1. A computer-assisted method of test assembly for assembling a test comprised of a plurality of slots to be filled by test items comprising: executing a test administration script to associate each of the plurality of slots of the test with an item collection from which an item to fill the slot is to be selected; obtaining an interim test score based on a portion of the test previously assembled; and applying an optimization process to control statistical properties of the test based on the interim score and properties of the items within the item collection associated with each of the plurality of slots.