Screening for psychiatric disorders in patients with skin diseases: a performance study of the 12-item General Health Questionnaire.

Objective: Although psychiatric disorders are frequent among dermatological patients, no study has formally assessed the performance of any psychiatric screening questionnaire in dermatological practice. This study tested the ability of the 12-item General Health Questionnaire (GHQ-12) to identify psychiatric morbidity in dermatological patients.

Methods: A sample of 521 adult inpatients (81% of all eligible patients) completed the GHQ-12 and were administered the Structured Clinical Interview for DSM-IV Axis I disorders (SCID-I) by a trained mental health professional masked to GHQ-12 score.

Results: The Receiver Operating Characteristic (ROC) analysis showed that GHQ-12 possesses substantial discriminatory ability (area under the curve=0.70). The best balance between sensitivity (68%) and specificity (64%) was found at the GHQ-12 cutoff score of 3/4. This threshold gave a likelihood ratio for a positive or negative result of 1.90 and 0.50, respectively.

Conclusion: The performance of GHQ-12 was reasonably good for a self-administered questionnaire requiring only a few minutes to be completed and scored. Its routine use might increase recognition of psychiatric disorders in dermatological patients and contribute to improve patients' outcome.