Identifying palliative care patients with symptoms of depression: an algorithm.

INTRODUCTION Even though depression has serious and wide-ranging effects on outcomes in palliative care, errors in the identification of depressed patients are common. OBJECTIVES To examine the clinical validity of widely publicised one- and two-question screening tools for depression in two palliative care settings. Also, to examine the construct validity and acceptability of a new empirically derived algorithm. METHOD Participants were Australian palliative care patients in an inpatient hospice (n=22) or the community (n=69). Patients completed an unstructured interview about their feelings, questions relevant to three reference standards, two screening questions for depression and questions about the acceptability of the screening questions. RESULTS The clinical validity of the one- and two-question screening tools did not generalise across the two care settings. In contrast, the algorithm met stringent criteria for clinical validity for two reference standards in both settings. The algorithm also selectively identified patients whose unstructured interviews referred to themes consistent with depression. The algorithm includes potentially sensitive questions about anhedonia and depressed affect. However, almost all patients and staff reported that asking such questions soon after referral was acceptable. CONCLUSIONS A four-question algorithm designed to identify patients who warrant follow-up for depression showed clinical validity, generalizability and construct validity, and the content was acceptable to patients and clinicians.