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Article History

Received: 9 April 2018

Accepted: 14 August 2018

First Online: 11 September 2018

Ethics approval and consent to participate

: This study has been approved by Geneva Research Ethics Committee, reference number 14–022. Each participant signed a written informed consent form.

: No identifiable material is published and therefore no consent to publish is required.

: All authors have completed the Unified Competing Interest form (available on request from the corresponding author) and declare no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years, as well as during this study, no other relationships or activities that could appear to have influenced the submitted work.

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