Language impairment at school entry and later reading disability: Connections at lexical versus supralexical levels of reading

This study employed the distinction between lexical and supralexical processes in reading in order to gain a more fine-grained picture of the relationships between early language impairment and later reading disabilities. We hypothesized that early semantic-syntactic deficits would be only weakly related, if at all, to the characteristically modular word recognition processes involved in reading isolated words and pseudowords. On the other hand, early language deficiencies were expected to be significantly associated with processes operating beyond the level of individual words when children are required to read and understand connected text. These predictions were tested using data from a longitudinal study of over 500 unselected children followed from kindergarten to the end of Grade 1. Both traditional categorical analyses of specific subgroups with early language impairment or later reading disability as well as dimensional (regression) analyses were carried out. As predicted, higher order language was found to be related to supralexical aspects of reading after controlling IQ, age, gender and socioeconomic status, with only a weak and statistically marginal association with lexical processing. With biosocial variables and phonological awareness partialled out, higher order language was unrelated to lexical aspects of reading. These data highlight the multicomponential nature of reading and suggest that different measures of reading cannot simply be regarded as interchangeable measures of a single undifferentiated reading construct.