The study measured the accuracy of the Italian version of the Mood Disorder Questionnaire (MDQ) as a screening instrument for bipolar disorders in a psychiatric setting.
Methods: 154 consecutive subjects attending the Division of Psychiatry of the University of Cagliari (Italy), were screened for bipolar disorders using the Italian translation of the MDQ, and diagnostically interviewed with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID) by physicians.
Results: On the basis of the SCID: 51 (33.1%) received a diagnosis of bipolar or schizoaffective bipolar type disorders, 63 (40.9%) were diagnosed as having at least one psychiatric disorder in Axis I (other than bipolar or schizoaffective bipolar type disorders), whilst 40 (25.9%) were unaffected by any type of psychiatric disorder. MDQ showed a good accuracy for bipolar or schizoaffective bipolar type disorders: the cut-off 4 had sensitivity 0.90 and specificity 0.58; the cut-off 5 had sensitivity 0.84 and specificity 0.70; and the cut-off 6 had sensitivity 0.76 and specificity 0.86. The accuracy for bipolar II disorders was sufficient but not excellent: the cut-off 4 had sensitivity 0.80 and specificity 0.45; the cut-off 5 had sensitivity 0.70 and specificity 0.55; and the cut-off 6 had sensitivity 0.55 and specificity 0.65.
Conclusion: Our results seem to indicate a good accuracy of MDQ, and confirm the results of recent surveys conducted in the USA. Moreover the instrument needs to be validated in other settings (e.g. in general practice).