Abstract
Extensive psychometric test data were obtained from two independent samples of reading-disabled and control children: 70 probands and 75 controls tested on two occasions over an average interval of 4.2 years, and 35 probands and 22 controls tested on three occasions over an average interval of 8.6 years. When composite measures of reading performance and symbol-processing speed were subjected to mixed-model multivariate analyses of variance, significant effects due to group (reading-disabled versus control) and time (i.e., test session) were obtained in both samples, and a significant group-by-time interaction was obtained for the sample tested on three occasions. In general, rates of change in reading performance are highly similar for reading-disabled and control children. However, with regard to symbol-processing speed, differences between the two groups increase as a function of age. Although no evidence was obtained for differential longitudinal stability of either composite measure in reading-disabled and control children, results of a multiple regression analysis suggest that reading deficits during middle childhood are highly predictive of later reading problems, even into early adulthood.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Cohen, J. and Cohen, P. 1975.Applied Multiple Regression/Correlation Analysis for the Behavioral Sciences. Hillsdale, N.J.: Lawrence Erlbaum Associates.
DeFries, J. C. 1985. Colorado reading project.In D. Gray and J. Kavanagh (eds.).Biobehavioral Measures of Dyslexia. Parkton, Md.: York Press.
DeFries, J. C. and Baker, L. A. 1983. Colorado family reading study: Longitudinal analyses.Annals of Dyslexia 33:153–162.
DeFries, J. C. and Decker, S. N. 1982. Genetic aspects of reading disability: A family study.In R. N. Malathesha and P. G. Aaron (eds.).Reading Disorders: Varieties and treatments. New York: Academic Press.
DeFries, J. C., Plomin, R., Vandenberg, S. G., and Kuse, A. R. 1981. Parent-offspring resemblance for cognitive abilities in the Colorado Adoption Project: Biological, adoptive, and control parents and one-year-old children.Intelligence 5:245–277.
DeFries, J. C., Vogler, G. P., and LaBuda, M. C. 1986. Colorado Family Reading Study: An overview.In J. L. Fuller and E. C. Simmel (eds.).Behavior Genetics: Principles and applications II. Hillsdale, N.J.: Lawrence Erlbaum Associates.
Dunn, L. M. and Markwardt, F. C. 1970.Examiner’s Manual: Peabody Individual Achievement Test. Circle Pines, Minn.: American Guidance Service.
Finucci, J. M. 1986. Follow-up studies of developmental dyslexia and other learning disabilities.In S. D. Smith (ed.).Genetics and Learning Disabilities. San Diego, Calif.: College-Hill Press.
LaBuda, M. C. and DeFries, J. C. in press. Cognitive abilities in reading-disabled and control children: A follow-up study.Journal of Learning Disabilities.
Schonhaut, S. and Satz, P. 1983. Prognosis for children with learning disabilities: A review of follow-up studies.In M. Rutter (ed.).Developmental Neuropsychiatry. New York: Guilford Press.
Wechsler, D. I. 1974.Examiner’s Manual: Wechsler Intelligence Scale for Children—Revised. New York: The Psychological Corporation.
Author information
Authors and Affiliations
Additional information
This work was supported in part by a program project grant from the NICHD (HD-11681). The invaluable contributions of staff members of the many Colorado school districts and of the families who participated in the study are gratefully acknowledged.
Rights and permissions
About this article
Cite this article
DeFries, J.C. Colorado reading project: Longitudinal analyses. Annals of Dyslexia 38, 120–130 (1988). https://doi.org/10.1007/BF02648251
Issue Date:
DOI: https://doi.org/10.1007/BF02648251