Although studies exist measuring the effectiveness of writing interventions for students with autism spectrum disorder (ASD), research assessing the writing skills for this group is sparse. The present study identified differences in the written expression of individuals with ASD compared to typically developing (TD) peers, using variables selected from 13 different studies. Using Pearson Product Moment-correlation the relationship between the quality of research studies and the magnitude of the effect sizes was examined. Findings indicate significant differences in the following components of written expression; length, legibility, handwriting size, speed, spelling, and overall structure, highlighting the need for future research to determine if the characteristics of written expression in individuals with ASD are similar to other struggling writers.