Iowa Tests
March 06, 2009
The Iowa Tests are categorized in two areas. The Iowa Tests of Basic Skills (ITBS) which is administered to students in grades 2-8 and the Iowa Tests of Educational Development which is administered to students in grades 9-11.
Three of the fundamental purposes for testing are (1) to describe each student's developmental level within a test area, (2) to identify a student's areas of relative strength and weakness in subject areas, and (3) to monitor year-to-year growth in the basic skills. To accomplish any one of these purposes, it is important to select the type of score from among those reported that will permit the proper interpretation. Scores such as percentile ranks, grade equivalents, and standard scores differ from one another in the purposes they can serve, the precision with which they describe achievement, and the kind of information they provide. A closer look at these types of scores will help differentiate the functions they can serve and the meanings they can convey. Additional detail can be found in the Interpretive Guide for Teachers and Counselors.
In Iowa, school districts can obtain scores that are reported using national norms or Iowa norms. On some reports, both kinds of scores are reported. The difference is simply in the group with which comparisons are made to obtain score meaning. A student's Iowa percentile rank (IPR) compares the student's score with those of others in his/her grade in Iowa. The student's national percentile rank (NPR) compares that same score with those of others in his/her grade in the nation.
