A validation study of the Four-Dimensional Symptom Questionnaire (4DSQ) in insurance medicine

This study aimed to evaluate the criterion validity and the diagnostic accuracy of the Four-Dimensional Symptom Questionnaire (4DSQ) regarding the identification of depressive and anxiety disorders in an insurance medicine setting.

Our sample consisted of 230 individuals who applied for a work disability benefit due to mental health problems.

Depressive and anxiety disorders were assessed using the 4DSQ and the Composite International Diagnostic Interview (CIDI). Internal consistency was determined by calculating Cronbach's alpha values. Criterion validity was evaluated by regression techniques. A Receiver Operating Characteristic (ROC) analysis was performed to evaluate diagnostic accuracy.

Of the 230 participants 109 (47.4%) had a current DSM-IV depressive disorder and 146 (63.5%) an anxiety disorder. The 4DSQ scales showed an excellent internal consistency. The depression scale of the 4DSQ had specific sensitivity for major depressive disorder. The anxiety scale was also sensitive for the anxiety disorders. The area under the ROC curve (AUC) indicated good diagnostic accuracy of the 4DSQ for assessing depressive and/or anxiety disorders: AUC-value 0.81 for both depression and anxiety.

Although the 4DSQ shows good criterion validity and diagnostic accuracy with respect to depressive and anxiety disorders in applicants for a work disability benefit due to mental health problems, the feasibility of the 4DSQ as a screening measure for depressive and anxiety disorders is limited due to the high prevalence of depressive and anxiety disorders.