The Survey of Young Adult Literacy conducted in 1985 by the National Assessment of Educational Progress included sixty-three items that elicited skills in acquiring and using information from written documents. These items were analyzed in two distinct ways: (1) with an item response theory (IRT) model, which characterized items' difficulties and respondents' proficiencies as revealed simply by tendencies toward correct response, and (2) a qualitative cognitive model, which characterized items in terms of the processing tasks they required. This paper demonstrates how a generalization of Fischer and Scheiblechner's Linear Logistic Test Model can be used to integrate information from the cognitive analysis into the IRT analysis. (45pp.)