Funding for this research was provided by:
Received: 24 March 2018
Accepted: 29 May 2018
First Online: 20 June 2018
Ethics approval and consent to participate
: The study protocol was approved by the local ethics committee (EKBB, trial registration number 37/09) on 02 April 2009. Participants were informed of the study objectives and gave their written informed consent prior to their inclusion.
: David Miedinger and Katrin Uehli were employed by Suva during the data collection and analysis phase of this study. Other authors declare that they have no competing interests.
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