Abstract
The concept of specific reading retardation assumes that there exists a stable group of under-achieving children whose classification is not simply age- or test-specific. This assumption was investigated longitudinally in a large sample of New Zealand children who were followed from age 7 to age 11 . Substantial overlap was found between groups classified as specific reading retarded at ages 7, 9, and 11 on the basis of Burt reading and WISC-R Performance 1Q scores. At age 11, there was also substantial agreement between classifications based on three separate measures of reading achievement, although there was evidence of test-specific factors unique to comprehension- versus word recognition-based classifications. Agreement between classifications at age I1 based on WISC-R Performance 1Q and Fullscale IQ was high. The data indicated the existence of a fairly stable group of children characterised by enduring under-achievement in reading throughout the primary years of schooling.