OBJECTIVES: The Mood Disorder Questionnaire (MDQ) is a screening instrument for bipolar spectrum disorders. The MDQ is already validated in many different languages, but a validated Brazilian Portuguese version is not yet available.
METHODS: Patients from 2 psychiatric outpatient facilities diagnosed with BD type I and II (BDI and BDII) and major depression (MD) according to the mood module of the structured clinical interview for DSM-IV (SCID-CV). Also, a control group of healthy subjects (HS) was selected. The diagnostic interviews were used as the gold standard against which to investigate the performance of the MDQ. The MDQ was administered to 153 subjects, distributed among the four groups. We analyzed the test reliability and discriminative capacity of the MDQ for the detection of patients with BD.
RESULTS: Based on the SCID-CV: 51 (33,3%) subjects presented a bipolar spectrum disorder (type I, II, or not otherwise specified), 48 (32,4%) were diagnosed as having unipolar depressive disorder, whilst 54 (35,3%) were unaffected by any type of psychiatric disorder (had no psychiatric disorder according to SCID results). The sensitivity for bipolar disorder was 0.72 (bipolar I disorder 0.79, bipolar II disorder 0.58) with specificity 0.95.
CONCLUSIONS: The Brazilian Portuguese MDQ demonstrated adequate internal consistency (Cronbach alpha=0.87). The performance of the Brazilian Portuguese MDQ is comparable to the one reported in the original American study. In a psychiatric outpatient sample, the Brazilian Portuguese MDQ proves to be a feasible and reliable screening instrument.