Ethics approval and consent to participate
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Further, this study was conducted in accordance with the current guidelines of good clinical practice, and in line with CONSORT guidelines for non-pharmacological studies. The ethics committee of the University Medicine Greifswald approved the study protocols of all included studies (study 1: number BB 64/07; study 2: number BB 002/15a; study 3: number BB 076/18). Written informed consent was obtained before inclusion of study participants.