Introduction

Personality disorder not otherwise specified (PDNOS) is a diagnostic classification for some DSM-IV Axis II personality disorders not otherwise listed in DSM-IV.

The DSM-5 does not have an equivalent to Personality Disorder NOS. However Personality disorder-trait specified (PD-TS) remains under consideration for future revisions. The DSM 5 “Unspecified Disorder” is not a personality disorder, it is used to enhance specificity of an existing disorder or it is an emergency diagnosis unto itself (i.e. Unspecified Mental Disorder, 300.9), without being attached to another disorder.

Not to be confused with PDD-NOS (Pervasive Developmental Disorder Not Otherwise Specified).

Diagnostic Criteria

DSM-IV-TR

This diagnosis may be given when no other personality disorder defined in the DSM fits the patient’s symptoms.

Four personality disorders were excluded from the main body of the DSM-IV-TR but this diagnosis may be used instead. The four excluded personality disorders are:

• Sadistic personality disorder.
• Self-defeating personality disorder.
• Depressive personality disorder.
• Passive-aggressive personality disorder.

It is a requirement of DSM-IV that a diagnosis of any personality disorder also satisfies a set of Diagnostic criteria.

ICD-10

The World Health Organisation’s ICD-10 defines a conceptually similar disorder to “personality disorder not otherwise specified” called (F60.9) Personality disorder, unspecified.

It is a requirement of ICD-10 that a diagnosis of any personality disorder also satisfies a set of Diagnostic criteria.

Epidemiology

In one study, PDNOS was found to be the third most frequent personality disorder diagnosis.