Its development marked a shift among mental health professionals, who had until then, viewed depression from a psychodynamic perspective, instead of it being rooted in the patient's own thoughts.
The BDI was used as a model for the development of the Children's Depression Inventory (CDI), first published in 1979 by clinical psychologist Maria Kovacs.
[8][9] The internal consistency for the BDI-IA was good, with a Cronbach's alpha coefficient of around 0.85, meaning that the items on the inventory are highly correlated with each other.
In this respect, the BDI-II is positively correlated with the Hamilton Depression Rating Scale with a Pearson r of 0.71, showing good convergent validity.
The test was also shown to have a high one-week test–retest reliability (Pearson's r = 0.93), suggesting that it was not overly sensitive to day-to-day variations in mood.
[9] The development of the BDI was an important event in psychiatry and psychology; it represented a shift in health care professionals' view of depression from a Freudian, psychodynamic perspective, to one guided by the patient's own thoughts or "cognitions".
[3] It also established the principle that instead of attempting to develop a psychometric tool based on a possibly invalid theory, self-report questionnaires when analysed using techniques such as factor analysis can suggest theoretical constructs.
Because it is designed to reflect the depth of depression, it can monitor changes over time and provide an objective measure for judging improvement and the effectiveness or otherwise of treatment methods.
If a patient is asked to fill out the form in front of other people in a clinical environment, for instance, social expectations have been shown to elicit a different response compared to administration via a postal survey.
[19] Although designed as a rating scale device rather than a diagnostic tool, the BDI is sometimes used by health care providers to reach a quick diagnosis.