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The Case Against Using Profile Analysis With Gifted/Learning Disabled Students
Historically, there has been a strong and enduring belief in the existence of multiple and
distinct intellectual abilities (Kehle, Clark, & Jenson, 1993). From Thurstone to Gardner, the
theory of multiple intelligences has continued to influence intellectual assessment. In addition, the
Wechsler IQ scales contain 10 to13 distinct subtests, undoubtedly influencing school psychologists�
belief in the interpretability of distinct subtest profiles (Kehle et al.). The subtests on the
Wechsler scales appear to measure divergent content, and most educators intuitively believe that
students display unique patterns of strengths, weaknesses, and learning styles. Therefore, educators
and psychologists often feel tempted to use the subtest scores to reveal a student�s unique
pattern of cognitive strengths and weaknesses. Profile analysis refers to the practice of interpreting
differences among subtests as evidence of differential and distinct pattern of cognitive functioning
in a student. Many practitioners continue to interpret the profile of subtest scores, even in the face
of overwhelming empirical research that cautions against such practice (Kavale & Forness, 1984;
Kramer, Henning-Stout, Ulman, & Schellenberg, 1987; McDermott, Glutting, Jones, Watkins, &
Kush, 1989; Sattler, 1992; Truscott, Narrett, & Smith, 1993).
The arguments presented by Bray, Kehle, and Hintze (1998) against the use of profile analysis
in psychoeducational diagnoses are also applied here as arguments against the diagnosis as
gifted/learning disabled using similar procedures. They also suggest that profile analysis should
not be employed because �individual subtests are not as reliable as deviation IQs and/or factor
scores as indicated by their corresponding reliability and stability coefficients, standard error of
measurement (SEm), and confidence intervals. . .� (p. 211).
Further, as stated by Bray et al. (1998), even with the use of the most rigorous .01 level of
significance to lower the probability of a Type I error, any statistically significant differences
among subtests may be quite common occurrences in children�s patterns of scores, and consequently
of little practical significance. For example, Bray et al. noted that �a difference of 11
points between the verbal and performance scales is significant at the .05 level for all ages, but it
occurs in 40.5 percent of the standardization sample on the WISC III (Wechsler, 1991)� (p. 212).
Also, Jensen (1992) argued that profile analysis uses ipsative scores and therefore removes
generalized variance; consequently g is substantially diminished. According to Watkins and Kush
(1994), the use of ipsative score analysis is simply an inappropriate method to interpret test results.
Although the full-scale IQ score is remarkably stable, there is variability in the profile as a result
of the lower reliabilities of the individual subtests. Consequently, a particular profile does not
represent a particular disorder such as a learning disability (Truscott et al., 1993;Watkins & Kush,
1994).
Using profile analysis to identify students as both gifted and learning disabled can be especially
problematic. There is evidence to suggest that the scaled score range among subtests increases
as the full-scale IQ score increases (Patchett & Stansfield, 1992) and that subtest scatter increases
with as the value of the highest subtest score rises (Schinka, Vanderploeg, & Curtiss, 1997). If
these findings are true, then intellectually gifted children would display more atypical and scattered
profiles than other students. Therefore, profile analysis would capitalize on chance variability,
and would be especially inappropriate for students of superior ability. Waldron and Saphire
(1990) found that both gifted students and gifted/learning disabled students showed strengths in
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the similarities subtest and deficits in digit span. They also noted that neither examining verbal/
performance discrepancies nor rank ordering the WISC-R subtests provided an effective method
of identifying or documenting the existence of a learning disability. Therefore, there appears to be
even greater evidence to refute the use of profile analysis with gifted or gifted/LD students than
there is for the general school population.