What is the role of the Mood Disorder Questionnaire (MDQ) in diagnosing and managing bipolar disorder?

Mood Disorder Questionnaire (MDQ): Overview and Clinical Utility

What is the MDQ?

The Mood Disorder Questionnaire (MDQ) is a self-report screening tool designed to identify bipolar spectrum disorders, but its clinical utility is limited by inadequate sensitivity (particularly for bipolar II disorder) and low positive predictive value, making routine clinical use problematic without careful interpretation. 1, 2, 3

The MDQ consists of 13 yes/no questions about manic/hypomanic symptoms, plus supplementary questions about symptom clustering and functional impairment 1. The original scoring criteria require:

• 7 or more endorsed symptoms
• Several symptoms occurring during the same time period
• Moderate to severe functional impairment 1, 2

Performance Characteristics

In Psychiatric Outpatient Settings

• Sensitivity: 63.5% when using standard scoring criteria, meaning it misses over one-third of bipolar cases 2
• Specificity: 84.8%, indicating reasonable ability to rule out bipolar disorder 2
• Positive predictive value: only 33.7%, meaning most positive screens are false positives 2
• Sensitivity improves to 75% if the impairment criterion is dropped, but positive predictive value drops to 29.8% 2

Differential Performance by Bipolar Subtype

The MDQ performs significantly better for bipolar I disorder (sensitivity 66.3%) compared to bipolar II disorder (sensitivity 38.6%), making it inadequate for detecting hypomania. 3 In UK samples, bipolar II sensitivity was only 67% with standard scoring but improved to 88% when using a threshold of 9+ symptoms without supplementary questions 1.

In General Population vs. Clinical Settings

Studies in general populations show much lower sensitivity and positive predictive value compared to psychiatric settings, with higher specificity and negative predictive value 3. This means the MDQ is better at ruling out bipolar disorder in community samples than identifying it.

Recent Research Findings

A 2023 genetic study raises fundamental questions about what the MDQ actually measures, suggesting it may capture general distress or psychopathology rather than specific manic symptoms. 4 Key findings include:

• The MDQ showed low positive predictive value (0.29) for self-reported bipolar disorder 4
• Neither concurrent nor lifetime manic symptoms measured by the MDQ were genetically correlated with bipolar disorder 4
• The MDQ showed stronger genetic correlations with PTSD (rg = 1.0), ADHD (rg = 0.69), insomnia (rg = 0.55), and major depression (rg = 0.42) than with bipolar disorder 4

Clinical Recommendations

When to Consider Using the MDQ

The American Academy of Child and Adolescent Psychiatry recommends screening for bipolar disorder by asking about distinct, spontaneous periods of mood changes associated with sleep disturbances and psychomotor activation, rather than relying solely on questionnaires. 5, 6

Specific screening questions should focus on:

• Distinct episodes of elevated, expansive, or euphoric mood clearly different from baseline 5
• Decreased need for sleep (not just insomnia) 5, 6
• Marked increases in goal-directed activity or psychomotor agitation 5
• Episodic rather than chronic patterns 5

Critical Limitations and Pitfalls

Avoid relying solely on the MDQ or similar checklists to identify bipolar disorder; symptoms must be assessed in context of family history, longitudinal course, and functional impairment. 6, 7 Common pitfalls include:

• Misinterpreting chronic irritability as mania: The MDQ cannot distinguish between episodic manic irritability and chronic irritability from conditions like DMDD, ADHD, or PTSD 5
• Overdiagnosis risk: The low positive predictive value means most positive screens require comprehensive diagnostic interviews using DSM criteria 6, 3
• Missing bipolar II disorder: Standard MDQ scoring has particularly poor sensitivity for hypomania 1, 3

Proper Diagnostic Approach

All positive MDQ screens must trigger full diagnostic interviews using standard DSM criteria, including assessment of episode duration (≥4 days for hypomania, ≥7 days for mania), functional impairment, and differentiation from other psychiatric conditions. 5, 6

The diagnostic assessment should include:

• Longitudinal life chart mapping symptom patterns, episode duration, and treatment responses 5, 6
• Collateral information from family members who can describe behavioral changes objectively 5
• Family psychiatric history, particularly of mood disorders 8, 6
• Substance use history with toxicology screening to rule out substance-induced mood disorder 5
• Medical evaluation including thyroid function, CBC, and metabolic panel 5
• Assessment of suicidality, given high suicide attempt rates in bipolar disorder 5, 7

Bottom Line on Clinical Use

Based on current evidence, routine clinical use of the MDQ cannot be recommended because studies have not demonstrated that screening improves detection without causing harm through overdiagnosis and inappropriate treatment. 3 The 2011 Harvard Review of Psychiatry concluded that the absence of studies examining both benefits and costs of MDQ screening precludes recommending its routine use 3.

If used at all, the MDQ should be considered only as an initial prompt for further evaluation in psychiatric settings, never as a diagnostic tool, and clinicians must recognize its poor performance for bipolar II disorder and potential to measure general psychopathology rather than specific manic symptoms. 1, 3, 4