"Intuitively, many healthcare professionals have believed for years that individual hospital alignment is a key to health system success, but alignment has been difficult to quantify. Put simply, we wanted to determine how well health systems are achieving the goal of delivering a consistent patient experience in each of their facilities, and start benchmarking that performance each year," said Jean Chenoweth, Senior Program Director, 100 Top Hospitals Programs, IBM Watson Health. "Based on our data, it is clear that better hospital alignment does indeed play a role in overall health system performance, and it is something we will be investigating further."

IBM researchers evaluated a total of 338 health systems and 2,422 member hospitals. Performance was measured through nine benchmarks that included risk-adjusted inpatient mortality index, risk-adjusted complications index, mean healthcare-associated infection index, mean 30-day risk-adjusted mortality rate, mean 30-day risk-adjusted readmission rate, severity-adjusted length of stay, mean emergency department throughput, Medicare spend per beneficiary index and Hospital Consumer Assessment of Healthcare Providers and Systems score.