Assessment of retrieval strategy in incidental, intentional, and inclusion tests with word-fragment cues

The purpose of this study was to assess retrieval strategy in incidental, intentional, and inclusion tests with word-fragment cues following a levels-of-processing manipulation at study. The results of Exp. 1 showed small levels-of-processing effects in incidental tests, and most subjects reported involuntary rather than voluntary retrieval of study-list words. In an intentional test, although levels of processing had a much greater effect, quite a few subjects also reported involuntary rather than voluntary retrieval of study-list words, and these subjects showed a smaller effect of levels of processing than subjects reporting voluntary retrieval. These results suggest that subjects given instructions for both voluntary and involuntary retrieval of study-list words in an inclusion test might not in fact attempt voluntary retrieval at all, but simply adopt an involuntary retrieval strategy. The results of Exp. 2 provided evidence to support this suggestion. The general implication is that where test contamination refers to subjects' failure to use retrieval strategies in accordance with test instructions, inclusion tests can be contaminated, as well as incidental or intentional tests, and that it is always necessary to obtain converging evidence about the actual strategies subjects use.