The Borderline Syndrome Index: a Validation Study using the Personality Assessment Schedule

BACKGROUND: This study examines the validity and screening properties of the Borderline Syndrome Index--BSI (developed in the USA) for categories of the Personality Assessment Schedule--PAS (developed in the UK). METHOD: Patients were recruited by case control sampling. Chance corrected agreement between instruments and screening properties of the BSI were calculated. RESULTS: The BSI proved a moderately sensitive but non-specific screen. Questionnaire scores were highly correlated with symptom measures. CONCLUSIONS: The results do not support the validity of the BSI or its use as a screening instrument. BSI scores may be distorted by current symptoms.