Screening for distress and depression in cancer patients: is ultrashort depression screening a valid measure in the UK? A prospective validation study.

This study sought to validate the two-question (2Q) depression screen as a screening tool for psychological distress and depression against four criterion measures (Hospital Anxiety and Depression Scale [HADS], General Health Questionnaire-12, Brief Symptom Inventory-18 [BSI-18], and the distress thermometer) for a UK cancer population. We used a prospective cross-sectional study design. A consecutive sample of 399 outpatients from four outpatient oncology clinics and a palliative care day center in North London were initially identified. Of these, 249 were eligible, of whom 171 consented to take part. Data were analyzed using receiver operating characteristic analysis to examine the sensitivity and specificity of the 2Q depression instrument against the cutoff scores already shown to demonstrate clinically significant symptoms ("caseness") in the criterion measures. Sensitivity and specificity, with 95% confidence intervals, were calculated in addition to positive and negative predictive values. The 2Q depression screen showed sensitivity of 68%-89% and specificity of 70%-84% when compared with our four criterion measures in screening for psychological distress; its best performance was against the HADS (89% sensitivity and 79% specificity). In screening for depression, the 2Q depression screen showed sensitivity of 84%-94% and specificity of 72%-73% when compared with our two criterion measures, its best performance being against the BSI depression subscale (94% sensitivity and 72% specificity). Our study demonstrated that the 2Q depression screen showed good psychometric properties, which further supports its usefulness as a simple instrument in screening for psychological distress in cancer patients in the UK.