Validities of Abreviated Scales of the Wechsler Intelligence Scale for Children

CHAPTER I. INTRODUCTION Recent years have witnessed the rapid and widespread growth of psychological testing, resulting in a demand for adequate psychological services in a wide variety of situations . Education, industry, the courts, social agencies, institutions, and the armed services have put a severe strain on clinics where time has come to be at a premium in evaluation and diagnosis. Under these conditions, there exists a pressing need for tests which require a minimum of administration time, yet are valid and reliable enough to contribute accurately to an adequate evaluation of the subject. LIMITATIONS AND TYPES OF BRIEF INTELLIGENCE TESTS In the construction and use of such brief tests, certain limitations must immediately be faced. Reliability necessarily declines as the sample of behavior, on the basis of which a diagnosis must be made, diminishes. Furthermore, the lack of opportunity to observe a subject\u27s response to a sufficiently wide variety of tasks limits the clinician’s ability to make the qualitative judgments valuable in determining the level of the subject’s over-all adjustment. There is danger that inexperienced personnel, placing too great a degree of confidence in the results of limited samplings of behavior, may make decisions detrimental, not only to the patients directly involved, but also, indirectly, to the field of psychometrics itself. Arguments like these have generated much dispute over the advisability of using brief psychological tests. Yet in the face of overloaded and understaffed clinics, where it is manifestly impossible to devote sufficient time to each case for extensive testing in every area, some compromise is necessary, and justifiable, as long as the admitted limitations of such a compromise are recognized. Consequently, the usefulness of brief tests as screening devices for determining the areas in which more extensive testing should, perhaps, be done, is seldom questioned. Cognizant of these facts, numerous investigators have conducted studies in an effort to fill the need for brief yet valid and;reliable tests. Several investigators have constructed new tests designed to be used as screening devices and gross indicators of intellectual level. One such brief intelligence test is the Full-Range Picture Vocabulary Test of Ammons and Ammons (1) This test, which covers the developmental period from the two year through the adult level, is recommended for those with speech handicaps because the subject need only point in order to Indicate his response, dorsini (5) developed a vocabulary test requiring five minutes to administer and score. This test, The Immediate Test, is an age scale consisting of 66 words and covering the mental age range from 10 to 20 years. The Kent EGY series (15, 16), which test a wide range of abilities, represent another well-known attempt at the rapid screening of abilities with a view to the estimation of the need for more extensive testing