Beck argued for a broad content, seeing depression “as a complex disorder involving affective, cognitive, motivational, and behavioral components.” (5, p187). He recorded attitudes, behaviors, and symptoms that were specific to clinically depressed patients and were consistent with psychiatric literature at the time. These were grouped into the 21 symptom categories that make up the BDI. Beck observed that as depression deepens, the number of symptoms increases, with a progression in the frequency and intensity of each (5, p188; 6, p154). Hence, the structure of the BDI includes graded levels of intensity of each symptom.