Several indices of factorial consistency were applied to a biographical inventory administered to a longitudinal sample of 2070 students in the 7th, 9th, and 11th grades. Results were compared with those of a prior cross-sectional study at the same grade levels. Comparisons of dimensional change over the three grades, for the cross-sectional and longitudinal sample, showed general similarities in the number of major factors extracted, their designations and the variance accounted for. However, there were marked differences between the samples in their factor intercorrelations and the developmental changes shown in factor "presence." A transition effect associated with the factor pattern of the 9th grade was found only in the longitudinal sample. The importance of identifying the extent of factorial invariance for measures used in studying patterns of behavioral development is discussed. (Author)