Treatment selection and treatment initialization in guideline-based stepped and collaborative care for depression

In order to optimize patient allocation, guidelines recommend stepped and collaborative care models (SCM) including low-intensity treatments. The aim of this study is to investigate the implementation of guideline-adherent treatments in a SCM for depression in routine care. We analyzed care provider documentation data of n = 569 patients treated within a SCM. Rates of guideline-adherent treatment selections and initializations as well as accordance between selected and initialized treatment were evaluated for patients with mild, moderate and severe depression. Guideline-adherent treatment selection and initialization was highest for mild depression (91% resp. 85%). For moderate depression, guideline-adherent treatments were selected in 68% and applied in 54% of cases. Guideline adherence was lowest for severe depression (59% resp. 19%). In a multiple mixed logistic regression model a significant interaction between guideline adherence in treatment selection/initialization and severity degree was found. The differences between treatment selection and initialization were significant for moderate (OR: 1.8 [95% CI: 1.30 to 2.59; p = 0.0006]) and severe depression (OR: 6.9; [95% CI: 4.24 to 11.25; p < .0001] but not for mild depression (OR = 1.8, [95%-CI: 0.68 to 4.56; p = 0.2426]). Accordance between selected and initialized treatment was highest for mild and lowest for severe depression. We conclude that SCMs potentially improve care for mild depression and guideline adherence of treatment selections. Guideline adherence of treatment initialization and accordance between treatment selection and initialization varies with depression severity. Deficits in treating severe depression adequately may be more a problem of failed treatment initializations than of inadequate treatment selections.