Content validity of the Psychiatric Symptom Index, CES-Depression Scale, and State-Trait Anxiety Inventory from the perspective of DSM-IV

We compared the item content of three commonly used scales of psychiatric symptoms [the broad-band Psychiatric Symptom Index (Ilfeld) and two narrow-band scales, the Center for Epidemiologic Studies-Depression Scale (Radloff) and the State-Trait Anxiety Inventory (Spielberger)], with diagnostic criteria and criterion-based symptoms for Major Depressive Episode and Generalized Anxiety Disorder as they appeared in DSM-IV. The Psychiatric Symptom Index and the Center for Epidemiologic Studies-Depression Scale each measured 7 of 9 criterion-based symptoms of Major Depressive Episode. The Psychiatric Symptom Index and State-Trait Anxiety Inventory each measured 5 of 8 domains for Generalized Anxiety Disorder. The Psychiatric Symptom Index had comparable content validity to the narrow-band measures. All met a majority of DSM-IV criteria for depression and anxiety, supporting their applicability for current research.