Evaluation of working memory training

Consider the evaluation of the computerized Cogmed working memory training with N=44 first-graders screened for low working memory (i.e., under the 15th percentile in the Automated Working Memory Assessment). The primary outcome was the score on the Wide Range Achievement Test (WRAT, standard mean score = 100, SD = 15), with higher scores indicating higher performance. The significance level is set to α=5% one-tailed.

Table 1. Observed WRAT scores at Pretest, Posttest, and D=Pre-Post
WRATPretestPosttestD¯
Average79.982.3-2.5
SD2.02.81.9