The delta-plot method (Angoff, 1972) is a graphical technique used in the context of test equating for identifying common items with aberrant changes in their item difficulties across administrations or alternate forms. This brief research report explores the effects on equated aggregate scores when delta-plot outliers are either retained in or discarded from the common item pool, using real data from large-scale assessment programs from three states. (Contains 2 tables and 1 figure.)