Association results from logistic regression analysis between reading/spelling difficulties and ADHD symptoms measured by the SDQ-hyperactivity/inattention score.

1<p>refers to the number of individuals with reading/spelling difficulties for whom full phenotypic information was available and who were included in regression analysis.</p>2<p>refers to the number of individuals without reading/spelling difficulties for whom full phenotypic information was available and who were included in regression analysis.</p>3<p>adjusted for gender, age, study and study center.</p>4<p>additional adjustment for parental education, age of mother at birth, daily TV/PC use, single parent and ETS exposure.</p><p>p-values <0.05 are depicted in bold.