MethodsLiterature search timeframe: The references cited in the previous guidelines [1] are not repeated here, except for some relevant publications, and only the previous guidelines are cited instead. All publications published after the previous guidelines (i.e., from January 2004 to December 2014), have been considered for the first draft of this manuscript. Randomized controlled trials (RCTs), review articles, prospective studies and meta-analyses published in 2015 and 2016, during the revision process, have also been considered.Type of publications: Original papers, meta-analyses and reviews.
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