This paper presents a combination Bayesian/Item Response Theory procedure for pooling performance on a particular objective with information about an examinee’s overall test performance in order to produce more stable objective scores. The procedure, including the calculation of a posterior distribution, is described. A split-half cross validation study finds that a credibility interval based on the posterior distribution is sufficiently accurate to be useful for scoring reports for teachers. [Author abstract; reproduced with permission of CTB/McGraw-Hill LLC. Copyright 1987 by CTB McGraw-Hill LLC. All rights reserved]