Dr. McWilliams’s research focuses on health care spending, quality, access, and disparities in aging populations with chronic conditions. His current research focuses on accountable care organizations (ACOs), measurement of low-value care, organizational determinants of technology diffusion, risk adjustment of prospective payments and quality measures, and the effects of provider consolidation on health care utilization and prices. Some of his most recent publications have appeared in JAMA, JAMA Internal Medicine, Health Services Research, and Health Affairs.