How to Get an ADHD Assessment From a Private Provider The NHS can take months, or years to determine ADHD. This is due to the lack of specialists and the large demand for services. There are many private clinics that provide the fastest and most complete alternative to the NHS. https://private-psychiatry61802.thekatyblog.com/29088123/adhd-diagnosis-private-tips-from-the-top-in-the-business