Article History
Received: 22 February 2017
Accepted: 22 January 2018
First Online: 5 February 2018
Ethics approval and consent to participate
: An ethical approval for this study was not necessary as it was a meta-synthesis of published articles and did not involve data collection from participants.
: This study refers to already published articles and does not involve individual person’s data. Not applicable.
: The authors declare that they have no competing interests.
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