Reading and Writing: An Interdisciplinary Journal 9: 55–63, 1997.
1997 Kluwer Academic Publishers. Printed in the Netherlands.
Can self-report data on deﬁcits in reading and spelling predict
spelling disability as deﬁned by psychometric tests?
ORNE, WOLFGANG DEIMEL and
Department of Child and Adolescent Psychiatry and Psychotherapy, Philipps-University,
Abstract. Questionnaire data concerning spelling and reading self-assessment, habits, and
school history were obtained for 79 adults (54 women and 25 men). The items were used
to predict affectedness as deﬁned on the basis of psychometric tests. For this purpose, two
different discriminant analytical approaches (linear discriminant analysis and hierarchical
classiﬁcation with CART) were compared using a cross-validation design. 86.8–92.6% of the
learning sample and 87.5–88% of the cross-validation sample were classiﬁed correctly. The
CART model was preferred due to a balanced relation of sensitivity and speciﬁcity. Our results
support the conclusion that self-report data are appropriate to substitute psychometric tests if
these cannot be administered.
Key words: Spelling disorder, Reading ability, Self-assessment
Reading and spelling disorder (also called dyslexia) is one of the most
frequently diagnosed disorders in childhood. The prevalence rate varies
between 5 and 10 percent depending on the chosen diagnostic criteria and
sample ascertainment strategies (Shaywitz, Shaywitz, Fletcher & Escobar
1990). Longitudinal studies showed a high continuity of the disorder into
adulthood, especially for spelling disorder (Michelsson, Byring & Bj
1985; Strehlow, Kluge, M
oller & Haffner 1992).
As recommendedbythe different classiﬁcation systems (DSM IV and ICD-
10), the diagnosis is based on standardised tests of reading and spelling. For
adults, there is no consensus with regard to the procedure that should be used
for diagnosis. Self-report data regarding school history (Gillis & DeFries
1989) and self-assessment of actual reading and spelling ability (Decker,
Vogler & DeFries 1989) as well as psychometric tests are used for diagnosis
(Pennington, Gilger, Pauls, Smith, Smith & DeFries 1991). As an alternative
to individual testing, administering a questionnaire is less time consuming
and does not requireindividualcontacttothe examined individual. Therefore,
this diagnostic procedure is often preferred for adult phenotype deﬁnition in
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