In addition to subthreshold (personality difficulty) and single cluster (simple personality disorder), this also derives complex or diffuse personality disorder (two or more clusters of personality disorder present) and can also derive severe personality disorder for those of greatest risk. There are several advantages to classifying personality disorder by severity:
It not only allows for but also takes advantage of the tendency for personality disorders to be comorbid with each other. It represents the influence of personality disorder on clinical outcome more satisfactorily than the simple dichotomous system of no personality disorder versus personality disorder. This system accommodates the new diagnosis of severe personality disorder, particularly "dangerous and severe personality disorder" (DSPD). Effect on social functioning
Social function is affected by many other aspects of mental functioning apart from that of personality. However, whenever there is persistently impaired social functioning in conditions in which it would normally not be expected, the evidence suggests that this is more likely to be created by personality abnormality than by other clinical variables. The Personality Assessment Schedule gives social function priority in creating a hierarchy in which the personality disorder creating the greater social dysfunction is given primacy over others in a subsequent description of personality disorder. Attribution
Many who have a personality disorder do not recognize any abnormality and defend valiantly their continued occupancy of their personality role. This group have been termed the Type R, or treatment-resisting personality disorders, as opposed to the Type S or treatment-seeking ones, who are keen on altering their personality disorders and sometimes clamor for treatment.
To perform the test, the examiner grasps and ulnar deviates the hand when the person has their thumb held within their fist. If sharp pain occurs along the distal radius (top of forearm, about an inch below the wrist), de Quervains syndrome is likely. While a positive Finkelsteins test is often considered pathognomonic for de Quervain syndrome, the maneuver can also cause pain in those with osteoarthritis at the base of the thumb. Differential diagnosis
Differential diagnoses include:

Osteoarthritis of the trapezio-metacarpal joint
Intersection syndrome—pain will be more towards the middle of the back of the forearm and about 2–3 inches below the wrist, usually with associated crepitus. Wartenbergs syndrome: The primary symptom is paresthesia (numbness/tingling). Treatment
As with many musculoskeletal conditions, the management of de Quervains disease is determined more by convention than scientific data. A systematic review and meta-analysis published in 2013 found that corticosteroid injection seems to be an effective form of conservative management of de Quervains syndrome in approximately 50% of patients, although more research is needed regarding the extent of any clinical benefits. Efficacy data are relatively sparse and it is not clear whether benefits affect the overall natural history of the illness. One of the most common causes of corticosteroid injection failure are subcompartments of the extensor pollicis brevis tendon.Most tendinoses are self-limiting and the same is likely to be true of de Quervains although further study is needed.Palliative treatments include a splint that immobilized the wrist and the thumb to the interphalangeal joint and anti-inflammatory medication or acetaminophen.