“…In empirical research, a close association between therapist adherence and competence was found (Barber, Triffelman, & Marmer, ), which conforms with the notion that adherence is a precondition for competence (Waltz et al ., ). Furthermore, both theoretical reflections and empirical research suggest that therapist competence is a precondition for a good therapeutic alliance (Barber, Crits‐Christoph, & Luborsky, ; Despland et al ., ) and that a good therapeutic alliance is in turn the basis for a positive adherence–outcome relationship (Barber et al ., ; McLeod, Southam‐Gerow, Tully, Rodríguez, & Smith, ). Accordingly, previous research considered linear and curvilinear relationships.…”