Abstract
Background: Difficulties with aspects of literacy are often seen in children with autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (AD/HD). The bases of the connections between these disorders and literacy difficulties are poorly understood. Furthermore, it is not clear if existing research is representative for girls.
Aims: There were three aims: (1) to compare performance in reading comprehension, word decoding, and spelling in girls with ASD (n = 20), AD/ HD (n = 36), and community girls with typical developing (girls; n = 54); (2) to assess rates of reading and writing disorders within groups; and (3) to examine the predictive value of measures of autistic and AD/HD symptomatology to reading comprehension in the whole girl sample.
Methods & Procedures: Participants were aged between 8 and 17 years, and had a full scale IQ>70. Standardized tests of literacy, oral vocabulary, and non-verbal ability were administered. Parent ratings of degree of autistic symptomatology and both parent and teacher ratings of AD/HD symptomatology were collected for all girls.
Outcomes & Results: Girls with diagnosed ASD could not be separated significantly from typically developing girls or girls with AD/HD on average performance on any literacy test. However, among girls with ASD, 40% had at least one reading and writing disorder. Girls with AD/HD performed lower than typically developing girls in reading comprehension, word decoding, and spelling, and 56% had at least one reading and writing disorder. In regression analysis, using the total sample, both degrees of autistic and AD/HD symptomatology negatively contributed to the variance in reading comprehension after controlling for oral vocabulary, word decoding, and non-verbal ability. Whereas AD/HD contributed to the variance in reading comprehension once autistic symptomatology was controlled for, the opposite was not true. However, a large bivariate correlation between autistic and AD/HD symptomatology somewhat complicates the interpretation of that result.
Conclusions & Implications: The findings highlight the importance of monitoring and supporting the literacy development in girls with ASD or AD/HD. Results from regression analyses suggested that word decoding and/or oral vocabulary training may not be sufficient for the girls fully to overcome difficulties in the important skill of reading comprehension.
Acknowledgements
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
Notes
1. Differences in average performance on the literacy measures between girls with AD/HD and TYP girls were also evaluated with full-scale IQ and oral vocabulary as covariates using parametric analyses of covariance (ANCOVAs). The differences for spelling and word decoding remained in these analyses, but reading comprehension just failed to reach statistical significance (p = 0.055, two-tailed).