ADHD is associated with an increased risk of written-language disorder
What is the incidence of written-language disorder (WLD), with and without reading disability (RD), among children with and without attention-deficit/hyperactivity disorder (ADHD)?
5699 children born between 1st January 1976 and 31st December 1982 in one school district, who still lived in the area after age 5 years, and who did not have clinical diagnoses of severe intellectual disability or full-scale IQ scores <50.
Rochester, Minnesota, USA; participants born from 1976 to 1982.
Children were assessed for ADHD, WLD and RD retrospectively from birth until death, emigration or graduation using school and medical records. Individuals with ADHD had to meet DSM-IV criteria of ADHD; have positive ADHD questionnaire results; or have a clinical diagnosis of ADHD. The date of ADHD diagnosis was either when clinical diagnosis was made, or in its absence the date of the first positive ADHD specific questionnaire or the date when DSM-IV research criteria were met. WLD and RD were diagnosed by comparing writing or reading achievement scores with cognitive ability test results. WLD or RD were diagnosed if the standard score at any time point was >1.75 SD below the standard score predicted by an IQ test; the difference between the achievement scores and IQ scores was …