“…Whenever possible, the levels ofprocessing effect was broken down within each study into separate subconditions, such as number of repetitions (Challis & Brodbeck, 1992;Schacter & McGlynn, 1989), type of stimuli (Schacter, Cooper, & Delaney, 1990;Srinivas & Roediger, 1990), combinations of input and test stimulus (Graf & Ryan, 1990), and retention interval (Chiarello & Hoyer, 1988;Squire, Shimamura, & Graf, 1987). When both recall and recognition tests were given (Besson, Fischler, Boaz, & Raney, 1992;Hashtroudi, Ferguson, Rappold, & Chrosniak, 1988;Light & Singh, 1987), recall was used to represent the explicit test.…”