An index measuring the degree to which a binary response pattern conforms to some baseline pattern was defined and named the Pattern Conformity Index (PCI). One way of conceptualizing what the PCI measures is the extent to which each individual's particular response pattern contributes to, or detracts from, the overall consistency found in the group's mode of responding. One use of the PCI consists of spotting anomalous response patterns that result from a student's problems. From this it is a short step to utilizing the PCI for identifying a subgroup of students for whom the given set of items approximately constitutes a unidimensionally scalable set. The duality between students and items then permits selection of a subset of items for further improving the unidimensionality. A measure of how constant an individual's response pattern remains for parallel subsets of items ocurring earlier and later in a test was developed and called the Individualized Consistency Index (ICI). (Author/BW)