Validation of the Center for Epidemiologic Studies Depression Scale in screening for major depressive disorder among retired firefighters exposed to the World Trade Center disaster

Background: We evaluated the performance of a modified Center of Epidemiologic Studies Depression Scale (CES-D-m), which captured symptoms in the past month, in comparison to the Diagnostic Interview Schedule (DIS) in identification of major depressive disorder (MDD) in World Trade Center (WTC)-exposed retired Fire Department, City of New York (FDNY) firefighters. Methods: From 12/2005 to 7/2007, FDNY enrolled retired firefighters in its Medical Monitoring and Treatment Program. All participants completed the CES-D-m and the DIS on the same day. Sensitivity, specificity, receiver operating characteristic (ROC) curves, and Youden's index were used to assess properties of the CES-D-m. Multivariate logistic regression analyses were also used. Results: 7% of 1915 retired male firefighters were diagnosed with MDD using the DIS. Using the most common CES-D cutoff score of 16, the prevalence of elevated risk was 36%, which declined to 23% using a cutoff score of 22, as determined by Youden's index. At 22, CES-D-m sensitivity was 0.84, specificity was 0.82, and the area under the ROC curve was 0.89 relative to DIS MDD diagnosis. Limitations: Participants were more likely than non-participants to live in the New York City area. Conclusions: This is the first study of WTC rescue/recovery workers to assess the performance of a one-month version of the CES-D. The CES-D-m performed well in identifying those at elevated risk. Since diagnostic follow-up is time consuming and costly, it is important to correctly distinguish those at elevated risk using a screening tool that has been validated in the population under study.