At the end of 2016, there were 626 health systems in the United States, according to new research from the Agency for Healthcare Research and Quality (AHRQ). A health system is defined as including at least one hospital and at least one physician group that provides comprehensive care (including primary and specialty care) who are connected with each other and with the hospital through common ownership or joint management. About 69.7% of hospitals, and 88.2% of all hospital beds, are in a health system. About 92% of hospital discharges are from health system hospitals. About 44.6% of . . .