A LONGITUDINAL STUDY OF WISC-R SCORES OF STUDENTS EXPERIENCING LEARNING DIFFICULTIES by

The stability of intelligence test scores over time was examined for the Wecnsler Intelligence Scale for Children- Devised(WIS:-R). Subjects included 64 children aged 6-16, vho had been administered the WISC-R during prior evaluations. These:udents hadbeen referred because of academic difficulties. One-third of the sample had taken the test twice, one-third three times, and ono-thirdfour times. Verbal intelligence quotient (IQ), performance IQ, andfull scale IQ scores were el/Etna-tile. Correlations and t values values were computed between the first and second, second and third, and third and fourth W1SC-R administrations. Results indicated test stability coefficients ranged from.71 to.93 for verbal IQ, from.76to.88 for performance IQ, and from.69 to.93 for full scale IQ. Forthe 22 students who had four te..cing experiences, mean scores werebelow average each time. Scores generally decreased slightly in subsequent test administrations. An analysis using Pearson correlations showed the following statistically significant correlations between test trials: verbal,.71 to.93; performance,.69 to.88; and full IQ,.66 to.93. It was concluded that the WISC-Ris a reliable test, over tine, when used with school-age children experiencing learning difficulties. (GDC