Correction to: Evaluating the structural reform of outpatient psychotherapy in Germany (ES-RiP trial) - a qualitative study of provider perspectives - Regina Poß-Doering; Martin Hegelow; Milena Borchers; Mechthild Hartmann; Johannes Kruse; Hanna Kampling; Gereon Heuft; Carsten Spitzer; Beate Wild; Joachim Szecsenyi; Hans-Christoph Friederich (BMC, 2021)