Related Experiment Videos
WISC-R subtest reliability over time: implications for practice and research
S D Truscott1, C M Narrett, S E Smith
1Graduate School, School Psychology Program, Alfred University, NY 14802-1232.
Psychological Reports
|February 1, 1994
Summary
The Wechsler Intelligence Scale for Children-Revised (WISC-R) shows moderate to good reliability for IQ scores over time in learning disabled students. However, subtest scores can be inconsistent, impacting interpretation.
Area of Science:
- Educational Psychology
- Neuropsychology
- Psychometrics
Background:
- The Wechsler Intelligence Scale for Children-Revised (WISC-R) is a widely used tool for assessing cognitive abilities in children.
- Understanding the stability of WISC-R scores is crucial for accurate diagnosis and educational planning for learning disabled students.
Purpose of the Study:
- To investigate the test-retest reliability of WISC-R IQ scores and subtest scaled scores.
- To examine score stability over 3- and 6-year intervals in a sample of learning disabled students.
Main Methods:
- Statistical analysis of WISC-R scores from 107 students with at least two evaluations.
- Individual score variability analysis was conducted.
- A subsample of 41 students with three evaluations over 6 years was also analyzed.
Main Results:
- Three-year test-retest reliabilities for Verbal IQ, Performance IQ, and Full Scale IQ were .69, .72, and .77, respectively.
- Subtest reliabilities varied widely (.33 to .71), with a median of .49, and nine subtests below .62.
- Individual analyses revealed significant score fluctuations, with some students showing IQ changes up to 33 points.
Conclusions:
- While overall WISC-R IQ scores demonstrate reasonable stability, subtest scores exhibit considerable inconsistency.
- This variability poses challenges for the interpretation of individual subtest performance.
- Findings suggest caution in relying on specific subtest scores for diagnostic or intervention planning and raise questions for WISC-III research.