Explicating the structure and relations of the Mood Disorder Questionnaire: Implications for screening for bipolar and related disorders.

BACKGROUND

The Mood Disorder Questionnaire (MDQ; Hirschfeld et al., 2000) is a widely used screening measure in bipolar disorder research. Although this measure assesses a heterogeneous range of content, only limited prior research utilizing relatively small sample sizes has examined its factor structure.

METHODS

The MDQ's structure was examined in 700 participants reporting current psychiatric treatment. We extended prior structural work on the MDQ by explicating relations between factors and a wide range of psychopathology and personality measures.

RESULTS

The MDQ items were best captured by a two-factor structure consisting of dimensions labeled Positive Activation and Negative Activation. These two factors showed very different patterns of associations with personality, other psychopathology, and ratings of significant impairment, the last of which is a requirement for a positive MDQ screen using traditional scoring methods.

LIMITATIONS

Our study did not include clinician or informant ratings of bipolar disorder, preventing us from examining associations with such scores.

CONCLUSIONS

Our findings indicate that although the MDQ items cohere to define a total score, their structure is best modeled by meaningful Positive Activation and Negative Activation factors. Researchers and clinicians should be aware of these distinct sets of MDQ content, as high scorers on Positive Activation are less likely to identify past symptoms as problematic and show distinct clinical profiles from high scorers on Negative Activation.