Background: The Hamilton scale, applied by an external evaluator and the self rating Beck inventory for depression, can give discrepant results in psychiatric patients with depression. Aim: To compare depression scores obtained with the Hamilton scale and the Beck inventory in general medical patients. Patients and methods: Patients attending an outpatient clinic of a University Hospital were studied. Clinical psychiatric diagnoses were based on DSM-III. Hamilton scale was applied to 100 patients and 80 answered the Beck depression inventory. Results: Patients with major depression obtained the higher scores with both scales. However, Beck inventory had false positive and false negative results. Moreover, some patients overstated their depressive symptoms. Conclusions: self assessment of depression can be distorted by anxiety and somatic symptoms. (Rev Méd Chile 2001; 129: 627-33)