Major Depression Inventory (MDI)

The Major Depression Inventory (MDI) is a self-report questionnaire developed for the detection of depressive symptomatology and the assessment of depression severity. Created by the World Health Organization Collaborating Centre for Mental Health in Denmark, the MDI was designed to align with both the diagnostic criteria of the International Classification of Diseases, Tenth Revision (ICD-10) for depressive episodes, and those of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) for major depressive episodes. This alignment ensures the MDI's relevance and applicability across different clinical and research settings.

The MDI consists of 12 items, each addressing a core symptom of depression. Respondents are asked to evaluate how each symptom has affected them over the past two weeks, using a six-point scale ranging from “at no time” to “all the time.” This allows for a nuanced understanding of the individual’s emotional and functional state. The inventory is distinctive in its dual diagnostic capability; it can be scored to reflect the severity of depression as well as to establish a diagnostic threshold, which makes it a comprehensive tool for both screening and detailed assessment.

In practice, the MDI offers several advantages. It is quick and easy for patients to complete, usually requiring no more than five minutes. This ease of administration makes it particularly useful in both primary care and psychiatric settings, where time and resources may be limited. Additionally, the MDI's structure facilitates straightforward scoring and interpretation, enabling healthcare providers to make informed decisions about further diagnostic evaluations or treatment options.

The Major Depression Inventory serves as a practical tool in the identification and evaluation of depression. Its development was informed by significant advancements in psychiatric diagnostic criteria, ensuring its utility and relevance in contemporary mental health care. The MDI continues to be employed widely, contributing to the effective management and treatment of individuals experiencing major depressive episodes.

The following questions ask how you have been feeling over the last 2 weeks.

  All The Time Most Of The Time Slightly More Than Half The Time Slightly Less Than Half The Time Some Of The Time At No Time
1. Have you felt low in spirits or sad?
2. Have you lost interest in your daily activities?
3. Have you felt lacking in energy and strength?
4. Have you felt less self-confident?
5. Have you had a bad conscience or feelings of guilt?
6. Have you felt that life wasn’t worth living?
7. Have you had difficulty in concentrating?
8. Have you felt very restless?
9. Have you felt subdued or slowed down?
10. Have you had trouble sleeping at night?
11. Have you suffered from reduced appetite?
12. Have you suffered from increased appetite?
  1. P Bech, et al. The sensitivity and specificity of the Major Depression Inventory, using the Present State Examination as the index of diagnostic validity. 66 J Affect Disord 159-164. (2001).
  2. LR Olsen, et al. The internal and external validity of the Major Depression Inventory in measuring severity of depressive states. 33 Psychological Medicine 351-356. (2003).