CROSS-VALIDATION STUDY OF ITEM ORDERING OF PEABODY PICTURE VOCABULARY TEST

A subset of the items of both forms of the Peabody Picture Vocabulary Test (PPVT) was administered to a sample of 452 fourth‐, fifth‐ and sixth‐grade students. This sample of students was randomly divided into two equal subgroups. Item difficulty indices were calculated for each of the two subsamples for each of the two forms of the test. Data obtained from the first subsample were used to evaluate the published ordering of items of Forms A and B of the PPVT and to reorder the items according to the empirically derived item difficulties. The second subsample was used as a cross‐validation sample to evaluate the empirically derived reordering of items. The results of the cross‐validation of the reordering indicate a substantial and significant increase in the validity of the item orderings for this subset of items on both forms of the PPVT. Therefore, this new ordering may yield a more accurate estimate of the intelligence of average and above students in the fourth‐, fifth‐, and sixth‐grades than the present, published ordering of items. Copyright © 1969, Wiley Blackwell. All rights reserved