Table 1.

Prevalence estimates of personality disorders in the three previous non-clinical US population studies that used validated structured interviews

	Study
	Lenzenweger et al., 1997	Samuels et al., 2002	Crawford et al., 2005
Instrument	IPDE*	IPDE*	SCID-II†
Nomenclature	DSM-III-R	DSM-IV	DSM-IV
Location	Ithaca, NY USA	Baltimore, MD USA	Upstate New York, USA
Sample	University students	Community sample	Community sample
Cluster A
Paranoid	1.0	0.7	5.1
Schizoid	1.0	0.9	1.7
Schizotypal	1.6	0.6	1.1
Cluster B
Antisocial	0.6	4.1	1.2‡
Borderline	1.3	0.5	3.9
Histrionic	2.9	0.2	0.9‡
Narcissistic	2.7	0.0	2.2
Cluster C
Avoidant	1.0	1.8	6.4
Dependent	0.6	0.1	0.8
Obsessive-Compulsive	1.3	…§	4.7
Passive-Aggressive	1.6	…§	…§
Any PD	11.0∥	9.0	15.7
(n)	(1646/258)¶	(742)	(644)

^*International Personality Disorder Examination (IPDE) DSM-III-R (Loranger et al 1994) and DSM-IV (Loranger 1999) versions

^†Structured Clinical Interview for DSM-IV Axis II Disorders (SCID-II) (First et al 1994)

^‡Antisocial PD and histrionic PD prevalence estimates were based on self-report data.

^§Ellipses indicate not applicable

^∥Includes DSM-III-R sadistic PD as well as personality disorder “not otherwise specified” based on the IPDE

^¶A two-stage case identification approach was used in which all 1,646 respondents were administered screening questions based on the IPDE and all screened positives plus a probability sample of screened negatives were administered the IPDE (n = 258).