Long-Term Stability of Intelligence and Achievement Scores in Specific-Learning-Disabilities Samples

Abstract

To compile data useful for informed reevaluation decisions that concern specific-learning-disabled (SLD) children, the stability of the Wechsler Intelligence Scale for Children-Revised (WISC-R) and Wide Range Achievement Test (WRAT) scores was assessed over a period of approximately 3 years in two samples of SLD children. Both samples began in a part-time learning-disabilities program (SLD-P). At the second WISC-R testing, 68 students remained in the part-time program, and 31 students had been placed in a full-time SLD program (SLD-PF). The WISC-R IQ reliabilities were high with the exception of Verbal IQ(VIQ) in the SLD-PF group. WRAT scores were less reliable. For both groups, VIQs decreased and Performance IQs (PIQs) increased over time. In the SLD-P group WRAT-Math scores decreased over time, and in the SLD-PF group WRAT-Spelling scores decreased over time. Regression analyses that used time in program as a covariate revealed unimpressive effects of program on WISC-R and WRAT scores. Cautions about program placement and the experimental design are discussed.

The Stability of WISC-III Scores: For Whom are Triennial Re-Evaluations Necessary?

“…Learning disabled population . Anderson, Cronin and Kazmierski (1989) These results are similar to that of Kaye and Baron (1987) who examined the WISC-R test-retest stability of ninety-nine learning disabled children over a three year period .…”

“…Previous research investigating the stability of the WISC-R with a homogeneous group of children in special education suggest that significant intra-individual variability exist across the three IQ measures (Elliott & Boeve, 1987;Truscott, Narrett & Smith, 1994;Vance, Blixt, Ellis & Debell, 1981;Webster , 1988 interval These result s are inconsistent with previous research investigating the stability of the WISC and WISC-R Significant mean increases in VIQ , and significant mean decreases in PIQ were reported for a group oflearning disabled children administered the WISC twice over a fifteen month interval ( Coleman , 1963 ). Similar trends were reported investigating the stability of the WISC-Rover a three-year interval (Anderson , Cronin , & Kazmiers~ 1988;Elliott & Boeve , 1987;Kaye & Baron , 1987;Haddad , Juliano & Vaughan, 1984). It was believed that increased Performance IQ scores in a learning disabled population was a result of practice effects (Covin , 1977) .…”

Post WISC-R and TOVA Improvement with QEEG Guided Neurofeedback Training in Mentally Retarded: A Clinical Case Series of Behavioral Problems

“…In 1991 Streissguth, Randels, and Smith 32 reported that IQ scores of patients with fetal alcohol syndrome or possible fetal alcohol effects remained stable over the average test / retest interval of 8 years. Both Haddad, Juliano, and Vaughan (1994) 33 and Kaye and Baron (1987) 34 reported that with learning disabled children WISC-R Verbal IQ scores tended to decrease while Performance IQ scores increased over a 3-year period.…”

Case Study: Improvements in IQ Score and Maintenance of Gains Following EEG Biofeedback with Mildly Developmentally Delayed Twins

“…Cheng, Liu and Gong (1993) reported that across a 1.5 to 2 year interval, both learning disabled and normal children displayed stable Verbal, Performance, and Full Scale IQ scores on a Chinese version of the WISC-R. Streissguth, Randels and Smith (1991) reported that IQ scores of patients with fetal alcohol syndrome or possible fetal alcohol effects remained stable over the average test/retest interval of eight years. Both Haddad, Juliano and Vaughan (1994) and Kaye and Baron (1987) reported that with learning disabled children WISC Verbal IQ scores tended to decrease while Performance IQ scores increased over a threeyear period. Finally, Spitz (1986) reviewed the history of attempts to raise IQ in developmentally delayed and/or culturally disadvantaged children.…”