Naming speed deficits in reading disability: multiple measures of a singular process.

Speed of word identification is important in the theories of reading proposed by La Berge and Samuels (1974) and Perfetti (1985), and is substantially correlated with reading skill. However, there is controversy about whether disabled readers have a speed deficit that is restricted to the identification of printed words, or if instead, they have a more general speed deficit in retrieving names of even single digits. To investigate this issue, poor and average readers (N = 43) in grade 2 were assessed on several indices of speed of digit and letter naming, using both continuous-list and discrete-trial methodologies. MANCOVA indicated clear effects of reader group on discrete-trial latencies, as well as an interaction between reader group and the speed with which to-be-named items were presented. A series of hierarchical regression analyses explored the amount of shared variance between various measures of digit naming speed and five indices of reading skill. Latency for word identification shares considerable variance with latency for digit naming, and, in general, accounts for the shared variance of naming speed and several other measures of reading skill. Naming speed contributed variance in reading skill. Naming speed contributed variance in reading skill independently of measures of phonological awareness.