The Cooperative Interest Index was chosen for the Educational Testing Service Comparative Prediction Study as the best predictor of college fields. Unlike some other inventories, the 200 items list activities which are familiar to high school students. Cooperative Interest Index scores indicate interest in the following fields: English, modern languages, mathematics, social studies, biology, physical science, music, fine arts, industrial arts, business, home economics, sports, manual (in general), and reading (in general). The validities for these scales were encouraging, particularly for differential prediction purposes. A revision was undertaken to make the Index more useful. Item studies were carried out, involving freshman course grades and major field satisfaction. Items were classified as: popular among students later enrolling in the field; effective for predicting grades; effective for providing satisfaction; or not effective in any of these categories. All these criteria were considered in evaluating item validity. Some items were revised and many were added, bring the item pool to 293 items. The test will continue to have about 200 items. Further plans include pretesting of the new items and revising the manual. The test will be presented first as experimental, and additional data will be collected.
