Reliability and factor structure of the Brief Symptom Inventory (BSI) in adults

Psychometric properties of the Brief Symptoms Inventory, (B.S.I., Derogatis & Melisaratos, 1983) were studied in a sample of 743 adults, whose children demanded psychological treatment. The investigation analyzes the natural dimension of the inventory and the internal consistency of the whole scale as well as the nine subscales which compose the analyzed instrument. The results of the main component’s first and second order factor analyses (varimax rotation) show that the B.S.I. measure a one-dimensional construct of general psychological distress with an excellent reliability (α=0.990). The Cronbach alpha coefficients of the subscales are good: they ranged from a low on the phobic anxiety dimension (α= 0.876) to a high on the somatization (α= 0.960).