The Depression Scale as a screening instrument for a subsequent depressive episode in primary healthcare patients.
BACKGROUND
There are numerous instruments for screening for depression. A feasible screen is good at both recognising and predicting depression.


AIMS
To study the ability of the Depression Scale and its items to recognise and predict a depressive episode.


METHOD
A sample of patients attending primary care was examined in 1991-992 and again 7 years later. The accuracy of the Depression Scale at baseline and at follow-up was tested against the Short Form of the Composite International Diagnostic Interview (CIDI-SF) diagnosis of depression at follow-up. The sensitivity and specificity of the Depression Scale and its items were assessed.


RESULTS
Both baseline and follow-up Depression Scale scores were consistent with the CIDI-SF diagnoses. It was possible to find single items efficient at both recognising and predicting depression.


CONCLUSIONS
The Depression Scale is a useful screening instrument for depression, with both diagnostic and predictive validity.