Improved bipolar screening with combined scales
medwireNews: Research findings suggest combining the Mood Disorder Questionnaire (MDQ) and Bipolar Spectrum Diagnostic Scale (BSDS) provides better diagnostic screening than using each in isolation.
"Simultaneous use of both instruments constitutes a complementary and optimal screening method because the MDQ is effective in screening for BD-I [bipolar disorder I], and the BSDS is effective in screening for bipolar spectrum disorders," say Boseok Cha (Gyeongsang National University Hospital, Korea) and co-authors.
A previous study found that combining the MDQ and BSDS resulted in higher sensitivity for BD, but combination cutoff scores, sensitivity, and specificity according to subtypes were not investigated.
The current research findings may assist BD diagnosis in patients treated for major depressive episodes, given that this patient population is often misdiagnosed in primary care settings, with research showing an average 10-year delay before a BD diagnosis is made.
The study, published in Comprehensive Psychiatry, involved the screening of 113 patients diagnosed with current major depressive episodes with the MDQ and BSDS. Patients had their initial diagnosis confirmed during a 1-year follow up.
A cutoff score of 6 on the MDQ or 10 on the BSDS were found to be optimal in the study, and the most accurate method of diagnosis was giving a positive diagnosis to patients who had a score on either tool that was at or above the cutoff.
Compared with using the MDQ and BSDS in isolation, combining the screening tools resulted in better sensitivity (0.741 and 0.731 vs 0.901, respectively) but less specificity (0.875 and 0.742 vs 0.688). Positive and negative predictive values were comparable.
The researchers note that the MDQ and BSDS can be completed in a short amount of time. "Using both measures simultaneously with patients with depression at outpatient psychiatric clinics should decrease the false-negative rate in BD screening," they say.
BD subtype-specific sensitivity was 1.000 (ie, perfect sensitivity) for BD-I and 0.877 for BD-II and BD-not otherwise specified (NOS), showing an improvement from 0.730 on the BSDS for BD-I and from 0.677 on the MDQ for BD-II and BD-NOS.
As shown in previous studies, the MDQ alone provided comparable sensitivity for BD-I relative to combined use with the BSDS, while the opposite was true for the BSDS, showing greater sensitivity for BD-II and BD-NOS.
"Simultaneous use of both instruments can provide a more effective method for determining whether a comprehensive and detailed clinical assessment for BD is needed," concludes the team.
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By Ingrid Grasmo, medwireNews Reporter