Screening for mental disorders in cancer patients – discriminant validity of HADS and GHQ‐12 assessed by standardized clinical interview

The detection and classification of comorbid mental disorders has major implications in cancer care. Valid screening instruments for different diagnostic specifications are therefore needed. This study investigated the discriminant validity of the German versions of the Hospital Anxiety and Depression Scale (HADS) and the General Health Questionnaire (GHQ‐12). A total of 188 cancer patients participated in the examination, consisting first of the assessment of psychological distress and, second, of the diagnosis of mental disorders according to DSM‐IV by clinical standardized interview (CIDI). Discriminant validity of the two instruments regarding the diagnosis of any mental disorder, anxiety, depression and multiple mental disorders was compared using ROC analysis. Overall, the total HADS scale shows a better screening performance than the GHQ‐12, especially for the detection of depressive and anxiety disorders. Best results are achieved for depressive disorders with an area under the curve (AUC) of 0.80, a sensitivity of 79% and a specificity of 76% (cut‐off point = 17). For the ability of the instruments to detect patients with mental disorders in general, the GHQ‐12 (AUC: 0.68) shows a similar overall accuracy to the HADS (AUC: 0.70). The screening performance of both scales for comorbid mental disorders is comparable. The HADS is a valid screening instrument for depressive and anxiety disorders in cancer care. The GHQ‐12 can be considered as an alternative to the HADS when diagnostic specifications are less detailed and the goal of screening procedures is to detect patients with single or multiple mental disorders in general. Limitations of conventional screening instruments are given through the differing methodological approaches of screening tests (dimensional approach) and diagnosis according to DSM‐IV (categorical approach). Copyright © 2001 Whurr Publishers Ltd.