ADHD Assessment - Why it's Important to Get a Private ADHD Diagnosis Anyone who suspects they have ADHD but has not been diagnosed should get an ADHD assessment. The process can take up to two hours, and it's recommended to bring someone from the family or a close acquaintance along. https://andreskuagk.bloggosite.com/36423938/adhd-diagnosis-uk-private-explained-in-less-than-140-characters