Screening tools used for measuring depression among people with Type 1 and Type 2 diabetes: a systematic review

Background Depression is common in patients with Type 1 or Type 2 diabetes, has a strong negative impact on the quality of life of patients and is associated with poor outcomes and higher mortality rates. Several guidelines encourage screening of patients with diabetes for depression. It is unclear which depression screening tools are currently being used in people with diabetes and which are most appropriate. Methods A systematic review was conducted to examine which depression screening instruments are currently being used in diabetes research, and the operating characteristics of these tools in diabetes populations. Literature searches for the period January 1970 to October 2010 were conducted using MEDLINE, PSYCH-INFO, ASSIA, SCOPUS, ACADEMIC SEARCH COMPLETE, CINAHL and SCIENCE DIRECT. Results Data are presented for the 234 published studies that were examined. The Beck Depression Inventory and the Centre for Epidemiologic Studies Depression Scale were the most popular screening tools (used in 24% and 21% of studies). Information on the cultural applicability of screening tools was mostly unavailable and, where reported, included only details of the language translation process. A small number of studies reported reliability data, most of which showed moderategood sensitivity and specificity but a high rate of false positives. Conclusions Although a range of depression screening tools have been used in research, there remains few data on their reliability and validity. Information on the cultural applicability of these instruments is even scantier. Further research is required in order to determine the suitability of screening tools for use in clinical practice and to address the increasing problem of co-morbid diabetes and depression.