[Does intelligence make a difference? Spelling and phonological readiness in specific and nonspecific...

In an investigation involving, 1800 second-to-fourth graders, the children were divided into three groups according to their reading and spelling achievement and the results of a nonverbal intelligence test: children with average achievement in oral reading and spelling, and those with poor achievements in both which were either discrepant or non-discrepant to their good-to-average scores on the intelligence test.

Results for all three groups on a number of spelling tests were compiled to assess two component spelling skills: phonological recoding and application of orthographical knowledge.

Children with either specific or nonspecific reading and spelling disabilities performed at the same level of phonological recoding, while both groups were worse than younger children of average ability at the same spelling level. Children with IQ-discrepant reading and spelling disabilities hat, on the other hand, a certain advantage over children with the same number of difficulties in spelling but a lower IQ on tasks requiring a knowledge of orthography. Though particularly evident in the lower grades, this advantage declined with advancing grade level. Additional comparison of the three groups in tests of phonological awareness and other phonological skills revealed a similar pattern of great differences between the two groups of poor readers and spellers and the average children, but slight non-significant differences between children with IQ-discrepant and non-discrepant reading and spelling disabilities.