For better or worse, independent medical practices and solo community hospitals are disappearing as they are acquired by hospital-based health systems. In this issue of JAMA, Beaulieu et al provide a detailed review of the current (2018) prevalence and performance of the 580 health systems they identified in the US. They found that 84% of general acute care hospital beds and 40% of physicians were part of health systems. These findings are compatible with those of Furukawa et al, who used a somewhat different method to identify 637 systems in 2018 that included 91% of US hospital beds and 51% of physicians, marking increases of 3 and 11 percentage points, respectively, since 2016.
