The school psychologist may be regarded as a professional agent who not only measures a student's ability and interprets his scores, but also communicates a child's achievements to his parents, to his teachers and to the school administrators. Recommendations concerning a child's classroom assignment, be it to a class for educable mentally retarded, emotionally disturbed or normals, certainly will affect his destiny. Many a psychologist, with good justification, places great stock in intelligence test results. One of the consistently stable predictors of scholastic achievement has been the intelligence test score. By far, the most frequently used type of intelligence test is the paper and pencil, objectively keyed measure. This type of test is seriously limited in its ability to measure that portion of the school population that demonstrates deficits in certain motor or complex functions, such as reading. Therefore, psychologists have administered the individual test of ability to assess the marginally able student. One of the two tests popularly used for such purposes is the Wechsler Intelligence Scale for Children (WISC), the subject of the present study.Recommendations that stem from individual tests of ability are largely prognostic in nature. Like other predictiqn situations, their utility depends on the validity and reliability of the ability and achievement tests. With respect to validity, Zach (1966) brings to our attention an alternative explanation of the high ability and achievement relationship, namely, children whose obtained ability scores are low are placed in classes for slow learners and foqa variety of reasons perform poorly in class. Hence, poor performance may be due to factors confounded with low ability classroom placement and fulfills the poor performance prophecy.The focus of the present study is on the second of the two points made earlier, namely, reliability. Watson (1967a, 196713) found that psychologists showed low interjudge agreement of the Draw-A-Person Test. He reported that diagnostic impressions based on DAP alone were neither valid nor consistent between raters. In addition, the accuracy of the judges' diagnoses was only slightly above chance and uncorrelated with hospital-record impressions. In an investigation of factors that affect agreement among clinicians, Huff (1966Huff ( , 1967 reported that interjudge agreement was affected by almost every variable manipulated. Of the several variables tested, ratings of intelligence based on WAIS scores provided the highest reliability.Satler and Winget (1970) studied the effect of WAIS scripts on the scoring of WAIS protocols. Accomplices memorized responses to Comprehension, Similarities, and Vocabulary items. They found that more credit for ambiguious responses was given to Ss believed to have high IQs than to those believed to have lower IQs, which suggests a constant error in the scoring of this test. Massey (1965) urged the adoption of a more uniform scoring system for the Wechsler scales. He found that the range of scores of c...
