Much of the effort involved in a major restructuring of the Graduate Record Examinations (GRE) Aptitude Test was intended to result in the creation of an analytical module to supplement the verbal and quantitative sections of the test, thus providing broadened measurement. Factor extension analysis was used in the present study to investigate further the characteristics of seven experimental analytical item types that had been administered in the experimental section of two operational forms of the Aptitude Test. The extension analysis included: (1) examining the loadings of analytical items on the factors extracted from operational forms, (2) computing the contribution made by operational factors to explaining both the intercorrelations among experimental items and the variance of each experimental test, and (3) analyzing the relationships among analytical items that were not explained by operational form factors. The seven analytical item types were shown to be differentially related to the dimensions underlying the current Aptitude Test, in terms of both their independence of verbal and quantitative factors and their relationship to specific abilities. Furthermore, all but one of the seven experimental analytical tests appeared to have at least one interpretable dimension that was distinct from any found in the operational form of the Aptitude Test. (Author)