Brief Introduction to the Borderline Evaluation of Severity Over Time (BEST):
The Borderline Evaluation of Severity Over Time (BEST) is a 15-item measure used to test for borderline personality symptoms. This measure was developed for use as a self-report questionnaire to assess the severity of and change in borderline personality symptoms over the course of treatment.
Description of the BEST:
The BEST was developed by Bruce Pfohl, MD and colleagues at the University of Iowa, and consists of three subscales. The first two subscales (A and B) are based on the DSM-IV criteria for borderline personality disorder (BPD). Subscale A (8 items) addresses problematic thoughts and feelings that are characteristic of BPD (i.e., suicidal thoughts), while subscale B (4 items) addresses problematic or negative behaviors (i.e., problems with impulsive behavior). Items on these subscales are rated from 1 to 5, with 5 = extreme distress, and 1 = no distress caused by this symptom.
The third subscale of the BEST, subscale C, consists of three items that assess the use of positive behaviors learned in therapy (i.e., following through with therapy plans). These items are rated based on frequency over the course of a week.
Scoring the BEST:
Subscale scores are derived by adding the scores of the individual items in subscales A and B. The total frequency of the behaviors described in subscale C is then computed and subtracted from the summed scores for subscales A and B to arrive at the total scale score.
Uses for the BEST
The BEST is a useful tool for tracking the severity of BPD symptoms in patients over the course of treatment. The BEST was designed to be a easy-to-administer self-rating scale that can be completed quickly by patients with BPD during weekly therapy sessions. Data from the BEST can be used to track progress in therapy.
Reliability and Validity of the BEST
The BEST has demonstrated good internal consistency and moderate test-retest reliability. It has also demonstrated convergent validity with another widely used measure of BPD symptoms, suggesting that it measures the symptoms most characteristic of BPD. The BEST also shows sensitivity to clinical change, suggesting that it can be used to detect changes in symptoms due to treatment.
Pfohl B, Blum N, St John D, McCormick B, Allen J, Black DW. "Reliability and Validity of the Borderline Evaluation of Severity Over Time (BEST): a Self-Rated Scale to Measure Severity and Change in Persons with Borderline Personality Disorder." Journal of Personality Disorders; 23(3):281-293, 2009.