Article History
First Online: 4 April 2019
Compliance with ethical standards
:
: No funding was received for this study.
: S. Frey, T. Stargardt, U. Schneider and J. Schreyögg declare they have no conflict of interest relevant to this study.
: Informed consent was obtained from all individual participants included in the study.
: SF and US had complete access to the pseudonymised study dataset and were responsible for data collection. SF, TS, and JS designed the study. SF analysed the data and was responsible for statistical programming. SF and TS prepared the first draft, and JS and US revised the manuscript. All authors approved the final manuscript.
: The data that support the findings of this study are owned by the Techniker Krankenkasse (Bramfelder Straße 140, 22305 Hamburg, Germany) and so are not publicly available. To fulfil the legal requirements to access the data, researchers must obtain permission for a specific research question from the German Federal (Social) Insurance Office and conclude a contract with the sickness fund. The study must also be approved by the data protection officer, both at the sickness fund and the research institute, as well as the local ethics committee.