The beck inventory depression ii is the most widely used instrument for assessing depression symptoms. This 21-item self-administered questionnaire asks respondents to recall how they have felt, based on their own experience over the past two weeks including today. Scores are obtained by summing the ratings on each of the items, and a BDI total of 13 or less indicates minimal depression; scores of 14 to 19 indicate mild depression; and a BDI score of 20 or more indicates moderate to severe depression. The BDI was developed in 1961 by Aaron T. Beck, and has been revised several times (e.g., as BDI-IA in 1978 and BDI-II in 1996).
The BDI is a highly sensitive measure of depression beck inventory depression ii with a sensitivity of up to 100%, meaning that it detects all cases of major depressive disorder when the cut-off score is used. Despite its high sensitivity, the BDI can miss some cases of depression. This occurs because some of the questions ask about subjective somatic symptoms, which overlap with true depression-related somatic complaints. The BDI is also susceptible to response bias, because respondents who are very ill may rate their feelings more negatively than those in better health. The BDI can be shortened to a 13-item version, the BDI-FastScreen for Medical Patients (BDI-FS), which has been found to have good validity and sensitivity in medical settings.
It is important for clinicians to understand the limitations of the BDI, and to consider how these factors affect its performance in specific clinical situations. A sensitivity of 100% is desirable in medical settings, but it may not be practical. A higher cut-off point would be necessary to avoid the false-negative results associated with using a very low sensitivity, and a greater specificity might be needed to detect depression in patients who have more subjective somatic symptoms.
In addition to its usefulness in screening for depression, the BDI has been found to be a reliable indicator of the severity of symptoms and the presence of suicidal thoughts, a significant risk factor for suicide. The BDI-FS is a valid and sensitive tool for measuring depression in medical settings, and it can be used to evaluate the effectiveness of treatment programs.
Further research is warranted to compare the BDI-FS with other measures of depression, such as the Patient Health Questionnaire and the Hamilton Anxiety Rating Scale, in medical settings. Ideally, any depression measurement tool used in medical settings should be user-friendly and easy to administer, with clear instructions and a brief format. It should be able to assess depression symptoms from the patients’ perspective, and should be easy to interpret for the clinician. In addition, it should be able to identify depressed patients in the context of somatic complaints and other diagnostic criteria, such as a diagnosis of mood disorders or chronic pain. Finally, the measure should be cost-effective, and preferably copyright-free, so that it can be easily used by healthcare professionals in their daily practice.