Many studies have examined reading and reading development. The majority of these studies, however, focused on oral reading
rather than on the more dominant silent reading mode. Similarly, it is common practice to assess oral reading abilities rather
than silent reading abilities in schools and in diagnosis of reading impairments. More important, insights gained through
examinations of oral reading tend to be generalized to silent reading. In the current study, we examined whether such generalizations
are justified. We directly compared oral and silent reading fluency by examining whether these reading modes relate to the
same underlying skills. In total, 132 fourth graders read words, sentences, and text orally, and 123 classmates read the same
material silently. As underlying skills, we considered phonological awareness, rapid naming, and visual attention span. All
skills correlated significantly with both reading modes. Phonological awareness contributed equally to oral and silent reading.
Rapid naming, however, correlated more strongly with oral reading than with silent reading. Visual attention span correlated
equally strongly with both reading modes but showed a significant unique contribution only to silent reading. In short, we
showed that oral and silent reading indeed are fairly similar reading modes, based on the relations with reading-related cognitive
skills. However, we also found differences that warrant caution in generalizing findings across reading modes.