American Journal of Educational Research
ISSN (Print): 2327-6126 ISSN (Online): 2327-6150 Website: Editor-in-chief: Ratko Pavlović
Open Access
Journal Browser
American Journal of Educational Research. 2013, 1(1), 22-25
DOI: 10.12691/education-1-1-5
Open AccessArticle

Prevalence and Gender Ratio of Dyslexia in Greek Adolescents and Its Association with Parental History and Brain Injury

F. Vlachos1, , E. Avramidis1, G. Dedousis2, M. Chalmpe1, I. Ntalla2 and M. Giannakopoulou3

1Department of Special Education, University of Thessaly, Volos, Greece

2Department of Nutrition and Dietetics, Harokopio University, Athens, Greece

3Department of Nursing, National and Kapodistrian University of Athens, Athens, Greece

Pub. Date: January 28, 2013

Cite this paper:
F. Vlachos, E. Avramidis, G. Dedousis, M. Chalmpe, I. Ntalla and M. Giannakopoulou. Prevalence and Gender Ratio of Dyslexia in Greek Adolescents and Its Association with Parental History and Brain Injury. American Journal of Educational Research. 2013; 1(1):22-25. doi: 10.12691/education-1-1-5


Dyslexia is the most common and carefully studied of the learning disabilities in school-age children. It is characterized by a marked impairment in the development of reading skills, and affects a large number of people. The prevalence of dyslexia shows considerable cross-national variation. Additionally, a plethora of research studies have indicated that there are more boys than girls with reading difficulties. The aim of this study was to identify the frequency and gender ratio of dyslexia in a sample of Greek adolescents and their siblings. 598 secondary school students (Mean age 13.33, SD = 1.49) who attended mainstream public schools participated in this study. The prevalence of dyslexia in this study was estimated at 5.52%, a finding consistent with the data from other countries with “pure” orthographies. Statistical analysis revealed significant differences in the prevalence of dyslexia between gender (7.6% male, 3.8% female), which means that boys were twice as likely to be identified as dyslexic than their female peers. Additionally, statistically significant differences were observed between dyslexics who had a parent suffering from dyslexia (15.1%), compared to normal readers (1.8%), but no differences were observed between the two groups as for the frequency of brain injuries. Overall, our findings are in accordance with the results of previous national studies indicating the universal existence and the biological basis of this developmental disability.

Dyslexia Prevalence Gender

Creative CommonsThis work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit


Figure of 3


[1]  Shastry, B., “Developmental dyslexia: An update,” Journal of Human Genetics, 52, 104–109, 2007.
[2]  Vlachos, F., “Dyslexia: A synthetic approach to causal theories,” Hellenic Journal of Psychology, 7, 205-240, 2010.
[3]  Pennington, B., Diagnosing learning disorders: A neuropsychological framework ( 2nd ed.)., Guilford Press, New York, 2009.
[4]  Coltheart, M. & Prior, M., Learning to read in Australia. Canberra: Academy of the Social Sciences in Australia., 2007.
[5]  Katusic, S., Colligan, R., Barbaresi, W., Schaid, D. & Jacobsen, S., “Incidence of reading disability in a population-based birth cohort 1976-1982,” Mayo Clinic Proceedings, 76, 1081-1092, 2001.
[6]  Prior, M., Samson, A., Smart, D. & Oberklaid, F., “47, 32-37, 1995.
[7]  Sofie, C. & Riccio, C., “A comparison of multiple methods for the identification of children with reading disabilities,” Journal of Learning Disabilities, 35, 234-244, 2002.
[8]  Wheldall, K., & Limbrick, L., “Do more boys than girls have reading problems?,” Journal of Learning Disabilities, 43, 418-429, 2010.
[9]  Limbrick, L., Wheldall, K., & Madelaine, A., “Gender ratios for reading disability: Are there really more boys than girls who are low-progress readers?,” Australian Journal of Learning Difficulties, 13, 161 – 179, 2008.
[10]  Miles, T., Haslum, M., & Wheeler, T., “Gender ratio in dyslexia,” Annals of Dyslexia, 48, 27-55, 1998.
[11]  Shaywitz, S., Shaywitz, B., Fletcher, J., Escobar, M., “Prevalence of reading disability in boys and girls: Results of the Connecticut longitudinal study,” Journal of the American Medical Association, 264, 998–1002, 1990.
[12]  Siegel, L., Smythe, I., “Reflections on research on reading disability with special attention to gender issues,” Journal of Learning Disabilities, 38, 473-477, 2005.
[13]  Apostolara, P., Tsoumakas, K., Diomidous, M., & Kalokerinou, A., “The Correlation between Dyslexia and Social and Demographic Factors in Children of School Age,” Nosileftiki, 49, 164–173, 2010.
[14]  Vellutino, F., Fletcher, J., Snowling, M., & Scanlon, D., “Specific reading disability (dyslexia): What have we learned in the past four decades?,” Journal of Child Psychology and Psychiatry, 45, 2-40, 2004.
[15]  Vlachos, F., “Η γενετική βάση της δυσλεξίας: Σύγχρονα ευρήματα και μελλοντικές προοπτικές. [The genetic basis of dyslexia: Current findings and future perspectives (in Greek)]”. In P. Orfanos (Ed.) The special education in the society of knowledge, Grigoris Publications, Athens, Greece, 2007, 132-141.
[16]  Tallal, P., Ross, R. & Gurtiss, S., “Unexpected sex-ratios in families of language/learning impaired children,” Neuropsychologia, 27, 987-998, 1989.
[17]  Wadsworth, S., DeFries, J., Stevenson, J., Gilger, J., & Pennington, B., “Gender ratios among reading disabled children and their siblings as a function of parental impairment,” Journal of Child Psychology and Psychiatry, 33, 1229-1239,1992.
[18]  Snowling MJ, Muter V, Carroll J, “Children at family risk of dyslexia: a follow-up in early adolescence,” J Child Psychol Psychiatr 48, 609–618, 2007.
[19]  Flannery, K., ., . & ., “Male prevalence for reading disability is found in a large sample of black and white children free from ascertainment bias,” 6, 433-442, 2000.
[20]  Liederman, J., Kantrowitz, L., & Flannery, K., “Male vulnerability to reading disability is not likely to be a myth: A call for new data,” Journal of Learning Disabilities, 38, 109−129, 2005.