How Much Does A Private ADHD Diagnosis Cost? You might need to take the private option if you are an adult who suffers from ADHD. This is a good option since private psychiatrists are more experienced in diagnosing people with ADHD. They will also screen for co-morbidities such as anxiety http://www.stes.tyc.edu.tw/xoops/modules/profile/userinfo.php?uid=1558303