Quality Improvement at the Health System Level: Measurement, Risk Stratification, Disparity Populations, and Governance.

Value-based health systems encompass a range of care-delivery models from small independent practices to large integrated delivery systems and academic medical centers. In addition, public and private payers, federal and state agencies, professional societies, and not-for-profit organizations collect and analyze data for quality and value improvement in health care-delivery outcomes. In this article, we review the multidimensional aspects of data collection, aggregation, analysis, and use for and by value-based health systems.