Depression is a mood disorder marked by such symptoms as depressed mood, loss of pleasure in activities, sleep difficulties, appetite or weight changes and thoughts about suicide or death. To measure the severity of depression, mental health professionals and researchers often use tests. The Beck Depression Inventory is a common test to assess depression in adolescents and adults.
History
Aaron Beck, M.D., a psychiatrist and professor emeritus at the University of Pennsylvania, developed the Beck Depression Inventory (BDI), which was originally published in 1961. The BDI was revised in 1978 as the BDI-1A and again in 1996 as the BDI-II.
Test Items
The most recent version of the BDI, the BDI-II, has 21 items with four multiple-choice responses. Each item measures a specific symptom of depression. The assessed symptoms of depression include depressed mood, feeling hopeless, feelings of failure, loss of pleasure, feeling guilty, punishment, self-dislike, blaming self, suicidal thoughts, crying, agitation, loss of interest in activities, indecisiveness, feeling worthless, fatigue, sleeping difficulties, feeling irritable, appetite difficulties, decreased concentration, loss of energy and loss of sexual desire. The BDI-II takes about five to 10 minutes to complete.
Scoring
Each of the four multiple-choice responses is given a score from one to three. This score assesses the severity of the depressive symptom, with three being the most severe. The item scores are summed to yield a total score, which measures the severity of depression. Higher scores signify more severe depression. 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.
Validity
Validity is the degree to which a test accurately measures a concept. A validity assessment found the BDI-II to appropriately measure depression, as noted by Beck in the "Manual for the Beck Depression-II." The assessment of depression by the BDI-II is in agreement with other tests measuring depression, such as the Symptom Checklist-90 (SCL-90), according to a study by Steer in the April 1997 issue of "Psychological Reports."
Reliability
The BDI-II is a reliable test. Reliability is the consistency of a test, meaning that similar results repeatedly occur. Beck reported in the "Manual for the Beck Depression Inventory-II" that comparable test results occurred when people took the BDI-II on two separate occasions. Also, a statistical procedure found consistency between the BDI-II items , according to a study by Beck in the December 1996 issue of the "Journal of Personality Assessment."
References
- "Journal of Personality Assessment"; Comparison of Beck Depression Inventories -IA and --II in Psychiatric Outpatients; Aaron Beck, Robert Steer, Roberta Ball and William Ranieri; December 1996
- "Manual for the Beck Depression Inventory-II"; Aaron Beck, Robert Steer and Gregory Brown; The Psychological Corporation; 1996
- "Psychological Reports"; Further Evidence for the Construct Validity of the Beck Depression Inventory-II with Psychiatric Outpatients; Robert Steer, Roberta Ball, William Ranieri, and Aaron Beck; April 1997
