment sources varies across the study states, and should be evaluated carefully with regard to the intended uses of the data.

Participant Satisfaction Methods and Outcomes in Medicaid Managed Care

Participant satisfaction is an important outcome in evaluating the effectiveness of healthcare programs and benefits. With vulnerable populations, such as Medicaid beneficiaries, determining participant satisfaction poses unique challenges. The purpose of this article is to discuss participant satisfaction methods and outcomes from a multi-year experience of surveying Medicaid Managed Care (MMC) participants in Nebraska (2000-2005). Using a variety of survey methods, the foci were to measure satisfaction with MMC enrollment, understanding of MMC guidelines, and satisfaction with education services provided. Results illustrate response rate patterns and outcome trends that contribute to quality improvement knowledge useful for others surveying Medicaid populations.

Effect of Prior Authorization of Second-Generation Antipsychotic Agents on Pharmacy Utilization and Reimbursements

Effect of Prior Authorization of Second-Generation Antipsychotic Agents on Pharmacy Utilization and Reimbursements

State Medicaid Managed Care Enrollment: Understanding the Political Calculus That Drives Medicaid Managed Care Reforms

The objective of this article is to understand the political motivations underlying Medicaid managed care reforms by examining the determinants of enrollment of beneficiaries in managed care plans in the fifty states. To highlight the role of the model variables, including measures of the political environment, public interest, and special interests, a distinction is made between capitated and fee-for-service managed care enrollment. The results show that cost containment within the context of the Medicaid program is perceived as strongly favored by voters. Accordingly, the relative cost and tax price of providing Medicaid services are important factors in states' decision to enroll Medicaid beneficiaries in managed care plans, particularly capitated ones. The results also indicate a surprisingly significant influence by labor unions that generally oppose managed care enrollment for fears of lost jobs. The recipient population and provider groups also play an important role in shaping the Medicaid managed care landscape. The influence of variables measuring states' ability and willingness to pay and median voter preferences suggest that, within the context of Medicaid managed care enrollment, the public's interests are being served; however, the results also point toward inequities within the program and implications concerning financing arrangements between states and the federal government.

Impact of the HealthChoice Program on Cesarean Section and Vaginal Birth after C-Section Deliveries: A Retrospective Analysis

To assess the impact of the HealthChoice program in Maryland on cesarean section and vaginal birth after C-section deliveries. Pre-post design using a comparison group with Maryland State Inpatient Databases, part of the Healthcare Cost and Utilization Project, developed by the Agency for Healthcare Research and Quality. Although the combined 1995 and 2000 database contained over 1.2 million inpatient discharge records, the analysis included all hospital discharge abstracts for women in labor. To identify the delivery, Diagnoses-Related Groups (DRGs) 370-375 were used from the discharge data. Together, there were 128,743 births identified in both years. Pregnant women enrolled in Medicaid managed care were compared pre-implementation and post implementation with pregnant women delivering babies under private insurance. The analysis computed difference-in-differences estimates using a logistic regression model that controlled for maternal characteristics, payment source, labor and delivery complications, and hospital characteristics. The outcome variables included Primary Cesarean, Repeat Cesarean, and Vaginal Birth after C-section. These results suggest that Medicaid managed care enrollees were less likely to undergo cesarean section deliveries relative to privately insured beneficiaries. Medicaid MCOs may have done a better job of limiting the growth in overused procedures than did MCOs and providers for privately insured women. This study has shown that there has been an overall increase in the use of primary and repeat cesarean sections in Maryland hospitals. However, HealthChoice limited this increase for Medicaid enrollees relative to privately insured women. On the other hand, vaginal births after C-section have declined in Maryland.

Medicaid markets and pediatric patient safety in hospitals.

To examine the association of Medicaid market characteristics to potentially preventable adverse medical events for hospitalized children, controlling for patient- and hospital-level factors. Two carefully selected Agency for Healthcare Research and Quality (AHRQ) pediatric patient safety indicators (decubitus ulcers and laceration) are analyzed using the new pediatric-specific, risk-adjusting, patient safety algorithm from the AHRQ. All pediatric hospital discharges for patients age 0-17 in Florida, New York, and Wisconsin, and at risk of any of these two patient safety events, are examined for the years 1999-2001 (N=859,922). Logistic regression on the relevant pool of discharges estimates the probability an individual patient experiences one of the two PSI events. Pediatric discharges from the 1999 to 2001 State Inpatient Databases (SIDs) from the AHRQ Healthcare Cost and Utilization Project, merged with hospital-level data from the American Hospital Association's Annual Survey, Medicaid data obtained from the Centers for Medicare and Medicaid Services and state Medicaid offices, and private and Medicaid managed care enrollment data obtained from InterStudy, are used in the estimations. At the market level, patients in markets in which Medicaid payers face relatively little competition are more likely to experience a patient safety event (odds ratio [OR]=1.602), while patients in markets in which hospitals face relatively little competition are less likely to experience an adverse event (OR=0.686). At the patient-discharge and hospital levels, Medicaid characteristics are not significantly associated with the incidence of a pediatric patient safety event. Our analysis offers additional insights to previous work and suggests a new factor--the Medicaid-payer market--as relevant to the issue of pediatric patient safety.

A Comparison of Self-Reported Use of Behavioral Health Services With Medicaid Agency Records in Minnesota

A Comparison of Self-Reported Use of Behavioral Health Services With Medicaid Agency Records in Minnesota

A Comparison of Self-Reported Use of Behavioral Health Services With Medicaid Agency Records in Minnesota

This study examined how well recipients of psychiatric or substance abuse services self-report their care. Self-reported use of behavioral health services, as reported by 1,012 respondents to a survey mailed to Minnesota Medicaid managed care enrollees receiving services with a behavioral health diagnosis other than severe mental illness in 2000, was compared with Medicaid agency records. Overall, 15 percent of respondents said they had not received services, although administrative data indicated otherwise. In bivariate analyses, failure to report treatment was associated with gender, age, education, and diagnosis but not with race or ethnicity or with residence. The effects of gender and diagnosis were insignificant after analyses controlled for age and education. Self-reports of behavioral health service use are a relatively accurate method of obtaining information on use. The finding that underreporting of receipt of behavioral health services was not random suggests that reporting errors could introduce bias when comparing groups that differ on age or education.

Effects of Medicaid managed care policies on mental health service use among a national probability sample of children in the child welfare system

Children in the child welfare system are dependent upon Medicaid to finance services for their considerable mental health needs. This study examines the effects of Medicaid policies on mental health service use among a national probability sample of children in the child welfare system. Data for this study came from the National Survey of Child and Adolescent Well-Being, the Caring for Children in Child Welfare study, and the Area Resource File. Weighted multivariate logistic regression analyses were conducted to estimate effects of policy variables on children's use of mental health services, controlling for child-level covariates and county-level health resources. Children in counties with behavioral carve-outs under Medicaid managed care had lower odds of inpatient mental health service use. Medicaid managed care enrollment and variations in type of provider reimbursement did not affect use of mental health services. Older age, greater need for mental health services, and higher levels of caregiver education were associated with increased odds of service use. Restrictions on use of inpatient mental healthcare caused by behavioral carve-outs may disproportionately affect children in the child welfare system who have high rates of such use. Careful adoption of carve-outs is necessary to assure appropriate care for these children.

Impact of a Decline in Colorado Medicaid Managed Care Enrollment on Access and Quality of Preventive Primary Care Services

Beginning in 1997 the Colorado Medicaid program de-emphasized managed care and shifted children from enrollment in a health maintenance organization (HMO), which required an enrollee to have an assigned primary care physician, to either the unassigned fee-for-service (UFFS) program in which the enrollee was not required to have a primary care physician (PCP) or to the primary care physician program (PCPP) in which the enrollee was required to select a participating PCP if one was available. The proportion of Medicaid enrollee-months in HMOs dropped from 75.4% in 1997 to 29% in 2003, whereas the proportion of enrollee-months in UFFS programs during this time period increased from 18.6% to 45.6%, and the proportion in the PCPP increased from 5.5% to 25.3%. This shift of children from HMO managed care to the UFFS program provided a natural experiment to assess the impact of not having an assigned PCP on pediatric primary care services. We sought to assess whether an elective shift of children from Medicaid HMO managed care plans with an assigned PCP to the UFFS program without an assigned PCP restricted access to a primary care medical home, recommended health supervision visits, and age-appropriate immunizations. Published Colorado Health Plan Employer Data and Information Set (HEDIS) data for 1999-2003 were reviewed to determine if Colorado children enrolled in Medicaid managed care programs with an assigned PCP (HMO and PCPP) compared with the UFFS program were more likely to have any type of visit with a PCP, to have recommended health supervision visits, and to be fully immunized. In the analysis, "HMO total" refers to the average of all children participating in HMO plans. Kaiser Permanente was considered a benchmark because it had the highest immunization rates of all HMOs. "Total Colorado" refers to the average of all children enrolled in Medicaid including the managed care and UFFS options. For 2-year-olds, the 4:3:2:1:1 combination immunization included 4 diphtheria-tetanus-acellular pertussis vaccines, 3 oral poliovirus vaccines or inactivated polio vaccines, 2 hepatitis B vaccines, 1 Haemophilus influenzae type b vaccine, and 1 measles-mumps-rubella vaccine. In 1999 the percentages of children 12 to 24 months of age having any type of visit with a PCP were >80% for the PCPP, Kaiser Permanente, and UFFS programs. However, although the proportion with any visit remained >85% in 2001 for children enrolled in the PCPP and Kaiser Permanente program, the percentage dropped 13.9% to 66.2% for children in the UFFS program. In 2001 the percentage of children with any type of PCP visit enrolled in the UFFS program (66.2%) was significantly lower than the total Colorado (73.6%) as well as the PCPP (85.7%) and Kaiser Permanente program (97.7%). Children 12 to 24 months of age enrolled in the PCPP in 2001 were 1.3 times more likely to have any type of visit with a PCP compared with those enrolled in the UFFS program. Children in the PCPP in 2001, 2002, and 2003 were 1.4, 1.9, and 2.6 times more likely, respectively, to have all 6 of the recommended health supervision visits compared with children enrolled in the UFFS program. Children 3 to 6 years old in the PCPP in 2001, 2002, and 2003 were 1.3, 1.5, and 1.4 times more likely, respectively, to have an annual health supervision visit compared with children enrolled in the UFFS program. In 1999, 2001, 2002, and 2003 2-year-old children enrolled in the PCPP were 2.0, 1.4, 1.5, and 1.8 times more likely, respectively, to be up-to-date with 4:3:2:1:1 vaccines compared with children enrolled in the UFFS program. In 1999, 2001, 2002, and 2003 adolescents enrolled in the PCPP were 1.8, 1.6, 1.3, and 1.6 times more likely, respectively, to be up-to-date with 2 measles-mumps-rubella vaccines compared with children enrolled in the UFFS program. This study documents the diminishing ability of the Colorado Medicaid program to provide children access to the benefits of a medical home, including visits with PCPs, recommended health supervision visits, and immunizations as care was shifted to the UFFS program from HMO managed care. The high up-to-date immunization rates achieved by Kaiser Permanente suggest that differences in immunization rates reflect the effectiveness of the care processes rather than the characteristics of the Medicaid population.

Identifying Areas for Improvement: Results of a Medicaid Managed Care Diabetes Survey

This study explores factors that contribute to dissatisfaction for Medicaid managed care enrollees with diabetes. Using results from a mail survey of 2,104 Medicaid managed care enrollees with diabetes, multivariate logistic regression models were fit for 3 outcomes: dissatisfaction with diabetes information from doctor or nurse, dissatisfaction with diabetes care received and dissatisfaction with health plan. Across the 3 models, enrollees who reported they were in poor health, who failed to engage in self-management activities, who reported little or inadequate patient education and/or who had difficulty accessing diabetes care were more likely to report dissatisfaction. The results of this study will be used to propose interventions that Medicaid managed care plans can initiate to improve satisfaction of enrollees with diabetes.

Medicaid Managed Care and Health Care for Children

Many states expanded their Medicaid managed care programs during the 1990s, causing concern about impacts on health care for affected populations. We investigate the relationship between Medicaid managed care enrollment and health care for children. DATA SOURCES AND MEASURES: Repeated cross-sections of Medicaid-covered children under 18 years of age from the 1996/1997 and 1998/1999 Community Tracking Study Household Surveys (n=2,602) matched to state-year CMS Medicaid managed care enrollment data. For each individual, we constructed measures of health care utilization (provider and emergency department visits, hospitalizations, surgeries); health care access (usual source of care, unmet medical needs, put-off needed care); and satisfaction (satisfaction overall, with doctor choice, and with last visit). Regression analysis of the relationship between within-state changes in Medicaid managed care enrollment rates and changes in mean utilization, access, and satisfaction measures for children covered by Medicaid, controlling for a range of potentially confounding factors. Increases in Medicaid health maintenance organization (HMO) enrollment are associated with less emergency room use, more outpatient visits, fewer hospitalizations, higher rates of reporting having put off care, and lower satisfaction with the most recent visit. Medicaid primary care case management (PCCM) plans are associated with increases in outpatient visits, but also with higher rates of reporting unmet medical needs, putting off care, and having no usual source of care. Both Medicaid HMO and PCCM plans can have important impacts on health care utilization, access, and satisfaction. Some impacts may be positive (e.g., less ED use and more outpatient provider use), although concern about increasing challenges in access to care and satisfaction is also warranted.

Asthma in Medicaid Managed Care Enrollees Residing in New York City: Results from a Post-World Trade Center Disaster Survey

The collapse of the World Trade Center on September 11, 2001, released a substantial amount of respiratory irritants into the air. To assess the asthma status of Medicaid managed care enrollees who may have been exposed, the New York State Department of Health, Office of Managed Care, conducted a mail survey among enrollees residing in New York City. All enrollees, aged 5-56 with persistent asthma before September 11, 2001, were surveyed during summer 2002. Administrative health service utilization data from the Medicaid Encounter Data System were used to validate and supplement survey responses. A total of 3,664 enrollees responded. Multivariate logistic regression models were developed to examine factors associated with self-reported worsened asthma post September 11, 2001, and with emergency department/inpatient hospitalizations related to asthma from September 11, 2001, through December 31, 2001. Forty-five percent of survey respondents reported worsened asthma post 9/11. Respondents who reported worsened asthma were significantly more likely to have utilized health services for asthma than those who reported stable or improved asthma. Residence in both lower Manhattan (adjusted OR = 2.28) and Western Brooklyn (adjusted OR = 2.40) were associated with self-reported worsened asthma. However, only residents of Western Brooklyn had an elevated odds ratio for emergency department/inpatient hospitalizations with diagnoses of asthma post 9/11 (adjusted OR = 1.52). Worsened asthma was reported by a significant proportion of this low-income, largely minority population and was associated with the location of residence. Results from this study provide guidance to health care organizations in the development of plans to ensure the health of people with asthma during disaster situations.

Influence of Medicaid managed care enrollment on emergency department utilization by children.

To explore the association between Medicaid managed care plan enrollment and emergency department (ED) utilization. Retrospective cohort analysis using administrative claims data. A total of 518 982 nondisabled children 1 to 18 years of age who were Medicaid beneficiaries in calendar year 2000. Annual visit rates per 1000 member-months and incidence rate ratios for complex and noncomplex ED visits. Medicaid beneficiaries were classified on the basis of months enrolled in managed care. Administrative claims for ED visits were classified as complex or noncomplex on the basis of procedure and diagnostic codes. Multivariate logistic regression models of the incidence rate ratios were used to compare children with varying degrees of enrollment in Medicaid man-aged care with a reference group consisting of those exclusively enrolled in Medicaid managed care. Overall, 22% of children receiving Medicaid made 1 or more ED visits in 2000; 77% of ED visits were for noncomplex services. Children who spent less than half of their enrolled months in managed care used complex ED services 37% more frequently (P<.001) and noncomplex services 11% more frequently (P<.001) than those exclusively enrolled in Medicaid managed care. Children with all of their Medicaid enrollment in managed care have the lowest ED utilization rates for complex and noncomplex services. These results suggest that reducing delays in managed care plan enrollment may be an effective strategy to reduce ED utilization for this population.