Trends in hospital network participation and system affiliation, 2007-2012.

: Key Findings. (1) Hospital network participation from 2007 to 2012 increased in larger hospitals (more than 150 beds), non-government not-for-profit hospitals, and metropolitan hospitals. Network participation changed inconsistently in other types of hospitals. (2) Hospital system affiliation has generally increased in hospitals of all sizes, non-government not-for-profit hospitals, hospitals in all census regions, CAHs, and both metropolitan and nonmetropolitan hospitals. There are notably higher percentages of system affiliation among midsized and large hospitals, investor-owned hospitals, and metropolitan hospitals compared to their counterparts.