Beck Depression Inventory
The Beck Depression Inventory (BDI) is a series of questions developed to measure the intensity, severity, and depth of depression in patients with psychiatric diagnoses. Its long form is composed of 21 questions, each designed to assess a specific symptom common among people with depression. A shorter form is composed of seven questions and is designed for administration by primary care providers. Aaron T. Beck, a pioneer in cognitive therapy, first designed the BDI.
The BDI was originally developed to detect, assess, and monitor changes in depressive symptoms among people in a mental health care setting. It is also used to detect depressive symptoms in a primary care setting. The BDI usually takes between five and ten minutes to complete as part of a psychological or medical examination.
The BDI is designed for use by trained professionals. While it should be administered by a knowledgeable mental health professional who is trained in its use and interpretation, it is often self-administered.
The BDI was developed in 1961, adapted in 1969, and copyrighted in 1979. A second version of the inventory (BDI-II) was developed to reflect revisions in the Fourth Edition Text Revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR, a handbook that mental health professionals use to diagnose mental disorders).
The long form of the BDI is composed of 21 questions or items, each with four possible responses. Each response is assigned a score ranging from zero to three, indicating the severity of the symptom. A version designed for use by primary care providers (BDI-PC) is composed of seven self-reported items, each correlating to a symptom of major depressive disorder experienced over the preceding two weeks.
Individual questions of the BDI assess mood, pessimism, sense of failure, self-dissatisfaction, guilt, punishment, self-dislike, self-accusation, suicidal ideas, crying, irritability, social withdrawal, body image, work difficulties, insomnia, fatigue, appetite, weight loss, bodily preoccupation, and loss of libido. Items 1 to 13 assess symptoms that are psychological in nature, while items 14 to 21 assess more physical symptoms.
The sum of all BDI item scores indicates the severity of depression. The test is scored differently for the general population and for individuals who have been clinically diagnosed with depression. For the general population, a score of 21 or over represents depression. For people who have been clinically diagnosed, scores from 0 to 9 represent minimal depressive symptoms, scores of 10 to 16 indicate mild depression, scores of 17 to 29 indicate moderate depression, and scores of 30 to 63 indicate severe depression. The BDI can distinguish between different subtypes of depressive disorders, such as major depression and dysthymia (a less severe form of depression).
The BDI has been extensively tested for content validity, concurrent validity, and construct validity. The BDI has content validity (the extent to which items of a test are representative of that which is to be measured) because it was constructed from a consensus among clinicians about depressive symptoms displayed by psychiatric patients. Concurrent validity is a measure of the extent to which a test concurs with already existing standards; at least 35 studies have shown concurrent validity between the BDI and such measures of depression as the Hamilton Depression Scale and the Minnesota
Factor analysis, a statistical method used to determine underlying relationships between variables, has also supported the validity of the BDI. The BDI can be interpreted as one syndrome (depression) composed of three factors: negative attitudes toward self, performance impairment, and somatic (bodily) disturbance.
The BDI has also been extensively tested for reliability, following established standards for psychological tests published in 1985. Internal consistency has been successfully estimated by over 25 studies in many populations. The BDI has been shown to be valid and reliable, with results corresponding to clinician ratings of depression in more than 90% of all cases.
Higher BDI scores have been shown in a few studies to be inversely related to educational attainment; the BDI, however, does not consistently correlate with sex, race, or age.
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th edition, text revised. Washington, D.C.: American Psychiatric Association, 2000.
Beck, A. T., A. J. Rush, B. F. Shaw, and D. Emery. Cognitive therapy of depression. New York: Guilford Press, 1979.
Beck, A. T., and R. A. Steer. "Internal consistencies of the original and revised Beck Depression Inventory." Journal of Clinical Psychology 40 (1984): 1365-1367.
Beck, A. T., R. A. Steer, and G. M. Garbin. "Psychometric properties of the Beck Depression Inventory: Twenty-five years of evaluation." Clinical Psychology Review, 8 (1988): 77-100.
Beck, A. T., D. Guthy, R. A. Steer, and R. Ball. "Internal consistencies of the original and revised Beck Depression Inventory." Journal of Clinical Psychology, 40 (1984): 1365-1367.
American Psychiatric Association. 1400 K Street NW, Washington D.C. 20005. <http://www.psych.org>.
The Center for Mental Health Services Knowledge Exchange Network (KEN). U.S. Department of Health and Human Services. (800) 789-2647. <http://www.mentalhealth.org>.
National Alliance for the Mentally Ill (NAMI). Colonial Place 3, 2107 Wilson Blvd, Suite 300, Arlington VA, 22201-3042. (703) 524-7600 or (800) 950-6264. <http://www. nami.org>.
National Depressive and Manic Depressive Association (NDMDA). 730 N. Franklin St, Suite 501, Chicago IL 60601-3526. (314) 642-0049 or (800) 826-3632. <http://www.ndmda.org>.
National Institute of Mental Health. 6001 Executive Boulevard, Rm. 8184, MSC 9663, Bethesda, MD 20892-9663. (301) 443-4513. <http://www.nimh.nih.gov>.
Substance Abuse and Mental Health Services Administration (SAMHSA). Center for Mental Health Services (CMHS), Department of Health and Human Services, 5600 Fishers Lane, Rockville MD 20857. <http://www.samhsa.org>.
Michael Polgar, Ph.D.