Validation of an Inventory for Measuring Depression.

The assessment and measurement of the mental state in patients suffering from a depressive illness is important both in clinical psychiatry and in research. Clinical assessment by an experienced psychiatrist, even when it is quantified on the basis of a rating scale (e.g. Hamilton's Rating Scale for Depression) has the disadvantage of being dependent on the skill of the rater and on his clinical bias. These drawbacks make it somewhat difficult to corn pare meaningfully results obtained in different investigations. We decided to explore the value of a self rating questionnaire which is completed by the patient. We selected the Inventory for Measur ing Depression, which was first validated on American patients (Beck et al., 1961) with satisfactory results, and we have been able to extend their observations to English patients. We have found this Inventory a satisfactory and reliable method of assessing depressive illness. It has the advantages of being very easily answered, of not requiring much time on the part of skilled personnel, and of being indepen dent of doctors' and nurses' bias. It is usually completed by the patient within ten minutes and can be scored in one or two minutes. It can be repeated by the patient without boredom or resentment at least once a week. In the great majority of occasions the test will effectively reflect the patient's depth of depression.