Journal of Speech, Language, and Hearing Research, februari 2016:

The empirical record regarding the expected co-occurrence of attention-deficit/hyperactivity disorder (ADHD) and specific language impairment is confusing and contradictory.  The best option for measuring core language impairments in a manner that does not potentially penalize individuals with ADHD is to focus assessment on key grammatical and verbal memory skills. Likewise, assessment of ADHD symptoms through standardized informant rating scales is optimized when they are adjusted for overlapping language and academic symptoms.