Influence of established and subjectively perceived as well as evaluated individual characteristics on the utilization of mental health services among individuals with depressive disorders: protocol of a longitudinal study examining how to supplement the "behavioral model of health services use" and on need-congruent use of mental health services.

The study intends to contribute to the theoretical foundation of health services research and to specify the characteristics described in the ABM. Thus, after completion of the study, a further sophisticated and empirically tested model will be available to explain mental health services. The identified modifiable influencing factors are relevant for the development of strategies to increase mental health service use in line with the objective and subjective needs of individuals with depression.