In order to prevent “gaming” or overcoding of risk scores within the program, CMS has limited ACOs to only receive credit for increases to risk score of 3% between their benchmark period and performance period. However, the risk scores within the ACO’s region—to which the ACO is directly compared for the purposes of benchmark development—are not capped or limited in any way. This inconsistency in risk score capping is described within the following and is currently disadvantaging all ACOs in regions with relatively higher risk score growth.

CMS "Capping" ACO Potential: The Need for Capped Regional Risk Scores