Personality Diagnostic Questionnaire

People in prison: (Davison et al., 2001; N = 389; median age = 31 years; United Kingdom)

• Davison et al. found a cut-off score of 25 to be more sensitive and specific than the recommended cut-off score of 50:

Persons living in residential substance abuse treatment programs and prisons: (Guy et al., 2008; N = 1,345; Mean Age (SD) = 31.40 [6.69] years; gender = 83% men [n = 1,122], 17% women [n = 223]; race/ethnicity = 66% Caucasian [n = 869], 34% African American [n = 454], 10% Hispanic ethnicity; incarcerated = 50.4% [n = 678], substance use residential facility = 49.6% [n = 667]).

• For the Antisocial Personality Disorder subscale, participants needed to endorse at least three items that evaluated conduct disorder criteria and four items that evaluated adult criteria. These cut-off scores led to sensitivity of 50% and specificity of 84%.

People in prison: (Green & Browne, 2019; N = 37; mean age [SD] = 33.38 [10.93] years; Men in prison; convicted of domestic violence)

• 80% of participants had clinically significant scores on at least one portion of the Trauma Symptom Inventory, indicating that the participants experienced posttraumatic symptoms in the previous six months.
• 65% of participants met PDQ-4+ criteria for Antisocial Personality Disorder or Borderline Personality Disorder.

53% of participants met PDQ-4+ criteria for both Antisocial Personality Disorder and Borderline Personality Disorder.

Persons living in residential substance abuse treatment programs and prisons: (Guy et al., 2008; N = 1,345; Mean Age (SD) = 31.40 [6.69] years; gender = 83% men [n = 1,122], 17% women [n = 223]; race/ethnicity = 66% Caucasian [n = 869], 34% African American [n = 454], 10% Hispanic ethnicity; incarcerated = 50.4% [n = 678], substance use residential facility = 49.6% [n = 667]).

• Participants reported a mean of 7.98 (SD = 4.65) symptoms on the ASPD portion of the PDQ-4+.
• 34% of participants (n = 456) were classified with ASPD.
• Men scored significantly higher than women (t[1343] = 2.12, p = 0.03; Cohen’s d = 0.16).
• No significant differences were found between race/ethnicity (t[1321] = 1.93, p =  0.05; Cohen’s d = 0.11).
• The residential sample scored significantly higher than incarcerated sample (t[1343] = 4.00, p < 0.01; Cohen’s d = 0.22).

People in prison: (Green & Browne, 2019; N = 37; mean age [SD] = 33.38 [10.93] years; men in prison; convicted of domestic violence)

• Excellent internal consistency for overall scale: Cronbach’s alpha = 0.86.
• Adequate internal consistency for Borderline subscale: Cronbach’s alpha = 0.79.
• Adequate internal consistency for Antisocial subscale: Cronbach’s alpha = 0.70.
• Poor internal consistency for remainder of subscales: Cronbach’s alpha < 0.70.

Persons living in residential substance abuse treatment programs and prisons: (Guy et al., 2008; N = 1,345; Mean Age (SD) = 31.40 [6.69] years; gender = 83% men [n = 1,122], 17% women [n = 223]; race/ethnicity = 66% Caucasian [n = 869], 34% African American [n = 454], 10% Hispanic ethnicity; incarcerated = 50.4% [n = 678], substance use residential facility = 49.6% [n = 667]).

• Excellent internal consistency for Antisocial subscale: Cronbach’s alpha = 0.85, MIC = 0.20.

The PDQ-4+ is composed of scales aimed to measure personality disorder diagnoses by using the diagnostic criteria from the DSM-IV, which contains the information required to meet each specific criterion. The test includes all of the personality disorders within the DSM-IV, the latest DSM when the PDQ-4+ was developed (Green & Browne, 2019).

Mixed Psychiatric Sample: (Fossati et al., 1998; N = 300; Mean age [SD] = 30.38 [9.16]; Gender = 59.3% female [n = 178], 40.7% male [n = 122])

• All scales have provided a significant amount of false-positives other than the Narcissistic Personality Disorder subscale.

Mixed Psychiatric Sample: (Fossati et al., 1998; N = 300; Mean age [SD] = 30.38 [9.16]; Gender = 59.3% female [n = 178], 40.7% male [n = 122])

• Poor internal consistency (mean KR-20 = .61).

Mixed Psychiatric Sample (Fossati et al., 1998; N = 300; Mean age (SD) = 30.38 (9.16); Gender = 59.3% female [n = 178], 40.7% male [n = 122])

• Correlations between PDQ-4 and SCID-II scores:

Hopwood et al. found that there may be some limitations for the PDQ-4’s content validity when assessing Narcissistic Personality Disorder: “The PDQ-4 only includes a single binary item to capture each DSM-IV symptom, potentially limiting the reliability and content validity of the measure” (Hopwood et al., 2012, p. 281).

 Undergraduate Students: (Fossati et al., 2004; N = 747; mean age = 22.96 [SD = 2.63] years; mean university education = 3.89 [SD = 1.97] years; gender = 64.5% female [n = 482], 35.5% male [n = 265]; Italy)

• Mean number of Borderline Personality Disorder symptoms = 3.08; SD = 1.95
• Mean number of Antisocial Personality Disorder symptoms = 1.32; SD = 1.45
• Female participants scored significantly higher on the BPD scale than male participants; t(745) = 3.20, p < 0.005.
• Female participants scored significantly lower on the ASPD scale than male participants; t(745) = -3.94, p < 0.001.

Undergraduate Students (Okada & Oltmanns, 2009; N = 203; mean age [SD] = 20 [1.1] years; 31% male [n = 63]; United States):

Undergraduate students (Ling et al., 2010; N = 4,811; China)

Undergraduate students (Ling et al., 2010; N = 4,811; China)

Community residents (Ling et al., 2010; age range = 18-80 years; general community residents, China)

Predictive Validity:

Undergraduate students, China  (Ling et al., 2010; N = 313):

• Poor PPM correlations between personality disorder scores, as measured by the PDQ-4+, and parental relationships in childhood, as measured by the CECA.Q.
• Adequate correlations between total score for PDQ and antipathy toward mother and total score for PDQ and antipathy toward father.

Convergent Validity:

Undergraduate students (Okada & Oltmanns, 2009; N = 203; 69% female; mean age [SD] = 20 [1.1]; United States):