Borderline Personality Questionnaire (BPQ).

Poreh, Rawlings, Claridge,

Freeman, Faulkner, & Shelton, (2006).

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1) Impulsivity

2) Affective

Instability.

3) Abandonment

4) Relationships

5) Self-Image

6) Suicide/ Self-Mutilation

7) Emptiness

8) Intense Anger

9) Quasi-Psychotic States.

The full BPQ is a highly reliable test. Subscale reliabilities are generally satisfactory for scales of this length, though with a few exceptions, particularly Quasi-Psychotic States. Several of the subscales show high positive skew, noting that the standard error of skew for the three samples was respectively .18, .16, and .20. No transformations were performed, and the skewness of the data should be taken into account when considering the parametric statistics reported in subsequent analyses— Poreh, Rawlings, Claridge,

Freeman, Faulkner, & Shelton. (2006).

Discriminant validity was examined in Sample 2. Pearson correlations were calculated between the BPQ sum score and the total scores on both the MMPI-2 STY subscale (r = .48) and the SPQ (r = .45). While both coefficients were highly significant, their moderate size suggests satisfactory discriminant validity for the BPQ. Convergent validity was examined by correlating the BPQ with the MMPI-2 BPD in Sample 2, yielding a high correlation of .85. The BPQ was correlated with the STB in Samples 3 and 4, yielding coefficients of .72 and .78 respectively. These results suggest high convergent validity for the BPQ—Poreh, Rawlings, Claridge, Freeman, Faulkner, & Shelton (2006).

Borderline Evaluation of Severity Over Time (BEST)

Pfohl, Blum, John, McCormick, Allen, & Black (2009).

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1) Subscale A (8 items) addresses problematic thoughts and feelings that are characteristic of

BPD (i.e., suicidal thoughts).

2) Subscale B (4 items) addresses problematic or negative behaviours (i.e., problems with impulsive behaviour). Items on these subscales are rated from 1 to 5, with 5 = extreme distress, and 1 = no

distress caused by

this symptom.

3) Subscale C, consists of three items that assess the use of positive behaviours learned in therapy (i.e., following through with therapy plans). These items are

rated based on frequency over the course of a week.

Test-retest reliability: Correlation between baseline and screening BEST total scores was moderate

(r = .62, n = 130, p < .001).

The results indicate that the instrument has good test-retest reliability. Internal consistency is excellent, as shown by the moderate to high Cronbach’s α coefficients across study visits, which argues

strongly for construct validity— Pfohl, Blum, John, McCormick, Allen, & Black (2009).

The BEST exhibits face validity by assessing thoughts and behaviours typical of BPD. Evidence for content validity has been indirectly established because the items are derived from the DSM-IV.

At the screening visit, the BEST correlated strongly with the

ZAN-BPD score, SCL-90-R total

score, the SAS total score, the CGI severity score, and both the GAS and BDI scores—Pfohl, Blum, John, McCormick, Allen, & Black (2009).