The purpose of this investigation was to examine the item characteristics of the General Educational Development Tests (GED) for specific subgroups of students. The method employed was the approach suggested by Linn and Harnisch in which the three-parameter logistic model is used for detecting interactions between item content and group membership. Data used in this investigation came from four separate forms of the GED writing test administered to national representative samples during the spring term of the 1979-1980 testing cycle. Results of the study are summarized for the five content categories (spelling, capitalization/punctuation, usage, sentence completion, and logic and organization) on the writing test for female students for each of the four forms. The discussion of the results suggest that the interactions between item content and group membership may be conceptualized as indications of multidimensionality. (PN)