The denominators for the mortality rate calculations were fixed in both groups as the number of treatment and matched comparison group members in the final matched sample for the first six intervals (since all sample members had at least 36 months of followup, with mortality data available through 2011), and restricting the samples in later intervals to those whose period of sample entry would allow us to observe their mortality in a particular interval.17
Compared to both NH entrants and HCBS waiver enrollees in the first matched comparison group, in all ten intervals throughout the 60-month followup period, PACE enrollees had a lower mortality rate than enrollees in the matched comparison group, with the difference being statistically significant in all intervals (Table 13). A year after enrollment, about 9 percent of PACE enrollees had died compared to nearly 22 percent for the matched comparison enrollees. Three years after enrollment, the rates were around 29 percent and 44 percent respectively among the PACE and the matched comparison groups, and by the end of the followup period (month 60), nearly 43 percent of PACE enrollees were deceased compared to nearly 51 percent for their matched counterparts who were NH entrants or HCBS waiver enrollees. The difference in mortality ranged from eight to nearly 17 percentage points during each six-month interval after the first post-enrollment year.
Compared to matched HCBS waiver enrollees alone, PACE entrants still had significantly lower mortality in most intervals through month 60, except in the last two intervals, where mortality rates in the two groups were similar (Table 14). Also, the difference in mortality was much smaller--around 5-6 percentage points--in most intervals after the first post-enrollment year and through month 48 after enrollment.