Applying health service utilization models to the Texas Healthcare Transformation and Quality Improvement Program: Advancing theory-based evaluation

Centers for Medicare and Medicaid Services (CMS) granted Texas a Section 1115(a) waiver in March 2011 to expand the existing Medicaid managed care programs statewide to maintain/improve health outcomes while containing cost growth. CMS mandates an evaluation of this system transformation involving $29 billion and impacting at least four-million Texas Medicaid clients. Given the conceptual and technical design issues, Texas developed an evaluation plan capable of discovering/examining unintended program effects and designed to maximize the evaluation generalizability. The large-scale program evaluation conceptualized/operationalized program impacts and health outcomes using Chen's (2005) conceptual framework for program theory and Anderson's (1995) model of health service utilization. Theory-based evaluation permitted investigators to detect missing components (e.g., client health behaviors and provider-client interactions) while developing an evaluation plan to capture multi-level effects of managed care expansion including components of the environment (e.g., local health care systems and managed care organizations), population characteristics, health service utilization, and health outcomes. Identified components determined data to be collected and statistical methodology to monitor and track process (short-term) outcomes and health outcome indicators (intermediate outcomes) over the demonstration period. Texas is only the second state to implement such a large-scale managed care expansion through a Medicaid waiver. By providing comprehensive information on the program’s structure, implementation procedures, and potential causal mechanisms, Texas and CMS will better understand its underlying mechanisms and determine whether the program achieved its goals. Findings are intended to provide a theory-based evaluation that may be relevant to other states implementing similar managed care programs.