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Report · February 2020

Improving Health Care Data in California

Shannon McConville, Paulette Cha, Caroline Danielson, and Daniel Tan

Supported with funding from the California Health Care Foundation

California policymakers are taking steps to create a health care payment database (HPD) often referred to as an all-payer claims database-that would assemble comprehensive payment information on health care services provided to most state residents with public or private health insurance. Rising costs and a lack of transparency are key motivators of this effort, but an overarching goal is to make health care data available to a wide range of stakeholders-including insurers, employers, health care providers, consumers, state agencies, and researchers-in order to continuously monitor and evaluate health care use, expenditures, and outcomes.

A California HPD would cover a larger and more diverse population than databases in other states, and could be a critical resource for addressing some of the state’s most pressing challenges, including homelessness, untreated mental illness, and the well-being of children. Not only could an HPD offer a crucial source of information about current spending patterns, but it would also be an essential tool to monitor the effects of policy changes.

This report offers examples of research that could be developed and/or enhanced by an HPD. It also reports our findings from in-depth interviews and an online survey to highlight insights and potential contributions of the California research community. There are several key takeaways:

  • An HPD promises to provide better data to address questions related to health care cost drivers, including health provider consolidation and patient costs. Research using data from an HPD could also shed light on the continuity of health care coverage for California’s children and how coverage lapses may impact use of preventive services.
  • An HPD holds the potential to inform statewide policy by facilitating broader access to data required to evaluate local intervention and pilot programs. For example, it could enhance studies aimed at identifying successful housing interventions that lower costs and improve outcomes among low-income, chronically ill Californians or inform efforts to prevent child maltreatment.
  • California’s research community could serve as a valuable resource for developing, monitoring, and maintaining a successful HPD. California’s many higher education and research institutions could serve as partners in organizing and vetting the data. Nearly all of the researchers we interviewed indicated they would apply to use data from a California HPD and would be willing to pay for access.
  • Key features of an HPD that would ensure that it is a high-quality tool for policy researchers include the ability to follow individuals over time and across insurance plans, demographic information, and data on costs, rebates, and alternate payments. Researchers also prioritize linkages to other health data, such as vital statistics, hospital discharges, and disease registries. Lastly, linkages to social safety net and other administrative data could benefit research in arenas’such as employment and child welfare-that may be affected by health or health care.
  • In addition to the HPD, California policymakers are planning other large-scale databases to bring together state administrative data. Examples include a database to capture longitudinal education and employment information and a database to integrate information across multiple social safety net programs. The future may hold opportunities to link these data systems and further improve data for policy-relevant research.

As policymakers consider the future of health insurance and health care in California-including a single-payer system and other major insurance reforms-a reliable, timely, and comprehensive source of information on who pays how much for health care services holds the potential to drive evidence-based policymaking.


Health & Safety Net Population