Certain clinical tests of widely reputed importance to reading disability have been applied, together with semi-automated visual sample-matching tasks, to a randomly selected school population of good and poor readers. Those performance deficits found with significant frequency among the poor readers of normal intelligence include laterality awareness of body parts (although not laterality preference), and visual sample-matching with three-letter words where the match involved only the order of letters within the word. Coincidence of these two findings suggests that further study might elucidate some more general deficit of laterality awareness in significant portions of the total population of normally intelligent poor readers.
Rosenberger PB. Visual Matching and Clinical Findings Among Good and Poor Readers. Am J Dis Child. 1970;119(2):103-110. doi:10.1001/archpedi.1970.02100050105002