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Article History

Received: 17 October 2019

Accepted: 3 June 2020

First Online: 18 June 2020

Ethics approval and consent to participate

: None sought as this was a systematic review of published studies.

: Not applicable as the paper does not contain any individual person’s data.

: The authors declare that they have no conflict of interest. The authors would like to highlight that they included a paper they wrote in this review.