A multisample item response theory analysis of the Beck Depression Inventory-1A

The widespread employment of the Beck Depression Inventory-1A (BDI-1A) has spawned a number of practices: 1) The employment of an unweighted total sco re as a measure of depression; 2) Its use in populations other than that in which it was normed; and 3) The employment Of BDI-1A total scores in hypot hesis tests about population differences in mean depression. A sequential p rocedure based on item response theory was employed to assess the validity of these practices for the case of four populations: clinical depressives, mixed nondepressed psychiatric patients, and students from two different un iversities. The findings suggested that the first practice was not justifie d for any of these populations, that the BDI-1A was employable only with cl inical depressives and with one of the university populations, and that mea n comparisons were not allowable.