The Need for Control/Comparison Studies in Establishing Diagnostic Indicators

Abstract

Typical assessment profiles for students with different diagnostic labels are often determined without the use of comparison groups. This practice often leads to misconceptions that certain characteristics are unique to individuals with that label. This, in turn, could lead to inappropriate diagnostic decisions and possible mislabeling. To illustrate this point, we compared the psychometric characteristics of a sample of individuals with Prader-Willi syndrome with those of a control group of individuals without Prader-Willi syndrome who had similar attributes. These characteristics have been considered to be unique to Prader-Willi syndrome. Results indicated that the cognitive, behavioral, and educational characteristics that have been reported for individuals with Prader-Willi syndrome were documented but were not unique to the syndrome. The importance of using comparison groups when establishing diagnostic criteria is discussed, using these results as an example.

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References

Caldwell, M.L. , & Taylor, R. (1983). A clinical note on food preference of individuals with Prader-Willi syndrome: The need for empirical research. Journal of Mental Deficiency Research, 27, 45–49.

Cohen, J. (1957). A factor-analytically based rationale for the Wechsler Adult Intelligence Scale. Journal of Consulting Psychology, 21, 451–457.

Holm, V. (1981). The diagnosis of Prader-Willi syndrome. In V. Holm , S. Sulzbacher , & P. Pipes (Eds.), Prader-Willi syndrome. Baltimore: University Park Press.

Kaufman, A. (1981). The WISC--R and learning disabilities assessment: State of the art. Journal of Learning Disabilities, 14, 520–526.

Ledbetter, D. , Riccardi, V. , Airhart, S. , Strobel, R. , Keenan, B. , & Crawford, J. (1981). Deletions of chromosome 15 as a cause of the Prader-Willi syndrome. The New England Journal of Medicine, 304, 325–329.

Prader-Willi Syndrome Association. (1984). The gathered view. Edina, MN: Author.

Taylor, R. (1988). Cognitive and behavioral characteristics. In M.L. Caldwell & R. Taylor (Eds.), Prader-Willi syndrome: Selected research and management issues (pp. 29–42). New York: Springer-Verlag.

Taylor, R. , & Caldwell, M.L. (1988). Parent concerns. In M.L. Caldwell & R. Taylor (Eds.), Prader-Willi syndrome: Selected research and management issues (pp. 83–92). New York: Springer-Verlag.

Taylor, R. , Ziegler, E. , & Partenio, I. (1984). Investigation of WISC--R verbal performance discrepancies as a function of ethnic status. Psychology in the Schools, 21, 436–444.

10.

Warren, J. , & Hunt, E. (1981). Cognitive processing in children with Prader-Willi syndrome. In V. Holm , S. Sulzbacher , & P. Pipes (Eds.), Prader-Willi syndrome (pp. 161–178). Baltimore: University Park Press.

11.

Zellweger, H. , & Schneider, H. (1968). Syndrome of hypotonia-hypogonadism-hypomentia-obesity (HHHO) or Prader-Willi syndrome. American Journal of Diseases of Children, 115, 588–598.