Received: 8 November 2017
Accepted: 11 June 2019
First Online: 15 June 2019
Ethics approval and consent to participate
: Not applicable as the analysis is based on secondary data. However, DEGS1 was approved by the Charité-Universitätsmedizin Berlin ethics committee and participants provided written informed consent prior to the interview and examination [CitationRef removed–CitationRef removed].
: Not applicable.
: The authors declare that they have no competing interests.