Table 1:

Characteristics of patient populations across 11 sites observed from 2011 to 2016

Number of sites	11
Academic Medical Centersa	9
Community Hospitals	2
Age in years
25th percentile (Median [range])	39 [36.5, 40.8]
50th percentile (Median [range])	54.3 [51.5, 55.8]
75th percentile (Median [range])	65 [64.1, 66.8]
Female sex % (median [range])	56.8 [51.7, 60.9]
Race
White % (Median [range])	64.1 [27.8, 90.0]
African American % (Median [range])	26.8 [6.2, 60.6]
Asian % (Median [range])	1.2 [0.1,1.9]
American Indian or  Alaska Native % (Median [range])	0.2 [0.1, 0.4]
Pacific Islander % (Median [range])	0.1 [0.0, 0.2]
Other/Unknown % (Median [range])	5.9 [1.8, 14.4]
Unique Patients with Encounters per Year
Median [range]	248,533 [44,476, 3,200,408]
Sum of Medians Across Sites	7,204,434
Unique Patients with Target Prescriptionsb per Year
Median [range]	55,781 [5,036, 282,397]
Sum of Medians Across Sites	844,307

Summary statistics were derived from site-level, across-year medians. For example, the median [range] of unique patients with encounters was derived by calculating site-specific median number of encounters per year across observed years and then by calculating the median [range] of the site-specific median values. For the 25th percentile of age summary, at each site, we calculated the 25th percentile of age each year and then used the median of those values. The median [range] reported in the table is the across-site median [range] of the site-specific median values for the 25th percentiles.

^aOne participating site (Site 11) is considered an Academic Medical Center and a Community Hospital.

^bTarget prescriptions defined as CPIC Level A drugs or alternative medications within the class.