The purpose of this study was to compare three variables in terms of how well they predict orthographic functioning. To this end, the authors examined the relative contributions of rapid automatic naming, exposure to print, and visual processing to a composite measure of orthographic functioning in a heterogeneous group of 8- to 12-year-old children. Hierarchical regression analyses revealed that rapid naming, exposure to print, and visual processing were each predictive of orthographic functioning when controlling for the other variables as well as vocabulary knowledge and phonological awareness. Thus, it appears that both linguistic and visual abilities are related to orthographic functioning.
Mesman, Glenn R and Kibby, Michelle Y. "An examination of multiple predictors of orthographic functioning.." Journal of Learning Disabilities 44, No. 1 (Jan 2011): 50-62. doi:10.1177/0022219410371675.