Ethical considerations
The study was approved by the research council
affiliated with a regional university. The council reviewed
the study and corroborated its ethical considerations. We
explained the aim, advantages and disadvantages of the
study for the patients. They were completely free to
whether participate in, decline participation or withdraw
from the study at any time throughout the study. The
patients were assured of the confidentiality of their
personal data. Subsequently, they provided the written
informed consent form.