ERIC Number: EJ1057238
Record Type: Journal
Publication Date: 2015-May
Abstractor: As Provided
Reference Count: N/A
Beyond the Floor Effect on the Wechsler Intelligence Scale for Children-4th Ed. (WISC-IV): Calculating IQ and Indexes of Subjects Presenting a Floored Pattern of Results
Orsini, A.; Pezzuti, L.; Hulbert, S.
Journal of Intellectual Disability Research, v59 n5 p468-473 May 2015
Background: It is now widely known that children with severe intellectual disability show a 'floor effect' on the Wechsler scales. This effect emerges because the practice of transforming raw scores into scaled scores eliminates any variability present in participants with low intellectual ability and because intelligence quotient (IQ) scores are limited insofar as they do not measure scores lower than 40. Method: Following Hessl et al.'s results, the present authors propose a method for the computation of the Wechsler Intelligence Scale for Children-4th Ed. (WISC-IV)'s IQ and Indexes in intellectually disabled participants affected by a floored pattern of results. The Italian standardization sample (n?=?2200) for the WISC-IV was used. The method presented in this study highlights the limits of the "floor effect" of the WISC-IV in children with serious intellectual disability who present a profile with weighted scores of 1 in all the subtests despite some variability in the raw scores. Results: Such method eliminates the floor effect of the scale and therefore makes it possible to analyse the strengths and weaknesses of the WISC-IV's Indexes in these participants. Conclusions: The Authors reflect on clinical utility of this method and on the meaning of raw score of 0 on subtest.
Descriptors: Severe Mental Retardation, Raw Scores, Scores, Foreign Countries, Evaluation Methods, Test Bias
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Authoring Institution: N/A
Identifiers - Location: Italy
Identifiers - Assessments and Surveys: Wechsler Intelligence Scale for Children