The Dyslexia Subtyping Test (DST): Design and construct-related validation.

• Main Author: Roberts, Rhiannon.
• Other Authors: Bos, Candace
• Language: en
• Published: The University of Arizona. 1995
• Online Access: http://hdl.handle.net/10150/187301

Estimates indicate that students with learning disabilities (LD) represent 3-5% of the school population and that about 80% of these individuals evidence a reading disability or dyslexia. Because appropriate instruction depends upon correct classification, experts suggest that, if students are to be helped, research must shift to documenting specific subtypes within the classification of dyslexia. Historically, one of the most accepted theoretical models suggests the existence of three types of dyslexia. Under a variety of terms, the major subtypes, phonologic, orthographic, and mixed dyslexia, have been identified by practitioners throughout the years. Although many measures of phonologic processing are available currently, no widely-accepted measure of orthographic processing exists. The intent of the current study, therefore, was to create an instrument (Dyslexia Subtyping Test (DST)) that subtypes dyslexia into phonologic, orthographic, and phono/ortho or mixed dyslexia. Based upon suggestions found in recent research, the DST addresses dyslexia subtypes across two domains; receptive or decoding tasks and expressive or encoding tasks. Future revisions and directions for dyslexia subtyping are discussed.