A comparative study of two scoring methods for screening for depression with the Brief Depression Scale

The screening characteristics (sensitivity and specificity) of a ten-item self-rated depression scale, the Brief Depression Scale (BDS), were assessed according to two different scoring mechanisms in a hospital sample of 275 patients with depressive illness and anxiety disorders and a non-clinical sample of 50 subjects. The first scoring method was 'conventional' in using the BDS total score and the second scoring method was to count the number of items on the BDS where the individual item scores were greater than a certain 'threshold' score. There was a very high likelihood of fulfilling the closest corresponding ICD-10 (International Statistical Classification of Mental and Behavioural Disorders, 10th revision) or DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) diagnostic criterion to a specific BDS item at an item score of 4 points. The sensitivity and specificity of the BDS in detecting a case of ICD-10 or DSM-IV depression were both 85% if four or more items scored above this level (4 points per item). These values compared favourably to those obtained at the conventional BDS 'cut-off' score of 19 points (sensitivity 87% and specificity 90%). The novel scoring mechanism might offer the advantages of a reduced assessment time after screening.