Multi-Site Implementation: Medicaid Section 1931(b) in California

This paper uses the implementation of the new Medicaid 1931(b) program in California and its 58 counties to consider multi-site implementation. Given California's county-operated welfare system, the California Department of Health Services (CDHS) made policy that each of the state's 58 counties was to implement. Combining unusually rich administrative data, official documents, and qualitative field work, the authors find that actual implementation occurred as much as several years later than was required by state-level policy, with considerable heterogeneity across the counties, and that the heterogeneity was to a great extent due to the details of computer systems. The paper concludes with a discussion of the implications of these results for implementation and the study of implementation.