Figure 2.

Study periods in relationship to the HRRP announcement and implementation of penalties for COPD. The study years were divided into three nonoverlapping periods (preannouncement, announcement, and implementation), based on the HRRP announcement date (April 2010) and the implementation of penalties specific for COPD (October 2014). We excluded admissions in the year of 2012 owing to limitations in linking beneficiary identification. COPD = chronic obstructive pulmonary disease; HRRP = Hospital Readmissions Reduction Program.