Duke Anxiety-Depression Scale (DUKE-AD)

Abstract

The Duke Anxiety-Depression Scale (DUKE-AD) is a highly concise, 7-item psychometric instrument developed primarily for the rapid screening and identification of symptoms associated with both anxiety and depression. Derived as a specialized subset from the larger 17-item Duke Health Profile (DUKE), the DUKE-AD is distinguished by its efficiency and low respondent burden. This makes it an invaluable tool for clinical application in non-psychiatric environments.

Specifically designed for use in primary care settings, the scale assesses a combination of affective, behavioral, and somatic indicators of psychological distress. The instrument employs two distinct Likert-type response formats to accurately capture the frequency and severity of reported symptoms, facilitating crucial early detection of common mental health disorders that might otherwise be overlooked in general medical practice.

Keywords

Anxiety, Depression, Screening, Primary care, Affective disorders, Duke Health Profile, DUKE-AD, Mental health, Psychometrics, Health status measurement, Somatic symptoms

Authors

G.R. Parkerson, Jr., W.E. Broadhead, C.K.J. Tse, S.H. Gehlbach, E.H. Wagner

Purpose

The core objective of the DUKE-AD is to function as an exceptionally efficient screening mechanism for identifying patients in primary care who exhibit symptoms of clinically significant anxiety or depression. The development of this instrument was motivated by the recognized necessity for a reliable, yet extremely brief, measure capable of detecting psychological distress within the severe time constraints typical of general medical practice.

By limiting the scale to just seven items, the DUKE-AD significantly minimizes respondent burden while maintaining sufficient psychometric properties—specifically sensitivity and specificity—to justify proceeding with a more extensive diagnostic evaluation when a positive screening result is obtained. Its successful application helps improve the recognition and subsequent referral or treatment for these highly prevalent mental health issues within non-specialized healthcare environments.

Construct

The DUKE-AD is constructed to measure general psychological distress primarily across the two highly correlated domains of anxiety and depression. The 7 items were carefully selected to represent a combination of self-reported affective states, observable behavioral characteristics, and common somatic symptoms that frequently co-occur with these mood disorders.

The instrument provides a rapid snapshot of distress through targeted items:

• Depressive Symptoms: These items focus on core elements of low mood, loss of motivation, and cognitive impairment, such as feeling depressed or sad, giving up easily, and difficulty concentrating.
• Anxiety Symptoms: These items capture generalized tension and discomfort, including self-reports of nervousness and an item related to social comfort (which is reverse-scored).
• Somatic and Functional Indicators: Physical manifestations, such as trouble sleeping and easily getting tired, are included as they are common physical complaints often masking underlying anxiety or depression in primary care settings.

Validity

The validity of the DUKE-AD is robustly supported by its direct lineage from the meticulously validated Duke Health Profile (DUKE). Validation studies have concentrated on the scale’s capacity to accurately differentiate between patients who meet clinical criteria for anxiety or depression and those who do not, typically utilizing established clinical interviews (such as those based on DSM criteria) as the criterion standard.

A primary statistical methodology employed to confirm the scale’s diagnostic utility is the use of Receiver operating characteristic (ROC) curves analysis. This method is critical for determining statistically optimal cutoff scores. These scores are set to maximize both the scale’s sensitivity (the rate of correctly identifying true positives) and its specificity (the rate of correctly identifying true negatives) when applied within diverse primary care patient populations, thereby confirming its practical efficacy as a screening tool.

Reliability

Although the DUKE-AD is an abbreviated measure, it demonstrates acceptable internal consistency suitable for a brief screening instrument. While specific coefficients like Cronbach’s alpha or test-retest coefficients are often reported in the extensive literature pertaining to the parent Duke Health Profile, the 7-item subset maintains adequate reliability necessary for initial clinical screening.

The scale’s reliability is inherently tied to the consistent performance and psychometric strength of the selected items. These items were rigorously chosen precisely because they consistently and reliably measure the targeted anxiety and depressive symptoms across various adult demographics, ensuring the resulting score is a dependable indicator of psychological distress.

Factor Analysis

The selection of the DUKE-AD items was heavily guided by prior factor analytic studies conducted on the full 17-item Duke Health Profile. These studies confirmed that the chosen items possess strong loadings onto the distinct, though highly correlated, underlying factors of anxiety and depression.

While the DUKE-AD is frequently utilized as a single, composite score reflecting overall psychological distress for rapid screening purposes, its theoretical foundation rests on these two separable dimensions. The reliance on rigorous factor analysis during development ensured that the scale maintains high construct purity despite its significant brevity, providing confidence that it measures the intended psychological domains.

Instrument

Test Type: Self-report screening instrument

Format: 7 items, utilizing two distinct Likert-type response scales to capture both frequency and intensity of symptoms.

Language Available: Primarily English; standardized translations are typically accessible through the broader documentation for the parent Duke Health Profile.

Population Group: Clinical and non-clinical adults; highly recommended for use in primary care environments.

Age Group: Adults (typically 18 years and older).

Population Details: Specifically suited for patients presenting for general medical care, where psychological distress may often be somaticized or obscured by physical complaints.

Test Methodology: Brief paper-and-pencil or digital administration, designed for minimal time investment (usually requiring less than 5 minutes for completion and scoring).

Keywords

Duke University Medical Center, Screening tool, Mental health assessment, Affective symptoms, Somatic complaints, Psychometrics, ROC analysis, Health status measurement

Authors

Author ORCID Identifier: Not specified in source materials.

Affiliation Email addresses: Correspondence should be directed to the Duke University Medical Center, Department of Community and Family Medicine, specifically for G.R. Parkerson, Jr. regarding licensing and usage.

Correspondence Address: Department of Community and Family Medicine, Duke University Medical Center, Durham, North Carolina.

Permissions & Fee and Test Year

The DUKE-AD falls under the umbrella of the Duke Health Measures suite, developed and maintained by the Duke University Medical Center. Information concerning usage permissions, applicable licensing fees, and access protocols are managed centrally by the Duke Center for Family Medicine.

The foundational research and initial validation studies leading to the specific anxiety-depression subscales were published prominently in the late 1980s and early 1990s (e.g., 1996, 1997). Official documentation and the instrument itself can be accessed via the Duke Health Measures website. The primary resource link is: https://cfm.duke.edu/research/duke-health-measures

Reference’s

• Parkerson, G.R., Jr., Gehlbach, S.H., Wagner, E.H., et al. (1981). The Duke-UNC Health Profile: an adult health status instrument for primary care. Med Care, 19:806–828.
• Parkerson, G.R., Jr., Broadhead, W.E., Tse, C.K.J. (1990). The Duke Health Profile: a 17-item measure of health and dysfunction. Med Care, 28(11):1056–1072.
• Parkerson, G.R Jr., Broadhead, W.E., Tse C-K.J. (1991). Development of the 17-item Duke Health Profile. Family Practice, 8(4); 396-401.
• Parkerson, G.R., Jr., Broadhead, W.E, Tse, C.K.J. (1991). Comparison of the Duke Health Profile and the MOS Short-Form in healthy young adults. Med Care, 29:679–683.
• Parkerson, G.R., Jr., Broadhead, W.E., Tse, C.K.J. (1992). Quality of life and functional health of primary care patients. J Clin Epidemiol, 45:1303–1313.
• Parkerson, G.R., Jr. (1994). User’s guide for the Duke Health Profile (DUKE). Durham, North Carolina: Duke University Medical Center.
• Parkerson, G.R., Jr., Broadhead, W.E., Tse, C.K. (1995). Health status and severity of illness as predictors of outcomes in primary care. Med Care, 33:53–66.
• Parkerson, G.R., Jr., Broadhead. W,E., Tse, C.K.J. (1996). Anxiety and depressive symptom identification using the Duke Health Profile. J Clin Epidemiol, 49(1):85–93.
• Parkerson, G.R., Jr., Broadhead. W,E. (1997). Screening for anxiety and depression in primary care with the Duke Anxiety-Depression Scale. Family Medicine, 29(3):177-181.
• Parkerson, G.R., Jr. (2002). Users guide for Duke health measures. Durham, N.C.: Department of Community and Family Medicine, Duke University Medical Center.
• McDowell, Ian. (2006). Measuring Health: A Guide to Rating Scales and Questionnaires, Third Edition. OXFORD UNIVERSITY PRESS.

Items of the Duke Anxiety-Depression Scale (DUKE-AD)

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

Responses: (2) Yes‚ describes me exactly; (1) Somewhat describes me; (0) No‚ doesn’t describe me at all

1. I give up too easily
2. I have difficulty concentrating
3. I am comfortable being around people*

During the past week: (Responses: (0) None; (1) Some; (2) A Lot)

How much trouble have you had with:

4. Sleeping
5. Getting tired easily
6. Feeling depressed or sad
7. Nervousness

Note on Scoring: Item 3 is reversed scored.