Graduation Year


Document Type




Degree Name

Master of Arts (M.A.)

Degree Granting Department

Communication Sciences and Disorders

Major Professor

Ruth Huntley Bahr, Ph.D.

Committee Member

Maria Brea-Spahn, Ph.D.

Committee Member

Michelle Hite, M.S.


Phonology, Orthography, Morphology, Dyslexia, Dysgraphia, OWL-LD, Spelling


Students diagnosed with specific learning disabilities struggle with spelling accuracy, but they do so for different reasons. For instance, students with dysgraphia, dyslexia, and oral-written language learning disability (OWL-LD) have distinct areas of weakness in cognitive processing and unique difficulties with the linguistic features necessary for accurate spelling (Silliman & Berninger, 2011). This project considered the spelling errors made by such students to determine if their unique learning profiles lead to distinct misspelling patterns.

Academic summaries handwritten by 33 students diagnosed with dysgraphia (n=13), dyslexia (n=15), and OWL-LD (n=5) were analyzed for type/complexity and number of spelling errors. Additionally, the differences in error frequency and complexity were analyzed based on whether academic material had been listened to or read. Misspellings were extracted from the students' essays and evaluated using an unconstrained linguistic scoring system (POMAS). Then, the complexity/severity of the misspelling was computed using a complexity metric (POMplexity).

Statistical results revealed that children within the diagnostic categories of dysgraphia, dyslexia, and OWL-LD appear to produce errors that are similar in complexity and frequency. Hence, students with specific learning disabilities do not appear to make patterns and numbers of errors specific to their diagnosis. Additionally, statistical results indicated that all students produced similar numbers of errors in both the reading and listening conditions, indicating that the mode of presentation did not affect spelling accuracy.

When spelling errors were analyzed qualitatively, some differences across diagnostic categories and variability within groups was noted. Students with dysgraphia produced misspellings involving a phoneme addition or omission. Phonological and orthographic errors typical of younger children were characteristic of misspellings produced by students with dyslexia. Individuals with OWL-LD tended to omit essential vowels and were more likely to misspell the same word in multiple different ways.

Overall, these results indicate that the subcategories of dysgraphia, dyslexia, and OWL-LD represent of gradients of impairment within the overarching category of specific learning disabilities. However, even within those subcategories, there is a wide degree of variability. Diagnostic categories, then, may suggest areas of linguistic weakness, but subcategories alone cannot be used for determining the nature of spelling intervention.