Date of Award


Document Type

Open Access Dissertation


Educational Studies


Educational Psychology / Research

First Advisor

Kellah Edens


Developmentally, it is expected that the processes of working memory and processing speed will improve throughout childhood as a child's brain develops. However, students with learning, attention, and other childhood disorders often display difficulties in these areas. This study investigated the use of repeated measures to ascertain variability over time of two important cognitive processes: Working Memory and Processing Speed in a clinically referred population as measured by the WISC-IV to determine if a significant discrepancy exists between administrations. The study also investigated whether differences in Working Memory and Processing Speed from administration to administration would be greater in children with ADHD (Attention Deficit Hyperactivity Disorder) vs. students with SLD (Specific Learning Disability). WISC-IV scores in Working Memory and Processing Speed from two administrations were examined from confidential archival records for 75 children ages 6-14. A two-way repeated analysis of variance (ANOVA) was conducted for hypothesis one with time as the

within factor. A mixed ANOVA was conducted for the second hypothesis with group as the between factor and time as the within factor. Time was defined as the interval from one administration to the next. Second administrations were an average of two and a half years later. For hypothesis one, Processing Speed was statistically significant for time as a main effect although results were not statistically significant for Working Memory. For hypothesis two, Working Memory was statistically significant for time and group. The ADHD students performed significantly higher than SLD on Working Memory. Only time as a main effect was statistically significant for Processing Speed. Additional analyses examined medication status as well as comorbidity and gender as confounds. Those experiencing a medication change from one administration to the next as well as boys were significantly lower on Processing Speed.

Findings suggest students can perform quite variably across time even within the elementary school years. This research highlights the importance of repeat cognitive assessment in evaluating developmental disorders across time. Changes in Working Memory or Processing Speed determine types of interventions as well as accommodations that may be needed. This has ramifications for educational decisions regarding these students.