“…Accordingly, we focused not only on depression (Barnes et al, 2013; French et al, 2017; Hundt et al, 2013) but included different diagnoses, which also implied heterogeneity. Study limitations refer to the small accidental sample size, reactivity due to an awareness of being interviewed, self-assessment bias (Walfish, McAlister, O’Donnell, & Lambert, 2012), patient selection by therapists (which is why it remains unclear whether prototypical or especially cooperative patients were included), of therapies mainly in the early stages, and the restriction to a university treatment setting.…”