FIGURE 1.

SPC u-chart of DDI alerts per 100 medication orders per week. Dates of AAG alert refinements are indicated by arrows, and individual refinements are detailed in Table 1. Upper control limit and lower control limit were determined by using weekly data before AAG refinement efforts (from February 1, 2015, to December 20, 2015). 5SL, 5 σ limit; −5SL, negative 5 σ limit.