Stability of WISC-R intelligence scores: Implications for 3-year reevaluations of learning disabled students

Student records of 170 learning disabled students from two area agencies were examined to determine the stability of WISC-R test scores administered as part of the 3-year reevaluation of students required by Public Law 94–142. The WISC-R had been readministered to 150 of these students. Stability coefficients were .72, .70, and .74 for the Verbal, Performance, and Full Scale IQ scores. Changes in Full Scale scores were 4 points or less for 52% of the sample. Changes greater than 15 points were noted for 4% of the sample. Results suggest that WISC-R scores are reasonably stable over a 3-year interval, and routine readministration of the WISC-R should not be required or encouraged.