Screening for psychological distress in palliative care: a systematic review

Psychological distress is common in the terminally ill. It is often underdetected and undertreated and has significant impact on the individual and family. There is a growing consensus on a broader concept of psychological suffering conceptualized as "distress" in the palliative care setting. Psychological screening programs play an important role in improving detection and management of distress. National and international guidelines recommend routine screening. This systematic review summarizes the evidence for screening for psychological distress in a palliative care setting. The review includes studies that compare screening questionnaires against a gold standard criterion of semistructured or structured psychiatric interview. Eight studies were identified which examined the performance of 10 screening questionnaires, ranging from single items to multidimensional questionnaires with up to 33 items. The performances of these questionnaires are described in terms of their sensitivity, specificity, and positive and negative predictive values. There are very few studies that examine the validity of questionnaires against credible criteria such as psychiatric interview and most studies have so far focused on depression. Unidimensional scales appear to perform equally well compared to the longer versions. This review summarizes the evidence, the quality of this evidence, and future challenges to improve identification and management of distress in palliative care.