This study investigated the test-retest reliabilities of the WISC—R IQs and scaled scores on subtests over 3- and 6-yr. intervals for a learning disabled sample. Statistical procedures and individual analyses were conducted on a sample of 107 students who had at least two evaluations. For the total sample, 3-yr. test-retest reliabilities of the Verbal IQ, Performance IQ, and Full Scale IQ were .69, .72, and .77, respectively. Subtest reliabilities ranged from .33 to .71, with a median of .49, but nine subtests had reliabilities of .62 or lower. Individual analyses indicated considerable variability, with some students decreasing as much as 33 IQ points on retest. Similar results were noted for a subsample of 41 students who had three evaluations over a 6-yr. period. Problems with subtest interpretation due to the inconsistency of the WISC—R scores and extensions of this research to the WISC—III are discussed.
Get full access to this article
View all access options for this article.
References
1.
AndersonP.CroninM. E.KazmierskiS. (1989) WISC—R stability and revaluation of learning disabled students. Journal of Clinical Psychology, 45, 941–944.
2.
BaumanE. (1991) Stability of WISC—R scores in children with learning difficulties. Psychology in the Schools, 28, 95–100.
3.
CovinT. M. (1977) Stability of the WISC—R for 9-year-olds with learning difficulties. Psychological Reports, 40, 1297–1298.
4.
ElliottS. N.PierselW. C.WittJ. C.ArgulewiczE. N.GutkinT. B.GalvinG. A. (1985) Three year stability of WISC—R IQs for handicapped children from three racial/ethnic groups. Journal of Psychoeducational Assessment, 3, 233–244.
5.
GuilfordJ. P.FruchterB. (1978) Fundamental statistics in psychology and education. (6th ed.) New York: McGraw-Hill.
6.
HaynesJ. P.HowardR. C. (1986) Stability of WISC—R scores in a juvenile forensic sample. Journal of Clinical Psychology, 42, 534–537.
7.
JulianoJ. M.HaddadF. A.CarrollJ. L. (1988) Three-year stability of WISC—R factor scores for black, white, female and male children classified as learning disabled. Journal of School Psychology, 26, 317–325.
8.
KaufmanA. S. (1979) Intelligent testing with the WISC—R. New York: Wiley.
9.
LallyM. J.LloydR. D.KulbergJ. M. (1987) Is intelligence stable in learning disabled children?Journal of Psychoeducational Assessment, 4, 411–416.
10.
MartinR. P. (1983) Ethics column. The School Psychologist, Spring, 6, 8.
11.
NaglieriJ.PfeifferS. (1983) Reliability and stability of the WISC—R for children with below average IQs. Educational and Psychological Research, 3, 203–208.
12.
NunnallyJ. C. (1978) Psychometric theory. (2nd ed.) New York: McGraw-Hill.
13.
OakmanS.WilsonB. (1988) Stability of WISC—R intelligence scores: Implications for 3-year reevaluations of learning disabled students. Psychology in the Schools, 25, 118–120.
14.
ReschlyD. J.GenshaftJ.BinderM. S. (1987) The NASP Survey: Comparison of practitioners, NASP leadership, and university faculty on key issues. Washington, DC: National Association of School Psychologists.
15.
ReynoldsC. R.GutkinT. B. (1980) Stability of the WISC—R factor structure across sex at two age levels. Journal of Clinical Psychology, 36, 775–777.
16.
SalviaJ.YssfidykeJ. E. (1991) Assessment. (5th ed.) Boston, MA: Houghton Mifflin.
17.
SattlerJ. M. (1988) Assessment of children's abilities. (3rd ed.) San Diego, CA: Author.
18.
SmithM. D. (1978) Stability of WISC—R subtest profiles for learning disabled children. Psychology in the Schools, 15, 4–7.
19.
SpitzH. H. (1983) Intratest and intertest reliability and stability of the WISC, WISC—R, and WAIS Full Scale IQs in a mentally retarded population. Journal of Special Education, 17, 69–80.
20.
StavrouE. (1990) The long-term stability of WISC—R scores in mildly retarded and learning disabled children. Psychology in the Schools, 27, 101–110.
21.
TumaJ.AppelbaumA. S. (1980) Reliability and practice effects of WISC—R IQ estimates in a normal population. Educational and Psychological Measurement, 40, 671–678.
22.
University of the State of New York, State Education Department. (1987) Regulations of the Commissioner of Education. Subchapter P. Part 200. Albany, NY: SUNY.
23.
USDHEW. (1977) Education of handicapped children: Implementation of Part B of the Education of the Handicapped Act. Federal Register, 42(163), 42474–42518.
24.
VanceH. B.BlixtS.EllisR. (1981) Stability of the WISC—R for a sample of exceptional children. Journal of Clinical Psychology, 37, 397–399.
25.
VanceH. B.HankinsN.BrownW. (1987) A longitudinal study of the WISC—R over a six-year period. Psychology in the Schools, 24, 229–233.
26.
WebsterR. E. (1988) Statistical and individual temporal stability of the WISC—R for cognitively disabled adolescents. Psychology in the Schools, 25, 365–372.
27.
WechslerD. (1974) Manual for the Wechsler Intelligence Scale for Children—Revised. New York: Psychological Corp.
28.
WechslerD. (1991) Manual for the Wechsler Intelligence Scale for Children—III. New York: Psychological Corp.
29.
WhortonJ. E. (1985) Test-retest WISC—R scores for 310 educable mentally retarded and specific learning disabled students. Psychological Reports, 56, 857–858.
