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Article History

Received: 10 July 2018

Accepted: 15 August 2018

First Online: 6 September 2018

Ethics approval and consent to participate

: Approval for this study was obtained together with a previously published randomized controlled trial (RCT; ISRCTN 71391952) from the ethics committee of the municipality of Vienna (EK 11–201-1111). All participants gave informed written consent.

: Not applicable.

: The authors declare that they have no competing interests.

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