Background: A major depressive episode diagnosed according to DSM-IV criteria can be accompanied by symptoms that DSM-IV does not include. These symptoms are sometimes classified as comorbidities. Our study assessed altered behavioral modes during a major depressive episode; ie, if 1 or more modes of behavior operated less or even not at all (“never”), or if the operation of others was more frequent or even constant (“always”). We hypothesize that these altered behavioral modes, especially the extreme positions “never” (hypomodes) and “always” (hypermodes) might correlate with depression scores and thus represent a typical symptom of depression.
Material/Methods: We used the 35-item Salzburg Subjective Behavioral Analysis (SSBA) questionnaire to measure altered behavioral modes in 63 depressed patients and 87 non-depressed controls. Depression was assessed using the Hamilton Depression Scale.
Results: In our test group (n=63) we found a total of 888 extreme positions. The mean number of extreme positions per patient was 11.15±5.173 (SD). Extreme positions were found in all 35 behavioral modes. The mean Hamilton score was 22.08±7.35 (SD). The association of the incidence of extreme positions and the Hamilton score in our test group was highly significant (Spearman’s Rho=0.41; p=.001). In the control group (n=87), only 11 persons were found to display extreme positions, with a total of only 25.
Conclusions: Although this study has several limitations, such as the small sample or the use of a questionnaire in the validation procedure, the significant correlation of extreme positions and the Hamilton score indicate that altered modes of behavior as detected with the SSBA might be typical symptoms in a major depressive episode.

Keywords: Depressive Disorder, Major - psychology, Behavior, Austria, young adult