Koroukian SM, Bush D, Rimm AA; Association for Health Services Research. Meeting.
Abstr Book Assoc Health Serv Res Meet. 1999; 16: 264-5.
Department of Epidemiology and Biostatistics, School of Medicine, Case Western University, Hilliard, OH 43026-0210, USA.
RESEARCH OBJECTIVE: Medicaid managed care programs have been available to Aid for Families with Dependent Children (AFDC) eligibles residing in Ohio's major metropolitan counties for more than a decade, and enrollment in Health Maintenance Organizations (HMOs) has been growing over the last several years. The percentage of HMO births to AFDC mothers residing in these counties increased from 12% in 1992 to 40% in 1996. During the study period, HMO emrollment for AFDC eligibles was mandatory in one county (Dayton area) and voluntary in all other major metropolitan counties. In 1997 HMO enrollment became mandatory for AFDC eligibles in most major metropolitan counties. While initial reports have documented significant differences in risk adjusted rates of Cesarean section (C-section) in the AFDC population between women receiving their care through traditional fee-for-service (FFS) systems and those enrolled in HMOs, it is not known whether such differences persist over time. This paper examines temporal changes in adjusted C-section rates between FFS and HMO among AFDC women. We also examine changes in neonatal outcomes between 1992 and 1996. STUDY DESIGN: This is a population-based study using linked live birth certificate and Medicaid data. The two files were linked using identifiers to the mothers and the infants, and a match rate of 83% or greater was achieved for each of the study years, 1992, 1993, 1995, and 1996. The study includes only liveborn, singleton infants born to AFDC eligible mothers residing in metropolitan counties (n=63,869). Women and infants were grouped in the FFS population if they had a delivery/birth claim paid through the FFS system, and in the HMO population if the infant was enrolled in an HMO as of the first month of life, and in the absence of a FFS birth claim. Analyses were conducted on two separate groups of women to study primary C-section rates and repeat C-section rates. In each of the FFS and HMO populations, these groups included respectively women with no history of previous C-section, and those with at least one previous C-section. Temporal changes were analyzed by medical indication (maternal medical risk factors and complications of labor and delivery), as well as in relation to changes in the use of obstetrical procedures (Electronic Fetal Monitoring (EFM) and operative vaginal deliveries). Logistic regression analysis was conducted separately for each of the outcomes of primary C-section and repeat C-sections to determine factors associated with these rates. In addition, temporal changes in neonatal outcomes, as measured through Apgar scores, were analyzed in each of the populations. RESULTS: Between 1992 and 1996, the rates of primary C-section increased from 8.5% to 10.0% (by 18%) in the HMO population, and from 11.1% to 12.0% (by 8.1%) in the FFS population. However, repeat C-section rates decreased from 66.9% to 61.1% (by 9%) in the HMO population, and from 73.8% to 65.1% (by 12%) in the FFS population. During this time, significant increases occurred in the use of EFM (from 74% to 90%, or by 22%), and in the use of vacuum extractors (from 5% to 6%, or by 20%). The results of the logistic regression analyses yielded adjusted odds ratios (AORs) for HMO enrollment of 0.48 and 0.53 (significant at p<0.001), respectively for primary C-section rates and repeat C-section rates. However, the interaction term of the HMO variable by the study year proved to be statistically significant for repeat C0sections (AORs 1.17, p<0.001), indicating that the difference between HMO and FFS rates decreased between 1992 and 1996. No temporal changes between the HMO and FFS populations were found when Apgar scores were analyzed. CONCLUSIONS: The difference in the risk adjusted rates of C-section between FFS and HMO enrollees in the AFDC population decreased between 1992 and 1996. Apgar scores were similar for HMO and FFS during the study period. POLICY IMPLICATIONS: The significant expansion of the Medicaid HMO market resulting from the mandatory aspect of HMO enrollment, and the maturity of the plans involved represent important changes in the financing and delivery of care for the Medicaid program. It has been generally recognized that some C-sections are unnecessary. The fact that C-sections are lower in prepaid plans suggests that the method of payment may impact unnecessary C-sections.
Publication Types:
Keywords:
- Aid to Families with Dependent Children
- Cesarean Section
- Child
- Fee-for-Service Plans
- Female
- Health Care Sector
- Health Maintenance Organizations
- Humans
- Infant
- Live Birth
- Managed Care Programs
- Medicaid
- Ohio
- Population Groups
- Pregnancy
- Pregnancy Outcome
- Regression Analysis
- economics
- surgery
- hsrmtgs
Other ID:
UI: 102193910
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