Assessment of depression severity with the PHQ-9 in cancer patients and in the general population

The Patient Health Questionnaire PHQ-9 is a widely used instrument to screen for depression in clinical research. The first aim of this study was to psychometrically test the PHQ-9 in a large sample of cancer patients. The second aim was to calculate unbiased estimates of the depression burden for several cancer groups taking into account age and gender distributions.A sample of 2,059 cancer patients with varying diagnoses were examined in this...